PROFESSIONS AND TRADES – HEALTH CARE PROFESSIONALS – MEDICAL
PRACTITIONERS – LIABILITY IN TORT – DUTY TO WARN
OF RISKS –
where the plaintiff patient had a mechanical heart valve – where as a
Source
Original judgment source is linked above.
Catchwords
PROFESSIONS AND TRADES – HEALTH CARE PROFESSIONALS – MEDICALPRACTITIONERS – LIABILITY IN TORT – DUTY TO WARNOF RISKS –where the plaintiff patient had a mechanical heart valve – where as aconsequence of this the plaintiff hadto take anti-coagulant medication,Warfarin, for the rest of her life – where the levels of Warfarin in theblood needed tobe monitored to ensure they remained within an appropriate range– where there were serious risks of blood clots and strokewhen the levelsof Warfarin dropped below the target range – where there were seriousrisks of bleeding when the levels ofWarfarin were above the target range– where the defendant firm of specialist medical pathologists monitoredthe plaintiff- where the plaintiff had five blood tests within 12 days showingher Warfarin level was below the target range – where thedefendantadvised the plaintiff and her general practitioner that they would no longer be
monitoring her Warfarin levels –
where the defendant did not tell the
plaintiff, her general practitioner or her cardiologist that her Warfarin levels
were below
the target range – where the plaintiff suffered a stroke
– whether the defendant breached its duty of care to the plaintiff
[1] The plaintiff, who was born on 28 May 1956, suffered from mitral incompetence, i.e. a leaking valve between the left atrium and left ventricle in her heart. On
[2]
11 July 2001, she underwent surgery for this condition by a procedure known as a mitral valve replacement, in which an artificial mechanical valve was inserted in her heart.
[3]
[2] A consequence of the insertion of this mechanical valve was that it became necessary for the plaintiff to take anti-coagulant medication for the rest of her life to assist in preventing the formation of clots around the valve or in the heart. Her cardiac surgeon prescribed the anti-coagulant, Warfarin.
[4]
[3] The levels of Warfarin in a patient's blood need to be monitored in order to ascertain whether they are within an appropriate therapeutic range and the dosages of Warfarin need to be adjusted in order to keep the Warfarin level within that range.
[5]
[4] The defendant is a firm of specialist medical pathologists. One of the services it has offered since 1999 is the Warfarin Care Service ("WCS"). The WCS takes samples of patients' blood and analyses them for the current Warfarin level. The patient is then advised by the WCS as to the dosage of Warfarin which he or she is to take until the next test and is also told when the next test is to be.
[6]
[5] In the period from 13-25 February 2002, the plaintiff had five blood tests with the WCS, each of which showed that her Warfarin level was "sub-therapeutic", i.e. below the target range of anti-coagulation. This meant that the plaintiff was at an increased risk of developing clots.
[7]
[6] On 27 February 2002, the defendant advised the plaintiff and her general practitioner, Dr Powell, that the defendant would no longer be monitoring the plaintiff's Warfarin levels and that she was, in effect, removed from the WCS. (The reasons for the defendant taking that step are no longer in issue on the pleadings.)
[8]
[7] On 28 February 2002, Dr Powell saw the plaintiff, and referred her to the Warfarin monitoring service run by another firm of pathologists, Queensland Medical Laboratories ("QML").
[9]
[8] On 1 March 2002, the plaintiff suffered a stroke (described as a "large right middle cerebral artery territory embolic infarction"), which was caused by an embolism, i.e. a blood clot.
[10]
[9] The plaintiff has been left significantly disabled by this stroke. She says that the stroke, and its consequences, were caused by the defendant's negligence or by breach of the terms implied in the defendant's retainer that it would exercise reasonable care and skill and claims damages from the defendant.[1]
[11]
[10] In order to make sense of what follows, it is necessary to go into some more detail about Warfarin and Warfarin testing.
[12]
[11] Warfarin is an anti-coagulant, i.e. it interferes with the clotting properties of blood. It is taken daily in tablet form. There are varying strengths of tablet to enable a patient to adjust dosage up and down, as they are advised to do so. Warfarin has been used as an anti-coagulant for many years. From the early 1990's, it was prescribed with increasing frequency as part of the treatment for patients suffering from the cardiac condition known as "atrial fibrillation".
[13]
[12] Warfarin levels in blood are monitored by a blood test which yields a number known as the "INR" (International Normalised Ratio). This is a standardised measure of the prothrombin level in blood. In lay terms, the INR provides a relative indication of the time it takes for a patient's blood to clot. In a person not taking Warfarin, the INR is 1. If a person is taking Warfarin, its anti-coagulant properties cause the blood to take longer to clot. If the particular patient's blood takes twice as long to clot, then they will have an INR of 2. Similarly, an INR of 7 indicates that the patient's blood will take seven times as long to clot.
[14]
[13] Target ranges are set by the referring physicians for the INR sought to be maintained for particular patients. It was not in issue in the present case that the INR target range set by the cardiac surgeon for this plaintiff was 3.0 - 4.0.
[15]
[14] Increased risks emerge for a patient if their INR drops below or exceeds the target range. If the INR drops to levels below the target range, the risk of the patient developing clots (including thromboembolisms) increases. If the INR exceeds the target range, the risk of the patient suffering from bleeding (including into the brain or spine) increases.
[16]
[15] As noted, the defendant set up the WCS in 1999. As at 2001-2002, the WCS was managing about 5,000 patients who were taking Warfarin. It was staffed by a clinical nurse manager, clinical staff, scientists and doctors.
[17]
[16] When the plaintiff was initially referred to the WCS, she was visited at home by a representative of the defendant and provided with a folder of documents.[2] The plaintiff gave evidence that she read and understood the documents that had been provided to her. One of the documents in this kit was an information sheet, which provided the following description of the testing process:
[18]
"Your doctor will give you a request form to have a blood test called a 'Prothrombin Time' (PT) test. Under the current Medicare schedule this request form is valid for the period defined by your doctor up to a maximum of six months. You may go to any of our collection centres for this test. A list of collection centres is provided for your information. Our laboratory network covers an extensive area north, south and west of Brisbane. If you are physically unable to get to a collection centre through illness or disability, we can arrange a home visit service.
[19]
At each visit, before the blood is collected, we will ask you to fill out a simple form to record any changes that may have occurred since your last test. To help us provide you with the best possible care, we need to know of any illnesses such as diarrhoea or vomiting, planned procedures (such as dental extractions or surgery), or changes to medication (the list of medications that interact with Warfarin is extensive).
[20]
Also, please inform us of any unexplained bruising, nose bleeds, if you have heavy bleeding from your gums after brushing, prolonged bleeding from small cuts, urine that is dark brown or contains blood, bowel movements that contain blood or appear black, or any other information that you think may be relevant.
[21]
You do not need to fast prior to collection unless you have been instructed to fast for other tests to be collected at the same time as your PT. If for some reason you have not taken your Warfarin as prescribed, remember to mention this to our staff. We will then take this into account when looking at the results of your test and ensure that your dose schedule will not be changed unnecessarily.
[22]
After your blood is collected, it is sent to the laboratory for testing. A scientist at the laboratory will refer your results to one of our highly trained pathologists. The pathologist will adjust your Warfarin dose as required (based on this day's results, your previous test results and doses, your medical condition for which you are on Warfarin, and any other relevant information that you gave us when you filled out the form mentioned above). You can access your dosage instructions after 4pm on the day of your test allowing 5 hours for your specimen to be processed."
[23]
[17] This information sheet, and other forms in the information kit, also emphasised:
[24]
(a) The importance of the patient maintaining a steady diet and avoiding large variations;
[25]
(b) The advisability of taking the Warfarin regularly once a day and at about the same time each day;
[26]
(c) The necessity to check with the prescribing practitioner or the defendant's clinical nurse manager before taking herbal preparations and other medication;
[27]
(d) The necessity (highlighted in the passage quoted above) for the patient to report illnesses, medication taken and any unexplained bruising or bleeding.
[28]
[18] In respect of each sample of blood taken from the patient, the blood would be tested for its INR, and the results referred to one of the defendant's haematologists for that specialist to review the result and fix the dosage to be advised to the patient.
[29]
Dr Rowbotham, the defendant's haematologist assessed the plaintiff's results in late February 2002, described the information which was then available to the defendant's haematologists as follows:
[30]
"How is the information from a pathology test produced for the haematologist or how was it produced in 2001, 2002?-- We had a specific database designed for the Warfarin dosing program and on that screen the patient's name, date of birth, the referring doctor, the indication for Warfarin therapy, the medical history, the current list of medications would all be at the top of the screen, the target range and any other information which was relevant to Warfarin treatment. There then would be 16 results on the screen at that time of INRs and doses for us to look at and by scrolling back you could get back right to the start of a patient's Warfarin therapy. So you would see the INR result of the day, you would know the previous result and whether or not it had been in range and you would know the interval between the tests and you would also be able to see whether or not the patient had supplied any information on the patient information form which they filled out every time they presented for a blood test."
[31]
[19] Clinical comments relevant to these entries were also accessed on this screen. These clinical comments included all information which the patient provided in respect of matters such as bruising or bleeding, other medication and other illnesses from which they were suffering. On some 35 occasions between 18 July 2001 and 25 February 2002, the WCS tested the plaintiff's blood to ascertain the INR and then advised her of the doses of Warfarin she was to take until her next test. For present purposes, it is sufficient to set out a table containing the test results and instructions given for December 2001 and January and February 2002. (This table also converts the dosing instruction into the average daily dose administered in accordance with the dosing instructions given from time to time and the dates on which the plaintiff was instructed to return for her next test.)
[32]
[20] A further test of the plaintiff's INR was available on 28 February 2002. Her INR at that time was 1.70, and she was advised of that by her GP, Dr Powell.
[33]
[21] The plaintiff described the circumstances under which she was referred to the defendant and receiving the information kit. She read that material and clearly understood what was required of her. Her evidence was as follows:
[34]
"What do you understand was required of you?-- That I needed to take the medication every day as directed by S & N in terms of dosage; I had to take it at the same time every day; I had to be careful about other medication, that I could only take medications prescribed by my doctor, I couldn't use over-the-counter medicines or herbal medicines or anything like that; that I needed to watch my intake, dietary intake of vitamin K; that I couldn't have excess alcohol; and that I needed to let S & N know of any changes in my medical circumstances that might affect the Warfarin."
[35]
[22] She was provided with a number of "blue books" in which she was to record the dates of her testing, the dosage instructions given to her and the dates of her next appointment. On a few occasions, the plaintiff was advised of the INR which a particular test had revealed. The plaintiff has lost one of her blue books, but nothing really turns on that. The plaintiff was required to phone the defendant after she had had each blood test done in order to receive her dosage instructions and next appointment date.
[36]
[23] The plaintiff said that she understood that she needed to advise the defendant about such things as taking any new medications, being sick, having excessive bleeding or bruising or any other abnormal signs to do with blood. She said that she advised the defendant of these matters as and when they occurred by filling out a form at the clinic she attended to have blood taken.
[37]
[24] It was not in issue before me that the plaintiff's INR readings between
[38]
13 February 2002 and 25 February 2002 were "sub-therapeutic". The plaintiff said that she was never advised of the sub-therapeutic readings by the defendant. She recounted a previous occasion when, having phoned for her results, the WCS representative had said that her INR had changed and asked questions about matters such as other medication, alcohol consumption, changes to her diet and so on. She said that none of those applied to her at that time. The person that she spoke to about this matter was "just somebody who worked on the results line and gave information to patients".
[39]
[25] The plaintiff said that she had no idea that her INR levels were sub-therapeutic between 13 and 25 February 2002. She described understanding the effect of sub-therapeutic INR readings as being "that clots could form on my heart valve and my understanding was as long as the INR was within the target range that risk was minimised". She said that she might not have had a full understanding of the implications of a prolonged sub-therapeutic INR, but she would have understood it if someone had explained it to her clearly.
[40]
[26] The plaintiff said that if, at any time during this period in late February 2002, a representative of the defendant had recommended to her that she should consult her general practitioner or cardiologist about her sub-therapeutic INR levels, she would have asked them "to elaborate a little bit, explain to me why I needed to do that, what the risks were to me and I would have gone and seen my GP or my cardiologist straight away". She also said that she would have then followed any recommendations given to her by her GP or cardiologist.
[41]
[27] The plaintiff saw her GP on 23 February 2002 to discuss weight loss. She had become significantly overweight and said that she knew that, because of the Warfarin, she would have to be careful about making any adjustments to her diet. She did not recall having any particular discussion with her doctor about the Warfarin therapy or INR. The plaintiff's GP referred her to a dietician, with specific instructions that they were to help her with weight loss but keeping the Warfarin in mind.
[42]
[28] On 27 February 2002, while the plaintiff was at work, she was notified that someone from the defendant had attempted to contact her. She returned the call, and spoke with one of the defendant's representatives (she thought it was the defendant's clinical nurse manager). The plaintiff had not spoken with this representative before. She said that the defendant's representative told her "I'm sorry we're not able to manage your Warfarin any more", and told her that she needed to go and see her GP. The plaintiff asked why, and the representative apologised, said that she could not tell her, and said that the plaintiff would have to ask her doctor. The plaintiff said this was the extent of the conversation and that she was "really shocked actually" because she had no idea of what was going on. She called her husband and then telephoned her doctor's surgery for the earliest possible appointment. That was on the following day, 28 February 2002.
[43]
[29] She attended on Dr Powell on 28 February 2002, and was referred to the other Warfarin service provider, QML. She recalled that Dr Powell made a small increase in the dosage of Warfarin. The arrangement was that the plaintiff was supposed to go back and see him after having her blood test with QML, and that if the INR was still below the requisite level Dr Powell was thinking about referring her to a haematologist.
[44]
[30] The plaintiff had the stroke on the following day.
[45]
[31] Under cross-examination, the plaintiff confirmed that she knew at the time that a low INR (i.e. a sub-therapeutic INR) posed a risk of her suffering a thrombotic stroke, while one of the risks associated with a high INR (i.e. above therapeutic range) was the risk of uncontrolled bleeding.
[46]
[32] She was then cross-examined at some length on her attendances on the defendant, her communications with the defendant and her knowledge on a few occasions of her INR. An attempt was made in cross-examination to link her knowledge of changing dosages with a pattern of changing INR's. The plaintiff, however, quite credibly said that she was not really analysing the dosages, but was following instructions given to her by the defendant.
[47]
[33] She was cross-examined on her attendance on Dr Powell on 23 February 2002. It was suggested to her that she also discussed on that occasion with Dr Powell the fact that her INR's had been unstable, but she said, "I don't remember that conversation". She conceded that it was possible that she had been discussing stress at work with him. She referred to having a discussion with him (which she initially thought was after she was discharged from the defendant's program) in which
[48]
Dr Powell told her that her INR's were erratic and he asked her if there was any reason for this, to which she responded that the only thing she could think of was stress. She conceded it was possible that this conversation occurred with Dr Powell on 23 February 2002.
[49]
[34] She was asked about bruising that she had reported to the WCS on 3 January 2002, describing it as bruising on her legs. She knew that it was a matter of significance, and she reported it to the defendant, as she had been instructed to do.
[50]
[35] She was then cross-examined on her attendance on Dr Powell after having been discharged from the defendant's program. She confirmed that in her discussions with Dr Powell, a "treatment plan" was prepared and that she agreed with what he proposed to do. The treatment plan was to increase her Warfarin from 4 milligrams to 4.5 milligrams, to enrol her in the QML program, and to consider a referral to a haematologist. She confirmed there was no question at that time of returning to see her cardiac specialist, Dr Garrahy.
[51]
[36] The plaintiff said that she was not aware of any factors that might have contributed to her INR instability and said that she also knew that, while she was in the hospital after having had the stroke, she encountered stability problems with her INR levels.
[52]
[37] The balance of the plaintiff's evidence went to matters of quantum, to which I will refer later in this judgment.
[53]
[38] Dr Powell's notes of his attendances on the plaintiff were tendered. They disclose, relevantly, that he saw her on 23 February 2002. In particular, his note for that day records:
[54]
[39] His note of his attendance on the plaintiff on 28 February 2002 (at 6.00 pm) records:
[55]
[40] In evidence, Dr Powell confirmed that prior to 1 March 2002 he did not have any specialist training, expertise or experience in Warfarin care. He said that on rare occasions he had been responsible for controlling Warfarin without the assistance of one of the specialist agencies, but it was not his common practice. He confirmed that, prior to 1 March 2002, he would receive paper copies of the plaintiff's INR test results "as a copy to doctor, but because we had paper files essentially it would arrive three or four days (sic: later) in the mail for perusal".
[56]
[41] Dr Powell said that if, prior to 1 March 2002, he had received a recommendation from the defendant to the effect that the plaintiff ought to receive particular treatment or be referred to her cardiologist, he would have followed their instructions. If he had been specifically informed that the plaintiff had become "a high risk case" he repeated that he would have followed their instructions "as they were the specialist carers for her Warfarin control". If the recommendation had been that she consult with her cardiologist, he would have referred her directly. Similarly, if it had been recommended that another drug, Clexane, be administered, Dr Powell would have followed their specialist instructions.
[57]
[42] Dr Powell referred to the notes of his consultation with the plaintiff on
[58]
23 February 2002. He confirmed that the plaintiff was concerned about her significant weight gain since her operation and they discussed the need to see a dietician for appropriate weight loss measures. He said that on that day he did not have any reason to believe that the plaintiff was a high risk patient in terms of her Warfarin care. He had a recollection that he was concerned that she "had a dangerously high INR some weeks prior to our discussion" and this needed to be taken into account when she saw the dietician. Dr Powell said that he was then contacted on 27 February 2002 by a female person from the defendant. He said this person did not introduce herself and he had the impression that he was being phoned by the Warfarin control adviser who rings patients. He said that she was ringing him and notifying him "of their decision not to monitor [the plaintiff's] Warfarin any longer". He could not recall the exact words used, but he was neither given a name nor a title of the person with whom he was speaking. He said: "I was merely informed that they would not monitor her Warfarin any longer".
[59]
[43] He said that this was not the type of conversation that he would expect to have with another medical practitioner. His best recollection of what he was told was:
[60]
"My recollection is I was told her Warfarin levels - her INR levels were erratic, they felt it was a consequence of non-compliance and they would no longer monitor her Warfarin."
[61]
[44] Dr Powell then described his attendance on the plaintiff on the evening of
[62]
28 February 2002. He had telephoned the defendant and obtained the plaintiff's latest INR, which was 1.7. He said:
[63]
"And considering her very high levels a couple of weeks previously on a smaller dose than she was on currently, I gently adjusted her Warfarin dose upwards and made a plan for her to be referred for specialist Warfarin control through Queensland Medical Laboratory, which is my usual practice, and we discussed that she was under a degree of stress and she must take great care with dieting."
[64]
[45] Under cross-examination, Dr Powell confirmed that, on 28 February 2002, having seen the INR of 1.7, his concern was that the INR had fluctuated downwards, but his biggest concern was that her current dose was a much higher dose than what she was taking when her INR was 7.0.
[65]
[46] Dr Powell was then cross-examined on his receipt of the plaintiff's blood tests. These "paper results" were mailed to him and then placed in a "large pile of seven doctors' worth of results to be placed in her chart". He said that as far as he was concerned, these were copies being sent to him, and he had never thought of himself as being in charge of the plaintiff's Warfarin control until it was left to him on
[66]
27 February 2002. He had no recollection of taking particular notice of any of the results, other than having seen a particularly high level of 7.0 at one time. His concern of an INR at that level was the risk of haemorrhagic stroke and this was why he then exercised caution when he prescribed the dosage of 4.5 milligrams.
[67]
[47] Dr Powell confirmed having a discussion with the plaintiff on 23 February 2002 about the instability of her INR, but related this in broad terms to his memory of her experiencing an INR of 7.0.
[68]
[48] In respect of the telephone conversation on 27 February 2002, it was put to
[69]
Dr Powell that he was speaking with Dr Beverley Rowbotham of the defendant, but he reaffirmed that he was not aware of who he was speaking to. In relation to the conversation itself, he gave the following evidence under cross-examination:
[70]
"Okay. Can I suggest that in the course of that conversation she told you that the defendant wished to discharge Mrs Papa to your care because it was believed that she was not suitable to be managed by a Warfarin clinic as it had not proved possible to maintain good control of her INR?-- No. My memory was that I was told by a female person that the patient was not compliant with their instructions and they would no longer control her Warfarin.
[71]
All right. I suggest that after the initial statement that I have just put to you it was explained that the reason for the transfer was because Mrs Papa's control was poor and that the defendant believed that she was non-compliant?-- Yes, that is - my memory was that they - she had - I was told she had erratic INR levels which they felt was a consequence of her being non-compliant, and they would no longer control her Warfarin.
[72]
Can I suggest it was discussed with you that as her personal physician it was believed by the defendant that you had a better chance of communicating with her the need for compliance and improved control and to affect that improved control and better compliance?-- No, that was never discussed. It was quite a brief discussion where I was told that due to her erratic INRs and non-compliance S & N would no longer control her Warfarin.
[73]
Is it true, doctor, that you didn't object to this referral of Mrs Papa back to your care? You made no protest in the course of the discussion?-- I was flabbergasted by their statements. I didn't know how to respond."
[74]
[49] Dr Powell also said that when he reviewed the plaintiff on 28 February 2002, he did not think of referring her to a cardiologist because he was not aware of any need for such a referral at that time.
[75]
[50] Dr Rowbotham, one of the principals of the defendant, is undoubtedly a highly qualified medical practitioner who has been a specialist haematologist since 1991. She was responsible for the establishment of the WCS. She described the history of its establishment and said that, in 2001, the WCS had five haematologists and 5,000 patients on the books. She described the processes followed when a patient entered the WCS, with provision of the booklets and the obtaining of information from the pathology tests. She described the processes followed by haematologists in referring to information provided on the computer screen, and the high degree of reliance placed by her and the other haematologists on the self-reporting by patients on matters such as bruising, diet and sickness. These matters were identified in the clinical notes flagged on the screen. She said that once the haematologist had identified the appropriate dosage and the next testing date, that information was passed down the line to the particular employee who communicated with the patient. She confirmed that the defendant did not actually prescribe the medication, but was delegated the responsibility of dosing.
[76]
[51] Dr Rowbotham said that her perception in 2001-2002 was that one could expect there to be a number of patients in and out of their target ranges at any particular time. She said that she knew that roughly 60-65 per cent of the patients were within range at any one time, 25 per cent were below range and the remainder above range. This disparity between the sub-therapeutic and above therapeutic numbers was described by her as a "universal phenomenon". She said:
[77]
"In all the series that are reported, it's always skewed to being below range in the management of the patients and this is because of the fear of bleeding, that patients will be over anti-coagulated and bleed. As doctors, it's a terrible responsibility to cause a new illness, and that is what Warfarin does. It may address one illness - a thromboembolic disease - but it carries the risk of a new illness, bleeding."
[78]
[52] She said that whilst the aim was to get patients within the target range, retrospectively one saw that one dosed conservatively, that is lower rather than higher.
[79]
[53] By reference to the records, Dr Rowbotham confirmed that she had been the dosing haematologist on two occasions in early January 2002 and then on 16, 19, 22 and 25 February 2002. She was asked in relation to her first attendance on 7 January 2002 whether she actually recalled the incident when she examined the records for the patient on that day and made her prescription and said:
[80]
"No, I don't. If I was on dosing duty I would dose perhaps a hundred patients in a day and so I would not recall any individual patient usually, but I'm very well aware of my practice. I had been dosing Warfarin for 10 years at that point and I had an established way of doing it and all my colleagues had the same pattern. We had made that a policy because patients could expect to be dosed by any of us whenever they presented and it was important we had a consistent approach, so I'm happy to talk to the dosing by my colleagues as well."
[81]
[54] She then said that she would speak to her own dosages from the practices she had established over many years.
[82]
[55] She referred to the plaintiff's high INR of 5.9 on 3 January 2002 as being explained by the New Year, saying this was a time of year when high readings were often seen, and were attributed to the Christmas season and changes in diet and alcohol intake. She said it was not uncommon for there to be a single elevated INR at that point in the year. She noted a report of heavy bruising by the plaintiff on that day. She said the high INR indicated over anti-coagulation, which had precipitated bruising and bleeding into the skin. She referred then to the plaintiff's INR readings of 5.9 on 3 January 2002 and 5.7 on 10 January 2002, noting that there were two episodes of high INR with bruising, and the risk associated with bleeding, saying that she would be "worried about intracranial bleeding". She repeated that there was a great responsibility in dosing Warfarin not to replace one disease with another:
[83]
"... for a patient to come to harm from over anti-coagulation as part of a treatment for another disease weighs very heavily on any of us who dose Warfarin. And we are well aware that the risk of bleeding increases once the INR gets above four, and once it goes above five it starts to increase exponentially. And in major series the bleeding rate in - major bleeding rate is something like two per hundred patient years and the intracranial haemorrhage rate is something like 0.5 per hundred patient years and that, of course, is the thing that worries us the most. It's a devastating condition, an intracranial bleed. Nearly half the patients die within a month. More than two-thirds are left with a serious morbidity if they have survived, and ... it's a very bad outcome."
[84]
[56] She then described her perception of risk at the sub-therapeutic level, and spoke specifically about patients with mitral valve replacements. She referred to the risk of haemorrhagic stroke at the over anti-coagulated extreme and the equivalent risk of ischemic stroke at the under anti-coagulated extreme. She said, however, that there was a further increase in adverse events at the high end because of major bleeding, which might be in the head, but might also be fatal gastrointestinal bleeding.
[85]
[57] Dr Rowbotham said that a practice of administering Vitamin K as an antidote to Warfarin in cases where the INR was too high had been ceased after requests from cardiac surgeons. What was left for the purposes of control was to omit doses and then restart the Warfarin treatment at lower doses until control of INR levels was regained.
[86]
[58] Dr Rowbotham then spoke to the testing and dosing which had been undertaken by her colleagues, noting that Warfarin had to be managed prospectively, i.e. one prescribed a dose and then had to wait and see what effect it had. She was referred to the INR reading of 7.0 on 9 February 2002, saying:
[87]
"But by this time we've got a track record throughout the whole of January of four INR's up around the levels at which the risk of bleeding is documented in the literature as being very high. So this is - this is very concerning."
[88]
[59] Dr Rowbotham then described in some detail her involvement in the testing and dosing procedure on 16, 19, 22 and 25 February. She referred to the "spikes" which had been noted and to balancing the relative risks of bleeding and thrombosis, of the presence of the mechanical mitral valve and the risk of another spike up. She described the significance of the plaintiff having "spiked" when administered average doses of 3.71 milligrams, and said:
[89]
"So I'm trying to now to return her INR from 1.5 to the reference range and how one would do that is to step the dose up gradually and test frequently and the only bearing one had was to look at her record over the last month and to see what doses were associated with those overshoots that she had experienced and, on review, that is 3.71 milligrams on two occasions."
[90]
[60] Dr Rowbotham referred to a clinical note on 9 February 2002 of the plaintiff having suffered from a virus and said she took this into account. She then described the process of incrementally increasing the dosages of Warfarin over the following attendances - a process she described as "cautiously increasing the dose". When asked about the INR of 1.6 on 19 February 2002 and what this indicated to her, Dr Rowbotham said:
[91]
"Well, we needed to increase the dose again and again this is not surprising, this - the Warfarin therapy has been in a state of flux for some time. Stopping and starting Warfarin therapy is a very tricky game. It's certainly not like turning on and off a tap. The Warfarin levels need to fall and, beyond that, the clotting factors that Warfarin influences will recover at different rates, so that it's - it's really very difficult to predict how fast INR's will return to the reference range once you've stopped and started Warfarin a couple of times."
[92]
[61] In relation to the INR of 1.5 of 22 February 2002, she said that it indicated she needed to increase the dose again. She observed that there had been a huge swing from an INR of 7.0 to 1.5 in a seven day period, and referred to the length of time it takes for Warfarin to escape the system and the return of clotting factors.
[93]
[62] Dr Rowbotham rejected micro-management of the dose by giving a "stat" dose of Warfarin, saying that she considered "stat" doses unreliable and that the administration of a "stat" dose in an already unstable situation compromised her ability to estimate where the level would land. She identified a particular danger with stat doses being that one could land "too high".
[94]
[63] Dr Rowbotham was asked about her perception of the plaintiff's risks of suffering a thromboembolic event and a haemorrhagic event in the particular circumstances in which the doctor was examining these results. Her evidence was as follows:
[95]
"What I'm asking you is to give your opinion or - sorry - your understanding-----?-- Yes.
[96]
-----at the time as to the risk of a thromboembolic event being faced by Mrs Papa?-- Yes.
[97]
And I'll be going on to ask you the corresponding question in relation to haemorrhagic events?-- Yes. Certainly I perceive Mrs Papa as having a risk of a thromboembolic event. She had a mitral valve, an artificial mitral valve. In scaling, in assessing the - well, can I say first up that there's very little literature which will allow to you actually predict anybody's risk of thrombosis, or of bleeding in a - in this setting, as the literature is all retrospective, but - but then let me say, when I was thinking about Mrs Papa, certainly I perceived her as being having a risk of thromboembolism. She had a mechanical mitral valve. Where she lay on the risk of thromboembolism, I took into account the fact that she was a young woman, which was in her favour, reduces her risk of thromboembolism. She had a modern mitral valve. She did not have atrial fibrillation or heart failure, or a previous history of stroke, and she was not in the first three month of Warfarin therapy, all of which are markers for increased risk of thromboembolism in patients with mitral valves. So, on that scale, I saw her as having a lower risk of thromboembolism if one was dividing up mitral valve risk into - into gradations.
[98]
All right, and as to haemorrhagic events, how did you perceive the risks there?-- Yes. Well, I saw her as having a significant - also having a significant haemorrhagic risk. She had had - her last spike of an INR of 7, led me to believe that it was at least two week period at which she was an increased risk of bleeding, from the literature, and I wasn't sure why it would stop at two weeks. I thought it would probably - you know, there was - it was reasonable that risk continue beyond a certain point, so I hadn't - I had - I believed there was an increased risk of bleeding for at least two weeks. I was also worried about her tendency to spike and I was concerned she would do this again and that would again put her at risk of bleeding.
[99]
Thank you. All right, and can you, in balancing those risks, indicate which you thought was the greater?-- I thought the greater risk was the risk of bleeding and certainly the consequence of bleeding, which was intracranial haemorrhage, was the thing that worried me greatly."
[100]
[64] Dr Rowbotham described the INR of 1.8 on 25 February 2002 as the "kick up" that she had been waiting for, and said that she again increased the dose. She said that she thought "we were on the road back".
[101]
[65] It is convenient to set out here Dr Rowbotham's evidence about the use of low molecular weight Heparin or unfractionated Heparin as supplementary anti-coagulants (the further significance of this evidence will become apparent when I discuss the expert evidence):
[102]
"Now, Dr Robothom are you able to say whether during this period you considered prescribing or suggesting to anyone that low molecular weight Heparin or unfractionated Heparin be administered?-- No. I didn't consider prescribing it myself because that is not my usual practice and neither did I consider suggesting it. My usual practice in a patient who is underanticoagulated is to step up the dose, as I have here, in the expectation that it will reach the reference range eventually and many patients will do that promptly and in some it is slower and certainly it was slower in this case. That is my usual practice and I believe that to be usual practice still today in the literature. I would not have used low molecular weight Heparin in this patient because of the risk of bleeding that I perceived and I was not aware at the time of any literature to suggest that low molecular weight Heparin should be used in underanticoagulated outpatients and certainly there was no specific guidance on this specific difficult management issue of a patient who is underanticoagulated but still has a risk of bleeding.
[103]
Were you aware that Heparin might be used by some clinicians in this situation? Were you aware of any usage of it at all in this situation?-- Yes. Theoretically there are a range of anticoagulants which could be used in patients who are underanticoagulated, so one canvasses that list whenever one sees a patient who is underanticoagulated, but usual practice, and certainly my practice, would not have been to use Heparin in this patient who had a risk of bleeding and whose thrombotic risk I considered to be on the lower end of the scale for mitral values."
[104]
[66] Dr Rowbotham was then asked about her knowledge of the relevant published guidelines and other medical literature concerning the management of patients on anti-coagulant medication. She said that it was usual or common practice in the case of under anti-coagulation for the dose of Warfarin to be increased until one achieved control. Further, in the context of administering low molecular weight Heparin, Dr Rowbotham identified another reason for not using that anti-coagulant, saying:
[105]
"Well, specifically the risk of haemorrhage in this patient, so it's a - it's a different setting to a patient with a low INR. It's a patient with a low INR who also has bleeding risk and so there was even - there was nothing in the literature to guide the relative risks in that - that setting. It came down to my clinical judgment and I weighed the risks of thrombosis and the risks of bleeding and I believed her to have a significant risk of bleeding and that low molecular weight Heparin would add to that risk of bleeding because of its long half life and the fact that there was no way of reversing it should over anti-coagulation occur."
[106]
[67] Dr Rowbotham's evidence in chief concluded with her giving evidence about having telephoned Dr Powell. She said she recalled having this discussion, because she did not phone very many general practitioners to discharge patients. She said she expressed the view to Dr Powell that the plaintiff's control had been very poor, as he would have known from the results which had been coming to him. She told him that she needed to bring that to this attention and that she did not consider the plaintiff to be a suitable person to be cared for on the defendant's program. She told Dr Powell that she thought that compliance was an issue and that she hoped that the plaintiff's control would be better in a one to one relationship with Dr Powell. She said that there was no significant response from Dr Powell, that he accepted her advice and recommendation and said that he would see the plaintiff later that day.
[107]
[68] Under cross-examination, Dr Rowbotham said that a belief that the plaintiff was not complying with her Warfarin care regime was part of the reason for discharging her. Dr Rowbotham said that she had formed the opinion that compliance by the plaintiff "could well be an issue" and her decision to discharge was based on the hope that compliance would improve in a different setting. She said that this decision was not based on an assumption, but was a conclusion that she had reached after reviewing the plaintiff's records.
[108]
[69] Dr Rowbotham confirmed that the plaintiff's case presented a difficult management problem for her because of the need to balance the risk of a thromboembolic event with the risk of a haemorrhagic event. She said that by 22 February 2002, the gradual increases in the doses of Warfarin were not achieving the desired results. When challenged, she said that she had considered alternative forms of anti-coagulation from the time the INR was 1.5.
[109]
[70] She also confirmed that although one of her concerns was of the risk of haemorrhagic event, this was not something that she discussed at any time with the plaintiff.
[110]
[71] Dr Rowbotham was asked about the plaintiff's report of heavy bruising on
[111]
3 January 2002 and described it as part of the pattern that emerged throughout January. She said that, even if the plaintiff had not reported that clinical matter,
[112]
Dr Rowbotham would still have been very concerned about the pattern of INR's throughout January, and that it was all part of important and relevant clinical information.
[113]
[72] Dr Rowbotham said, however, that by 22 February 2002, even though she had concerns about the plaintiff's increased risk of thromboembolic event, she had not telephoned the plaintiff to advise of this risk because it was not the defendant's usual practice to ring the patient about these matters. She said that, traditionally, they would not ring the patient with every high INR to talk to them about the results. She referred to seeing the plaintiff as being at risk of a thromboembolic event and also a risk of bleeding and said that while she did not ring the patient, she rang the doctor. When questioned further on her discussion with Dr Powell, she said that she did tell him that she was ringing about the plaintiff's very poor control on the program and that the plaintiff had been high and low and about the risks that were entailed. She was challenged that she had not introduced herself as a doctor and haematologist from the defendant and denied this flatly, saying that she would never not introduce herself in a phone call to another doctor. It was put to her that after not introducing herself, she then went on simply to say that she was discharging the plaintiff to Dr Powell's care because she believed that the plaintiff was not suitable to be managed by the defendant as it had not proved possible to maintain good control of the plaintiff's INR's. Dr Rowbotham said that this was a "short version" of what she said.
[114]
[73] The particulars of negligence and breach of contractual duty which the plaintiff advanced against the defendant at trial were as follows:
[115]
"(a) failure to do anything other than increase the dose of warfarin during the period 13 - 27 February 2002;
[116]
(b) failure to adequately and properly communicate the difficulty in controlling the plaintiff's INR to the plaintiff and/or alternatively to the plaintiff's general practitioner and/or alternatively to the plaintiff's cardiologist, either orally or in writing, and particularly during the period 13 - 27 February 2002, when repeated sub-therapeutic readings were obtained on 13, 16, 19, 22 and 25 February, and when there was a considerably increased risk of thromboembolism, and when the plaintiff's history suggested or indicated that the re-establishment of control could be prolonged;
(c) failure to recommend to, request or advise the plaintiff's general practitioner and/or cardiologist, either orally or in writing, that the plaintiff should be started on Heparin or Clexane, and/or alternatively failing to advise the plaintiff's general practitioner and/or cardiologist that they should consider starting the plaintiff on Heparin or Clexane given that repeated sub-therapeutic readings were obtained on 13, 16, 19, 22 and 25 February 2002 and when there was a considerably increased risk of a thromboembolism, and when the plaintiff's history suggested or indicated that the re-establishment of control could be prolonged;
(d) failure to adequately and properly advise the plaintiff that she was at a considerably increased risk of thromboembolism when repeated sub-therapeutic readings were obtained on 13, 16, 19, 22 and 25 February 2002;
(e) failing to make any or any proper or reasonable attempt or attempts to determine or ascertain or alternatively have determined or ascertained whether there was an underlying medical reason for the instability of the INR;
(f) failing to advise or adequately and properly advise the plaintiff that:
[117]
(i) from 3 January 2002 to 27 February 2002 there was extreme difficulty in managing the plaintiff's care with INR response to a prescribed dose of warfarin of 3-4mg varying from 1.50 to 7.0; and/or
[118]
(ii) during the period 13 - 27 February 2002 repeated sub-therapeutic readings were obtained on 13, 16. 19, 22 and 25 February which gave rise to a considerably increased risk of thromboembolism with potential disastrous complications such as a stroke; and/or
[119]
(iii) the plaintiff should seek medical and/or alternatively specialist medical opinion to determine whether there was an underlying medical reason for the instability of the INR.
[120]
(g) permitting and allowing the plaintiff to remain exposed to a considerably increased risk of thromboembolism with potential disastrous complications such as a stroke, that could have been avoided by the exercise of reasonable care on its part;
(h) failing to observe or appreciate that the plaintiff was in a position of peril as a consequence of being exposed to a considerably increased risk of thromboembolis with potential disastrous complications such as a stroke, which in fact occurred to the plaintiff."
[121]
(a) If the defendant had advised the plaintiff, her GP or her cardiologist of any of the matters referred to in the particulars, the plaintiff would have acted upon such advice, particularly given the considerably increased risk of thromboembolism with sub-therapeutic INR with potential disastrous complications such as a stroke; and
[122]
(b) Further, or alternatively, if the defendant had given any of the advice referred to in the particulars to the plaintiff, her GP, or her cardiologist, Heparin or Clexane would have been added to the plaintiff's Warfarin therapy, as a consequence of which, she would not have suffered the stroke.
[123]
[75] These allegations raise for consideration the content of the duty owed by the defendant to the plaintiff, and the conduct required of the defendant to meet the necessary standard of care, particularly in respect of:
[124]
(a) The way in which the defendant managed the plaintiff's dosage levels in the period 13-27 February 2002, and
[125]
(b) Any advice which the defendant ought to have given the plaintiff and her doctors, including advice as to the use of Heparin or Clexane.
[126]
[76] There are also, clearly, questions as to whether any proven breach of duty was causative of the stroke, and thereby of the loss suffered by the plaintiff.
[127]
[77] The defendant denied the allegations of negligence, contending:
[128]
(a) It acted appropriately and in accordance with good medical practice in taking the steps that it did;
[129]
(b) The addition of Heparin to the plaintiff's treatment regime would have required in-patient treatment;
[130]
(c) The addition of Heparin or Clexane to the plaintiff's treatment regime was not reasonably required because:
[131]
(i) at the relevant times, these drugs were not known or generally recommended, as appropriate treatment in addition to Warfarin, nor was there any accepted guideline for the use of those drugs in that application for a person with the plaintiff's medical condition, particularly with uncontrollable INR;
[132]
(ii) if the plaintiff had been prescribed Heparin or Clexane she would have been at an increased and unacceptable risk of suffering serious haemorrhage and other complications.
[133]
[78] In Rogers v Whitaker[3] the majority of the High Court authoritatively stated the duty of care owed by a medical practitioner in the following terms:[4]
[134]
"The law imposes on a medical practitioner a duty to exercise reasonable care and skill in the provision of professional advice and treatment. That duty is a 'single comprehensive duty covering all the ways in which a doctor is called upon to exercise his skill and judgment'; it extends to the examination, diagnosis and treatment of the patient and to the provision of information in an appropriate case. It is of course necessary to give content to the duty in the given case.
[135]
The standard of reasonable care and skill required is that of the ordinary skilled person exercising and professing to have that special skill ..."
[136]
[79] In determining the standard of care required to observe the duty, the majority said:[5]
[137]
"The duty of a medical practitioner to exercise reasonable care and skill in the provision of professional advice and treatment is a single comprehensive duty. However, the factors according to which a court determines whether a medical practitioner is in breach of the requisite standard of care will vary according to whether it is a case involving diagnosis, treatment or the provision of information or advice; the different cases raise varying difficulties which require consideration of different factors. Examination of the nature of a doctor-patient relationship compels this conclusion. There is a fundamental difference between, on the one hand, diagnosis and treatment and, on the other hand, the provision of advice or information to a patient. In diagnosis and treatment, the patient's contribution is limited to the narration of symptoms and relevant history; the medical practitioner provides diagnosis and treatment according to his or level of skill. ... Whether a medical practitioner carries out a particular form of treatment in accordance with the appropriate standard of care is a question in the resolution of which responsible professional opinion will have an influential, often a decisive, role to play ..."
[138]
[80] As was subsequently made clear in Rosenberg v Percival[6] reference by the Court to evidence of professional practice and opinion will be relevant, but not conclusive, in respect of the Court's determination of the content of the duty owed by a treating doctor and the steps required to meet that duty.[7]
[139]
[81] It is also important to remember that one must adopt a prospective, and not a retrospective, perspective when enquiring into these matters. The resolution of the question as to whether there was breach of duty "is not to be undertaken by looking back at what has in fact happened, but by looking forward from a time before the occurrence of the injury giving rise to the claim".[8]
[140]
[82] It is therefore necessary to review the expert evidence led on these liability issues by both the plaintiff and the defendant.
[141]
[83] Professor Fox is, among many other notable appointments, a professor and the director of the Department of Clinical Haematology and Medical Oncology within the Royal Melbourne Hospital at the University of Melbourne. He is, as his title would suggest, a specialist haematologist oncologist. He provided a number of reports and gave oral evidence before me.
[142]
[84] In a report dated 24 June 2005, Professor Fox expressed the following opinions:
[143]
(a) That on establishment of erratic INR results it would be appropriate for a pathology service to alert the responsible doctor;
[144]
(b) In the context of answering a question as to matters which ought to have been undertaken by Dr Powell (not relevant for this proceeding), Professor Fox noted that when Dr Powell saw the plaintiff on 23 February 2002, her IRN had become relatively stable, albeit at a low level (between 1 and 2) "and at this point an increase in the dose of Warfarin would have been appropriate, or the use at that time of a Heparin compound".
[145]
[85] In a further report dated 25 October 2005, Professor Fox expressed the opinion that if the plaintiff's INR had been at about 3.0, then on the balance of probabilities, the plaintiff would not have suffered a stroke. He also criticised the defendant's provision of medical services to the plaintiff because he believed that they did "not appear to have communicated sufficiently with her general practitioner to note the problem of difficulty in control of her INR".
[146]
[86] Professor Fox provided a further report dated 26 April 2007, having received in the interim a copy of a report by one of the defendant's experts, Professor Metz (see below) and certain other documentation. Professor Fox agreed with Professor Metz that, having regard to the plaintiff's prior high INR and the danger zone for bleeding, that it was appropriate for the defendant to increase the dose of Warfarin cautiously.
[147]
[87] Professor Fox went on to criticise the defendant, however, saying that it "would have been appropriate" for the defendant to have entered into discussion with the plaintiff's general practitioner saying that the defendant "should have verbally communicated with Dr Powell that there was a difficulty in controlling [the plaintiff's] INR, but not to have, using their term, "expelled" her from the clinic".
[148]
[88] Professor Fox was also asked to comment on whether the plaintiff should have been started on Clexane because of her low INR results. He said:
[149]
"Clexane is a form of Heparin which is sometimes given if the INR is low and there is a risk of thromboembolism. It is a direct anticoagulant. Responsibility of administration of these would be the caring physician rather than the pathology lab. That could be a general practitioner or a specialist."
[150]
He again referred, in this context, to the fact that some communication with the GP "would have been appropriate by direct telephone call".
[151]
[89] Further, Professor Fox said that, as a specialist clinical haematologist, if the plaintiff had been referred to him on 13 February 2002 or a subsequent date when her INR's remained at sub-therapeutic levels, the most appropriate treatment, in his belief, would have been Clexane administration.
[152]
[90] In oral evidence before me, Professor Fox confirmed that he had been in clinical practice as a haematologist oncologist for some 35 years, and during that time he had treated and consulted with persons on Warfarin therapy. He thought he had about ten such patients at any one time and, therefore, had treated some couple of hundred patients over the years. In response to a suggestion by one of the other specialists that it would have been dangerous to add Clexane to the plaintiff's Warfarin therapy, Professor Fox said that he did not agree that it was a dangerous process and referred to medical literature which cited Clexane as having been used as a "bridging therapy". Professor Fox did not think there had been claims of increased danger in that process.
[153]
[91] Under cross-examination, however, it emerged that Clexane was not recommended by its manufacturer for use as an anti-coagulant in conjunction with a prosthetic mitral valve. He was also referred to a statement in the 2001 edition of MIMS Pharmacology to the effect that:
[154]
"There have been no adequate studies to assess the safe and effective use of [Clexane] in preventing thromboembolism in patients with prosthetic heart valves. The use of [Clexane] cannot be recommended for this purpose."
[155]
[92] Whilst Professor Fox said that this passage in MIMS did not exclude the use of Heparin, he agreed that it said that the use of Clexane was not recommended.
[156]
[93] Professor Fox was also cross-examined on a number of academic medical articles which supported the proposition that the conventional approach to treating sub-therapeutic INR in 2001/2002 was to increase the cumulative dose levels by 10-20 per cent. Professor Fox said that he thought this depended on the individual circumstances of the patient. He referred to the required exercise of clinical judgment, and criticised the defendant for "expelling" the plaintiff from the program. He expressed the view that this case constituted "exceptional circumstances".
[157]
[94] Professor Fox was then cross-examined on the comparative risks of a thrombotic stroke occurring in a sub-therapeutic INR situation and a haemorrhagic stroke occurring in an above therapeutic level situation. He agreed with the propositions that, in the usual case, the mortality from an haemorrhagic stroke was higher than that from a thrombotic stroke, and that morbidity from an haemorrhagic stroke is usually greater than the morbidity of a thromboembolic stroke. He pointed out that an haemorrhagic stroke is rarer than a thromboembolic stroke and agreed with the proposition that one has a "rarer but more serious complication from the over anti-coagulation than under anti-coagulation".
[158]
[95] When it was put to him that once an INR level is more than 5, the risks of haemorrhagic stroke increased quite exponentially, he agreed that they "increase significantly". He also agreed that, in comparison, the risk of an embolic stroke, when one is anti-coagulated at INR levels 1.5 - 1.9 has an incidence which is much less than the incidence of haemorrhagic stroke in patients whose INR is greater than 6.0. By reference to research on which Professor Fox was cross-examined,[9] it emerged that the percentage risk of a patient suffering an haemorrhagic stroke increased from about 10 per cent to 20 per cent in the rise in INR from 5.9 to 6.4, but from 6.4 to 6.5 the percentage risk increased from 20 per cent to 75 per cent.
[159]
[96] Professor Fox was cross-examined on the plaintiff's INR readings and dosages from 16 February 2002. He regarded the dosing through to 19 February 2002 as reasonable and appropriate, and said that by 22 February 2002 he would be wanting to investigate what was going on.
[160]
[97] It was then put to him that the administration of Clexane would have carried a very significant risk of over anti-coagulation. He was later cross-examined on the plaintiff being administered Clexane when her INR was unstable after having suffered the stroke and sought to distinguish the beneficial effect of Clexane. He said:
[161]
"It probably meant that her INR was unstable for terms that we don't understand in terms of Warfarin metabolism, but the Clexane was probably preventing any further progression of the clotting process or embolic process that had led to the stroke. And the issue is, of course, if Clexane had been administered a little bit earlier during this period of unstability that it may have prevented her stroke."
[162]
[98] It was specifically put to Professor Fox that there was no protocol, guideline or published, peer-reviewed paper which recommended or mandated the use of Clexane in a patient whose INR levels had become sub-therapeutic. He agreed with that, but said:
[163]
"However, there are circumstances in medicine that frequently arise where you don't have a little formula to follow exactly. You have to use ad lib and a judgment as to how you're going to get through a set of circumstances, and that usually happens about every day."
[164]
[99] He then agreed that the case which presented here was a "difficult clinical situation".
[165]
[100] He also agreed with the proposition that if a patient in the same situation as this plaintiff, with the same history of "spiking", bruising and unstable INR, had, in additional to Warfarin, been administered Clexane and then suffered an haemorrhagic stroke, the case against the doctor "would be indefensible".
[166]
[101] Professor Fox also postulated the utility of administering a "stat" dose, which would immediately have had an anti-coagulant effect.
[167]
[102] In re-examination, Professor Fox confirmed his view that the practitioner who needed to exercise judgment in a particular case as to whether to prescribe Clexane was, in a case such as the plaintiff's, her cardiologist. By reference to the sub-therapeutic readings which started occurring on 13 February 2002, Professor Fox said that he would have referred the plaintiff to the cardiologist after her second or third low reading. He would not necessarily have formally referred her, but at least would have had a telephone discussion with the cardiologist.
[168]
[103] Dr Davidson is a highly qualified haematologist, and is the head of QML's haematology department. In a report dated 20 November 2008, Dr Davidson was referred to the sub-therapeutic readings between 13 and 25 February 2002 and asked whether he would have recommended to, requested or advised the plaintiff's general practitioner and/or cardiologist that the plaintiff be started on Heparin or Clexane. He reported:
[169]
"If it is apparent that after 5-7 days, that some warfarin resistance is present, AND the INR remains ≤ 1.5 AND the INR is less than LowTarget - 1.0, the use of bridging anti-coagulation must be considered and perhaps used until the INR approaches to within 0.5 of the Low Target. Bridging anticoagulation may take the form of oral aspirin or heparinization. Heparinization is often preferred in high-risk conditions (e.g. Mitral Valve Replacement in contrast to Aortic Valve Replacement). Heparinization is commonly achieved in the outpatient setting using a Low Molecular Weight Heparin such as Clexane, which is easily administered by the patient or their general practitioner. A verbal or written order to prescribe clexane is usually directed toward the patients general practitioner."
[170]
[104] Dr Davidson also expressed the opinion that some form of bridging anti-coagulation (referring to Heparin or Clexane) "would have reduced the risk of thromboembolism and it is probable the stroke would have been avoided". He added, however, that it was important to note that the risk is never eliminated.
[171]
[105] In a memorandum of a subsequent discussion with Dr Davidson, his further opinion was recorded that there was no written protocol for management of patients with sub-therapeutic INR, that the management of sub-therapeutic INR levels requires a clinical judgment based on the risk of the patient developing a clot, and that the factors for consideration are the INR results, the target range, the patient's condition and whether there is any delay in being able to get the INR into the target range. He said that not all GP's are up to date in managing complex anti-coagulation problems and would probably need some guidance. He said that one could not treat all GP's as knowing what to do and that guidance/advice to the patient and GP was part of the Warfarin care service.
[172]
[106] Dr Davidson then made comment on each of the sub-therapeutic INR readings from 13 February 2002. In relation to the INR result of 1.5 on 22 February 2002,
[173]
Dr Davidson said that by this time the INR results had been low for almost a week. He said that "a week of sub-therapeutic readings would have rung alarm bells for any specialist", and that "a mitral valve is much more concerning at these levels".
[174]
[107] Dr Davidson posited the prospect of administering "stat" doses, even from
[175]
13 February 2002. By 22 February 2002, he said that he would have been considering bridging therapy, that the type of bridging therapy would depend on the circumstances. For a patient with an artificial mitral valve, he would have looked at giving her Clexane. He said:
[176]
"QML's practice would be to get in touch with the patient and tell them to attend the GP and they would then call the GP to advise him to administer Clexane. In 2002, this would simply have been a verbal communication but now they have a written pro-forma order that goes to the GP for the administration of Clexane."
[177]
[108] In cross-examination, Dr Davidson agreed that in the period beyond
[178]
13 February 2002, a pathologist who, in the face of low INR's, below 2.0, progressively increased Warfarin dosage in small measures was "following the conventional wisdom". He also acknowledged that it would be a worry for the clinician that there had been a six week period of instability, and that a dose of between 3 and 4 milligrams of Warfarin had produced an INR of 7.0. He said it came down to "sort of judging then after a week of not progressing anywhere that maybe we need to be a bit more aggressive with our dosing". He confirmed also that the requirement to give a "stat" dose was a judgment to be made by a clinician. Similarly, he thought that if the INR had not really budged after a week or so then he would definitely need to consider some form of bridging therapy, with Clexane to be given in addition to the Warfarin. He also agreed that the practice of providing coverage with Clexane during the course of Warfarin therapy varied from specialist to specialist, that there was no protocol even at QML for the use of Clexane as a bridging therapy, and that the use of Clexane by him in this application was "very much a personal choice" by him. He went on to suggest, however, that he considered himself to be conservative, and that other haematologists would have used Clexane at an earlier stage. He said:
[179]
"I think, as I said, I'd allow 5 to 7 days, particularly coming off an unstable period, to actually show what the INR's doing before considering sort of needing bridging therapy. So I think after a week there where we still have an INR that's sort of one below the ideal lower range of the target you'd be concerned. Certainly if I was - if I was considering myself as the patient with a valve, I think I'd probably be more cautious and cover myself. It comes down to a decision if it was me I would want extra cover because the consequences can be catastrophic."
[180]
[109] He agreed that there was no "hard and fast rule" and that each individual case had to be judged on its merits and that the main risk of a high INR was the haemorrhagic risk. He referred to the process as a "delicate balancing act", and acknowledged that with INR's close to or beyond 6.5 there is a risk of a major bleeding incident which is higher than the risk of a thrombotic event. He also conceded that if the plaintiff's INR had remained out of effective control and she was then covered with Clexane as well, there was a risk that she would have been grossly over anti-coagulated, and that if there had been another spike in the INR while Clexane was being administered, the risk of an haemorrhagic outcome was "certainly highly increased". With reference to the incremental increases in dosages administered by the defendant, he said that he could "understand the caution given the previous instability". He was also referred to a particular medical publication which suggested that, except in exceptional circumstances, most patients do not need to be covered with a rapidly acting anti-coagulant, such as Heparin or low molecular weight Heparin, but rather the weekly cumulative dose of Warfarin should be increased by 10 to 20 per cent. He said:
[181]
"I think you have to look at the stability of the patient beforehand. Certainly patients who seem to be stable and just throw out one INR that's out of target range and there doesn't appear to be any obvious explanation, or they may admit to - they missed a dose, I think, you know, it's quite reasonable not to hit the panic button because you know that the - more than likely the INR will return into range just with the resume of regular dosing. Where the patient's being a little bit unstable and again - which was the case preceding the 13th February, you'll probably be a little bit more cautious and again, looking at the case individually, how sub-therapeutic were they? A lot of the studies have looked at sub-therapeutic INR's that have just been all relatively mildly sub-therapeutic, maybe 0.5 to 1, and again these patients have been relatively stable in their INR beforehand, and again one could then assume that they would return to a stable dose. But I think when you're dealing with INR's that are very sub-therapeutic, as in - I think Mrs Papa's targeted INR range was 3 to 3.5 or even 3 to 4, and when you're dealing with INR's in that case, less than 2, for more than a week I'd be concerned."
[182]
[111] Dr Davidson did, however, confirm that, outside the use of Heparin in the context of Warfarin therapy in a perioperative situation (i.e. when a patient under Warfarin therapy is about to undergo surgery), there was no guideline, published protocol or published sanction for the administration of Clexane in conjunction with Warfarin to correct or cover low INR's as at 2001/2002.
[183]
[112] Dr Garrahy, the director of cardiology at the Princess Alexandra Hospital, is the plaintiff's cardiologist. In a report dated 19 November 2008, he said:
[184]
"Specifically in regard to the standard clinical response to a sub-therapeutic INR in a patient with a mechanical mitral valve prosthesis, I advise that standard therapy would be to institute anti-coagulation with Heparin and this would certainly have been my clinical recommendation with the second sub-therapeutic INR on 19/2/2002. Appropriate advice for her on that day would have been to either institute sub-cutaneous Clexane (1 mg/kg twice daily) or to be admitted to hospital for intravenous unfractionated Heparin infusion.
[185]
The usual therapeutic range advised for a mechanical mitral valve prosthesis is an INR between 2.5 and 3.5. The recommendations to "cover" a mechanical mitral valve in clinical situations requiring the withdrawal of Warfarin are that Heparin is commenced once the INR falls below the therapeutic target range. Most clinicians would become somewhat concerned in such a patient with a mechanical prosthesis with an INR below 2.0, quite definitely with an INR below 1.8. To have obtained two INR readings below 1.8 over a period of three days would certainly flag an increased risk for valve associated thrombus formation, and systemic embolism."
[186]
[113] In evidence before me Dr Garrahy confirmed that in February 2002, there was nothing to prevent him from seeing the plaintiff if she needed to consult with him.
[187]
[114] Under cross-examination, Dr Garrahy said that while the product literature did not contain a recommendation for the use of Clexane with prosthetic valves, the practical situation may have required, for example, the admission of the patient to hospital to give them unfractionated Heparin, but that itself would have involved the risk of getting a bed quickly for that patient and also the risks of drip site sepsis. He said the practice of medicine was a balance of risk and benefit: "it's not a cookbook". He was referred to the substitution of Heparin for Warfarin in patients about to undergo surgery, and agreed that it was uncommon to see patients who were having difficulty with their INR levels, but he did see them. In the cases of such instability, he would not simply defer to a haematologist. He said that, as a cardiologist, if he saw a patient with a mitral prosthetic valve and an INR of 1.5, he would regard this as a "red alert". He also went into detail about the way in which he would administer unfractionated Heparin, referring to the American College of Cardiology guidelines, and noting that management of anti-thrombotic therapy must be individualized.
[188]
[115] Dr Garrahy conceded that the bridging therapy would give rise to a risk of bleeding but said this was why one would have the patient under observation in hospital with close supervision of the medications.
[189]
[116] Dr Turnbull, a general practitioner, provided reports in relation to the role in this case of Dr Powell. He said that he considered that a review of the documents provided to the plaintiff about the defendant's service indicated that the defendant was assuming full responsibility for performing the INR tests and advising the plaintiff of Warfarin doses. He considered it important that Warfarin doses be managed by only one entity and said that he considered that Dr Powell was entitled to assume that the defendant was competent in managing the plaintiff's INR variability. Dr Turnbull said that any reasonable general practitioner would administer Clexane if recommended to do so by a Warfarin monitoring program, if there were no concerns over renal failures or allergies.
[190]
[117] Professor Metz is a highly qualified and eminent haematologist. He is, amongst other things, a lifelong honorary consultant to the Department of Haematology in the Royal Melbourne Hospital and a consultant haematologist to Dorevitch Pathology. He had participated in the daily dosing of Warfarin during the period 1990-1997 and from 2000 to the time of the trial. In a report dated
[191]
14 February 2006, he addressed the question whether the defendant met the standard of care to be expected of the specialist Warfarin clinic by considering two separate time periods. He said from the period July 2001 to the end of December 2001, the degree of control was "well within the standard of care expected". He then considered the period of instability (details of which are in the table I have set out earlier in this judgment) and said:
[192]
"During this second period, [the defendant] adjusted the dose according to the INR, and measured the INR at frequent intervals (14 times). Faced with high INR's in the danger zone for bleeding on 2 occasions at a prescribed dose of less than 4 mg, it is understandable that the dose was increased cautiously during the period 13-25 February.
[193]
All this is the standard of care to be expected of a specialist warfarin clinic."
[194]
[118] He described the degree of difficulty in managing the plaintiff's Warfarin care from 3 January 2002 to 25 February 2002 as "extreme".
[195]
[119] In response to the question whether there was any lack of appropriate care on the part of the defendant in failing to refer the plaintiff to a specialist or suggesting to Dr Powell that a specialist referral be organised, Professor Metz said:
[196]
"With the INR at sub-therapeutic level, a specialist clinical haematologist would increase the dose of warfarin cautiously, and consider adding heparin to the therapy. The dose of warfarin was in fact increased by [the defendant] and subsequently by Dr Powell. The question of adding heparin is considered under Item (m).
[197]
In my opinion, there was no lack of appropriate care on the part of [the defendant]."
[198]
[120] In response to the question whether earlier intervention would have, on the balance of probabilities, prevented the stroke, Professor Metz said that earlier intervention would be the addition of Heparin therapy to the Warfarin during the period 16-25 February 2002. He said:
[199]
"In my opinion, this is probably the most critical issue. The control of warfarin therapy by pathology practices is limited to INR testing and warfarin dosing, and there is no mandate whereby they can directly add other drugs (other than vitamin K when there is serious over-coagulation). Heparin could have been added by Dr Powell on the recommendation of [the defendant], or directly by Dr Powell when he became aware of the persistently low INR's. There are, however, no published guidelines on the indications for heparin therapy when the INR falls during the control of warfarin therapy.
[200]
The addition of heparin may or may not have prevented [the plaintiff's] stroke, but given that there were no additional risk factors, such as atrial fibrillation, previous thromboembolism, or left ventricular dysfunction, coupled with the rarity of thromboembolism with the ATS valve even at relatively low INR values, and the exaggerated response to small doses of warfarin that was occurring at the time, it was reasonable not to add heparin at that time. I note that in relation to the issue of the low INR, Prof Fox in his report ... considers that an increase in the dose of warfarin would have been appropriate, or the use at that time of a heparin compound, with which I agree.
[201]
I believe that the action of [the defendant] in not recommending, and Dr Powell in not initiating heparin therapy, to be in accordance with reasonable medical practice."
[202]
[121] Professor Metz then went on to refer to the practical implications of adding Heparin, including complications arising from the risk of bleeding and other serious conditions.
[203]
[122] Further, Professor Metz agreed with Professor Fox's observation that it would have been reasonable practice for the pathology service to alert Dr Powell when the INR results first became erratic. Dr Metz's evidence, however, was clearly premised on the proposition that Dr Powell had been notified of the INR and Warfarin dose each time the INR was tested "and was aware of the erratic results".
[204]
[123] In a further report dated 18 August 2008, Professor Metz commented on Professor Fox's supplementary report. In respect of Professor Fox's suggestion that it would have been appropriate for the defendant to have entered into discussions with
[205]
Dr Powell, Professor Metz said that he was not aware of any guidelines as to when it was "appropriate" for the haematologist to enter into discussions with the general practitioner. Similarly, he was not aware of any guidelines relating to the obligation of a laboratory to recommend or advise on the administration of Clexane.
[206]
[124] The memorandum of a telephone conference with Professor Metz on 3 April 2009 records him expressing the view that none of the relevant guidelines at the time dealt with the management of patients on Warfarin who developed sub-therapeutic INR values. He agreed with a retrospective opinion expressed by Professor Fox that if Clexane had been administered in sufficient doses, it might have prevented the stroke. He emphasised, however, that this was purely a retrospective judgment, with knowledge that a stroke had been suffered.
[207]
[125] He went on to say that, in his opinion, it could have been dangerous in the plaintiff's case to administer Heparin at the same time as increasing the Warfarin dose, because there had been a tendency for the INR to increase to high levels on small increases in the dose of Warfarin. He said that to add another anti-coagulant could significantly increase the risk of bleeding, including bleeding of the brain, which could itself cause a stroke of greater severity than that which occurred (and was more likely to be fatal).
[208]
[126] Under cross-examination, Professor Metz conceded the desirability of earlier and more communication with the patient's general practitioner. He took issue with the notion, however, that the difficulty of the case would have led the haematologist to refer the patient to a cardiologist, saying that he was not aware that this was an obligation on a pathology practice. He thought the pathologist's brief was to dose patients in the Warfarin therapy. The question of referral to other specialist cardiologists would be one for the general practitioner.
[209]
[127] He accepted the proposition that, according to the knowledge of the time, the plaintiff, with her INR levels as they were from 16 February 2002, was at an increased risk of a thromboembolic event. Acknowledging that the haematologist was presented with a difficult management problem, the primary focus would have been on avoiding a thromboembolic event.
[210]
[128] Professor Metz also said, in response to questioning as to whether, by the third sub-therapeutic reading on 22 February 2002, he would have considered it appropriate to advise the plaintiff that she was in a risk situation, that:
[211]
"If the patient did not know what the INR was, yes, I think it's reasonable to inform them the INR is low and that there could be a problem. Absolutely."
[212]
[129] He subsequently reaffirmed that it would have been appropriate for a representative of the defendant to contact the plaintiff by the time of the second or third sub-therapeutic reading to inform her of the danger. He was questioned about the discussion he would have had with the plaintiff in those circumstances. He would have counselled her to take the medication as prescribed and not change her dietary habits. He also thought that one could suggest that she go and see her general practitioner, but would not bypass the referring doctor to refer the patient to a specialist.
[213]
[130] It became clear further in Professor Metz's cross-examination that his opinion with respect to Dr Powell's response in this case was based on an assumption that
[214]
Dr Powell had actually read the INR reports as they came in. (In fairness to
[215]
Dr Powell, it also needs to be recalled that the reports were being sent to him in the mail, and would have been some days out of date even by the time they reached his surgery.)
[216]
[131] In terms of a discussion he would have had with the plaintiff's GP as at
[217]
22 February 2002, Professor Metz would have told the GP that the Warfarin therapy was not under control, that the doses were being increased cautiously, and that the patient was at increased risk of thrombosis. He would then have left it up to the GP to decide whether to refer the patient to the cardiologist.
[218]
[132] In re-examination, Professor Metz was asked about the circumstance of a referral of the patient to their cardiologist, either by the GP or by the pathologist, and wondered in response what the cardiologist would do. He said that the cardiologist may feel that Heparin might be indicated at that time and that some cardiologists "would consider that possibility". He thought that this would really be the only point of referring the plaintiff to her cardiologist. The cardiologist would also have been aware of other risk factors and would have been in a better position to assess danger of thromboembolism in that circumstance.
[219]
[133] Professor Eikelboom is a specialist haematologist, and a principal of the Thrombosis Service in the McMaster Clinic at the Hamilton General Hospital in Ontario, Canada. In a report dated 9 December 2008, he said:
[220]
"Careful scrutiny of the INR records of [the plaintiff] reveals reasonable INR control between July 2001 and the end of the year (at least 2/3 of time in therapeutic range). From early January 2002 through to the time of discontinuation of warfarin management by [the defendant], INR control deteriorated and became rather erratic with wild fluctuations, both below and above the therapeutic range. Whilst the wild fluctuations in INR are not typical of day-to-day variability that is ordinarily expected during long term warfarin therapy, every clinic has a certain proportion of these extremely challenging cases. It should be emphasised that all of the dose adjustments by [the defendant], including the cautious increase in warfarin dose in the 2 weeks prior to stroke cannot be faulted."
[221]
[134] In relation the use of "bridging therapy", Professor Eikelboom said that it was important to clearly distinguish between patients who discontinue anti-coagulation for elective surgical procedures and those who were previously stable on long term anti-coagulation but develop erratic or sub-therapeutic INR control. He said that the majority of patients who develop a sub-therapeutic INR do not develop thromboembolic complications. He further said that he frequently encountered patients with poor INR control but "rarely bridged these patients with low molecular weight Heparin". His reasons for not doing this included a concern about the risk of bleeding when low molecular weight Heparin was added on top of Warfarin in patients who were temporarily sub-therapeutic. He said that the plaintiff's anti-coagulation "was finally beginning to stabilise immediately prior to her stroke and I would have been concerned about adding full dose anti-coagulation in a patient with a history of extreme INR fluctuations and an INR that was rising in response to apparently judicious dose management".
[222]
[135] He concluded that he was of the opinion that the decision by the defendant's physicians not to administer Clexane to the plaintiff in February 2002, in view of her history of INR instability, was entirely appropriate. He similarly thought that it would be neither usual clinical practice nor considered clinically appropriate to admit a patient with unstable INR to hospital for administration of intravenous Heparin.
[223]
[136] In a memorandum of a conference with him on 2 April 2009, it is recorded that Professor Eikelboom said that it would have been dangerous to add Heparin on top of the Warfarin, because it could have led to the plaintiff being over anti-coagulated and this would have led to a "very high risk of bleeding". He described the standard use of Clexane being when Warfarin was stopped temporarily to enable a surgical operation to take place, and said that "otherwise it is unwise and not indicated to use it". He spoke to the comparative risks of bleeding from over anti-coagulation with the risks of thromboembolism from under anti-coagulation while attempting to stabilise and slowly increase the patient's INR. The note records:
[224]
"He said that even if a patient was not taking warfarin, the risk of a thromboembolism would be about 20-30% per year, but when the patient's INR is around 2 or above, the risk of a thromboembolism is low, so it does not justify an additional anti-coagulant. Dr Eikelboom commented that very often one does not, or cannot, use bridging anti-coagulation even when stopping warfarin for surgery. The risk of a thromboembolism in those circumstances is maybe 1-2% per month.
[225]
He would be more worried about the risk of bleeding. The main concern is of bleeding into the brain, which is associated with a very high risk of death (about half of these patients die), whereas a thromboembolism is much less likely to cause death. That is not to say that a thromboembolic stroke is a benign condition; on the contrary, thromboembolic stroke is also an important cause of death and disability."
[226]
[137] Professor Eikelboom commented on the defendant's treatment in light of the low INR from 16 February 2002 onwards, noting the frequent testing and slow increase in dosage. He said that given her propensity for the INR to jump substantially with a low increase in Warfarin dose, it would have been dangerous to add another anti-coagulant to the regime while taking those steps.
[227]
"Dr Eikelboom was asked whether it would have been in accordance with ordinary accepted practices for [the defendant] to have discussed the problem with [the plaintiff's] general practitioner at an earlier time. His response that it was a fair criticism of [the defendant] that it did not do so. He thinks the appropriate course would have been to call the general practitioner and discuss it with him. However, he would not expect either the general practitioner or a cardiologist to suggest the use of clexane."
[228]
[139] He also thought that it would have been appropriate to discuss the problem directly with the patient, saying it was always appropriate to discuss poor INR control with a patient.
[229]
[140] Under cross-examination, Professor Eikelboom explained that the reference to "bridging" in his report was to the situation where one discontinues Warfarin and switches to low molecular weight Heparin. His reference to bridging did not include administering both Warfarin and low molecular weight Heparin at the same time. He agreed that there were situations where Warfarin was not having its desired effect when he would consider discontinuing Warfarin and switching to low molecular weight Heparin.
[230]
[141] Also under cross-examination, Professor Eikelboom confirmed that he would have thought it "proper practice" to discuss the erratic INR control with the plaintiff's general practitioner. He described the problem as being the sub-therapeutic and supratherapeutic INR. He would have told the general practitioner that the INR control was erratic and asked whether there was any explanation for this. Professor Eikelboom's discussion with the general practitioner would have been directed to finding an explanation to "understand a reason for the erratic control".
[231]
[142] Professor Eikelboom gave the following evidence:
[232]
"MR ELIADIS: I put to you that - I put to you that a reasonable haematologist, faced with Mrs Papa's situation in 2002, would have made contact with her and informed her of the risks she was exposed to of thromboembolic events; do you agree?-- I agree that the patient should be aware at every INR measurement, when the INR result is communicated to the patient, and together with that information comes a dose adjustment, the level is inappropriate, but no dose adjustment when it is in the therapeutic range, and I agree that, at that time, during that communication every second or third day, the patient should be reminded and informed that - that the level is not in the therapeutic range.
[233]
And do you also believe that the person should be made aware of what that means in layman's terms for their health?-- Yes, I agree. The patient should definitely be aware that high and low levels put her at risk of complication.
[234]
The - is it right to say that in circumstances such as this, where a plaintiff has to be on life long Warfarin therapy, and we have repeated sub-therapeutic readings, a problem has arisen, correct?-- I agree that this lady had a problem.
[235]
And-----?-- That there was a problem with this lady's INR control.
[236]
Yes, and that had to be addressed?-- That is correct.
[237]
What the Warfarin care specialist could do was add just the dosage, that was one thing it could do to address the issue, correct?-- That is correct.
[238]
The other thing that it could do was communicate with the patient's medical clinicians to address the issue, correct?-- I agree that the pathologist would have communicated with other physicians, but it was the pathologist's task the get the INR in the therapeutic range.
[239]
No, no, please just answer my question. I'm talking about communication. Now, I said to you that it is appropriate that one of the things to do is to dose according to what the judgment is of the specialist Warfarin care clinic. Apart from that, it's to make contact with and communicate with the patient's clinicians; do you agree?-- I agree."
[240]
[143] Professor Eikelboom disagreed with the proposition that the WCS should have advised the plaintiff, or her GP, that she should see her cardiologist, but did concede that it was not only always appropriate to discuss poor INR control with the patient, but it was also appropriate to discuss the ramifications of poor INR control with the patient.
[241]
[144] In re-examination, Professor Eikelboom gave the following further evidence about the information that he would expect to have been provided to a patient:
[242]
"All right. Thank you, doctor. Now, the other area you were pressed upon by Mr Eliadis was in terms of informing a patient of instability in INRs either above or below the target range and I think you agreed that a patient should be informed of the INR readings. Could you elaborate, doctor, on what you believe a patient should be informed of in that situation?-- Whenever a patient is treated with Warfarin it's critical that the patient is educated, so they come with a certain knowledge of Warfarin because critical to good INR control is close cooperation between a patient and the care provider. So the patient comes with the basic knowledge that Warfarin's a blood thinner, that higher levels cause bleeding, that low levels expose the patient to a risk of thromboembolism. When individual INR results become available, then the patient might be told, "Your INR's 1.8. That's too low. You're at increased risk of thrombosis. We should increase the dose.", and when a patient's INR is six one might say, "The level is too high. I'm very concerned about bleeding risk."
[243]
Right?-- If the patient's INR is consistently low, then the warning or the information would be elaborated. Where the patient is fluctuating unpredictably, then the concern - the focus would be on understanding the reason for that-----
[244]
Yes?-- -----because without understanding the reason it's very difficult to deal with the problem."
[245]
[145] Dr Hossack, a cardiologist, provided a report dated 19 August 2008. When asked his view as to the appropriateness or practice of prescribing Heparin or Clexane to the plaintiff in early 2002 in circumstances where her INR was grossly unstable, Dr Hossack referred to the American College of Cardiology/American Heart Association Guidelines for the Management of Patients with Valvular Heart Disease, and noted that there was no recommendation for the management of patients with sub-therapeutic INR values in patients with mechanical mitral valves. He said:
[246]
"This is indicative that there is no consensus as to how this situation should be management (sic). In the extreme situation where Warfarin has been discontinued in a patient with a mitral valve it is recommended that they be started on Heparin or Clexane while Warfarin therapy is initiated. However there are no guidelines for the situation of an individual with a mechanical mitral valve and a sub-therapeutic INR.
[247]
It would be my opinion that the recommendation by Dr Fox that Heparin or Clexane should have been administered in late February 2002 is a personal opinion not supported by clinical guidelines. I do not support the recommendation that Dr Fox proposed."
[248]
[146] A memorandum of a telephone conference with Dr Hossack on 3 April 2009 records him disagreeing with Dr Garrahy's statement that standard therapy would be to institute anti-coagulation with Heparin. Dr Hossack referred to the American College guidelines as both "comprehensive and recommendations that are standard of care". Relevantly, he said that the 1998 guidelines did not suggest the use of Heparin in the context of attempts to stabilise INR in Warfarin patients. He said that having regard to the plaintiff's recent history of high INR responses to small increases (or even decreases) in Warfarin doses, it would be inadvisable to introduce another anti-coagulant to her therapy, and would be very difficult to judge what levels to use. He thought the level of subcutaneous Clexane recommended by Dr Garrahy was very high, and pointed to the difficulties of judging appropriate levels of Warfarin to administer if one was also administering Heparin. He considered it an entirely reasonable practice, in a patient who had been established on Warfarin and whose INR became unstable, to make changes to the Warfarin dosage rather than to introduce another anti-coagulant. He thought that Dr Garrahy's statement appeared to be a personal opinion only, not backed up by any clinical guidelines. He repeated that it had never been standard therapy to institute anti-coagulation with Heparin in response to a sub-therapeutic INR in a patient with a mechanical mitral valve prosthesis undergoing Warfarin care. He said that the "therapy" recommended by Dr Garrahy was "very high risk", and risked serious over anti-coagulation when the patient was also taking Warfarin. He said: "It is a very dangerous approach".
[249]
[147] Under cross-examination, Dr Hossack repeated his concerns about administering unfractionated Heparin to a patient in the plaintiff's situation. Specifically in response to a suggestion that when one's INR is less than 2.5, adjusted doses of intravenous Heparin would provide adequate and not excessive anti-coagulation, Dr Hossack disagreed completely and said that his clinical experience had shown that some patients with those sorts of INR numbers could have significant bleeding complications with unfractionated Heparin. He drew the distinction between this sort of case and the use of Heparin in a perioperative situation and disputed that the two situations were analogous.
[250]
[148] Dr Hossack also questioned the effectiveness of the antidote Protamine in the event that the administration of unfractionated Heparin caused bleeding. He said that he was not certain why one would be giving intravenous Protamine, and the following passage of evidence ensued:
[251]
"Well, that's just there as an additional protection if you need it? - What for?
[252]
That is an antidote to neutralise unfractionated Heparin should any bleeding occur? - So what you're saying is you've got a person that's bleeding and you know that they've got a bleeding because they're paralysed down one side of their body and giving them Protamine is going to reverse their paralysis. Is that what you meant?
[253]
What I meant is that you've got an additional protection in the hospital setting to neutralise bleeding should it occur? - I'd suggest that giving Protamine after you've had an intracerebral haemorrhage is a bit like closing the barn door once the horses have bolted.
[254]
When a patient bleeds from anti-coagulant therapy I suggest to you that 80% of the time the bleeding is peripheral and not into the brain? - I would suggest that the majority of patients that have a bleeding into their brain die."
[255]
[149] When pressed again on the percentage of peripheral bleeding, Dr Hossack said that he thought the most serious complications of haemorrhage with anti-coagulation therapy were into the brain and a retroperitoneal haemorrhage.
[256]
[150] On another topic, Dr Hossack did confirm, however, that if the plaintiff had been sent to him for management at the time of her sub-therapeutic readings in February 2002, he would have tried to explain to her the risks of thromboembolism that she faced and the risks of bleeding which she faced if she was over anti-coagulated. Specifically in relation to the plaintiff's INR readings in late February, Dr Hossack said that if she had seen him on 23 February then, having regard to her previous INR's, he would have told her that there was a small increase in the risk of her having a stroke. In re-examination he said that he would have told her this even if he had previously been treating her and had explained it to her on previous occasions. He thought that it was helpful to reinforce the importance of certain types of target ranges.
[257]
[151] Numerous articles from learned medical journals were put before me. Some of these were relied on by various of the experts to support their opinions. Others were used as the basis for cross-examination. Some of the articles refer to research and learning after 2002. These articles assisted me in understanding the evidence of the experts and also, to some degree, support the evidence given as to the state of knowledge in the realm of anti-coagulant control as at 2002.
[258]
[152] It seems to me that the following propositions relevant to Warfarin control by specialist Warfarin care haematologists in 2002 can be drawn from the expert evidence:
[259]
(a) that the Warfarin dosage management process necessarily involved a balancing of the risk of under anti-coagulation and over anti-coagulation;
[260]
(b) that there was a known risk of thromboembolic event in the case of sub-therapeutic INR levels, and that this risk magnified when the INR was at or below 1.5;
[261]
(c) that there was a known risk of haemorrhagic event in the case of supra-therapeutic INR levels, and that this risk magnified very significantly when the INR was at or above 6.5;
[262]
(d) that in relative terms, the risk of an haemorrhagic event at INR 6.5 or higher was significantly greater than the risk of thromboembolic event at INR 1.5 or less;
[263]
(e) that the process of Warfarin dosage management with a view to keeping the INR within target range, and thereby minimising these risks, necessarily involved a significant component of clinical judgment on the part of the Warfarin care haematologist;
[264]
(f) that it was accepted practice at the time that the anti-coagulants Clexane or Heparin could be used on a patient with an artificial mitral valve as "bridging therapy" by way of a substitute for, or supplement to, Warfarin in a peri-operative setting;
[265]
(g) that neither the medical literature then available nor the standards of practice among Warfarin care haematologists at the time support a conclusion that it was appropriate for a Warfarin care haematologist, when dosing a patient with an artificial mitral valve who had a persistent sub-therapeutic INR, to supplement the prescription of Warfarin with either:
[266]
(ii) the administration of "stat" doses or Warfarin.
[267]
[153] In making these findings, I do not reject the evidence of either Professor Fox or Dr Davidson as to what their own particular practices were. But it was quite clear, in my view, on both the evidence as a whole and on their own evidence that there was not widespread support either amongst the haematologists or in the literature for the notions that a Warfarin care haematologist treating an artificial mitral valve patient with persistent sub-therapeutic INR ought to have resorted to the other anti-coagulants or "stat" doses. On the contrary, the general consensus amongst the experts was that the cautious approach of incremental increases in the Warfarin doses was appropriate.
[268]
[154] The conduct of the defendant in this case needs to be assessed not just in the context of the period in late February 2002, when the plaintiff was returning persistently low INR's. It was clearly appropriate for the haematologist also to have regard to the fact that in the preceeding month the plaintiff's INR had on two occasions "spiked" on the administration of average daily doses of 3.17mg of Warfarin to levels at which the risk of haemorrhagic event became significantly elevated (that being, in relative terms, the greater of the two risks in the balance). This was, as was conceded by a number of the experts, a difficult situation for the Warfarin care haematologist to manage. Reference by the haematologist to the immediate past history of "spiking" supported the cautious approach of incrementally increasing the dosages of Warfarin in an attempt to bring the plaintiff's INR above the sub-therapeutic level and into the target range.
[269]
[155] I do not regard Dr Garrahy's evidence as to the treatment he would have administered as particularly relevant to the present question. What treatment a cardiologist would have administered does not address the appropriate conduct of a Warfarin care haematologist.
[270]
[156] Accordingly, I would not be prepared to find that it has been established that the defendant failed to exercise and observe the standards of a reasonable Warfarin care haematologist in the management of the plaintiff's Warfarin dosage levels in the period 13 - 27 February 2002.
[271]
[157] The separate question on liability is, however, quite different. It goes to whether, according to the relevant professional and practicing standards at the time, the defendant, when presented with this artificial mitral valve patient with a recent history of INR instability and persistent sub-therapeutic INR's, ought to have given advice to the plaintiff, her GP or her cardiologist, and if so, what the content of that advice ought to have been and when it ought to have been given.
[272]
[158] It is quite clear, on the facts of this case, that the defendant in fact gave no advice to the plaintiff or her medical practitioners until, at best, Dr Rowbotham's call to
[273]
Dr Powell on 27 February 2002. The only information being provided to the plaintiff were her dosage instructions and the dates for her next tests. She was not routinely advised of her actual INR levels. I find that she was not so advised by the defendant's phone representative during January and February 2002.
[274]
[159] The information package initially provided to the plaintiff stated, inter alia:
[275]
"The target range is set either by your doctor according to your individual circumstances or by internationally recommended ranges for your condition. The target range defines acceptable results for you. Results that are too low present a risk of developing or extending an existing blood clot. Results that are too high present an increased risk of bleeding."
[276]
[160] This advice would only have had meaning to the plaintiff if she was informed of her INR and whether it was within, below, or above the target range. She was not given that information.
[277]
[161] It is also true that the plaintiff's INR results were being sent on in paper form by mail to her GP, Dr Powell. Even if he were reading them as they arrived, however, they would, by then, have been several days out of date. In that regard, I accept that the reference in the plaintiff's consultation with Dr Powell on 23 February 2002 to the plaintiff's INR having been unstable was not in respect of her then current sub-therapeutic INR levels but related to the history of "spiking" which had occurred in January 2002.
[278]
[162] From 16 February 2002, when the plaintiff was being tested every few days and was returning a persistently low INR, the defendant made no attempt to contact the plaintiff either to advise her of the fact that her INR's were at that level or of the risks which those levels posed for her health. Nor did the defendant take any steps to contact her GP, other than by mailing the lab results, to advise of the situation. This needs to be viewed in the context that Dr Rowbotham herself considered that she was facing a difficult situation in managing the plaintiff's INR's and was aware of the risks of under- and over-anticoagulation, and indeed justified her cautious dosage approach on the basis of managing those risks. Dr Rowbotham knew that the plaintiff was at risk of thromboembolism associated with her artificial mitral valve, but assessed the plaintiff as being at greater risk of bleeding if she were over anti-coagulated.
[279]
[163] Having regard to the situation of this particular plaintiff, with an artificial mitral valve which of itself dictated caution in respect of the risk of clotting and a recent history of INR instability, and also having regard particularly to the evidence of both Professor Metz and Professor Eikelboom as to the desirability, if not the necessity, to communicate with the patient, I consider that a reasonable Warfarin care haematologist in the position and having the knowledge of the defendant would have contacted the plaintiff:
[280]
(a) To advise of the unstable history of INR readings and of the persistent sub-therapeutic levels;
[281]
(b) To advise (or at least reaffirm) the risks associated with sub-therapeutic INR readings;
[282]
(c) To advise of the approach which was being adopted to incrementally increase dosage levels in an attempt to bring her INR back into range;
[283]
(d) To advise the plaintiff that she should consult her G P with respect to management of the risks associated with her sub-therapeutic INR levels.
[284]
[164] This contact and advice to the plaintiff should, in my view, have been given once it was apparent that the plaintiff's INR levels were consistently sub-therapeutic. That certainly would have been, at the latest, at the time of the INR reading of 1.5 on
[285]
[165] Similarly, in my view, a reasonable Warfarin care haematologist faced with these circumstances would have contacted the plaintiff's general practitioner upon, at the latest, receipt of the test results on 22 February 2002. The risk of a thromboembolic event occurring in a mitral valve patient required, in my view, that the Warfarin care provider not unilaterally seek to manage the under anti-coagulation with the approach of incrementally increasing dosages but ensure that the plaintiff's general practitioner, as her primary medical care provider, was alert to the plaintiff's situation and the risks which were then in play. This required contact with the general practitioner:
[286]
(a) To ensure that the general practitioner was aware of the plaintiff's persistent sub-therapeutic INRs;
[287]
(b) To advise of the dosage approach being adopted;
[288]
(c) To reaffirm the existence of the risks associated with the sub-therapeutic INR; and
[289]
(d) To recommend that the GP undertake or investigate management of the risks associated with the plaintiff's sub-therapeutic INR levels.
[290]
[166] I do not, however, consider that it would have been either appropriate or reasonable for the Warfarin care haematologist to make contact directly with the plaintiff's cardiologist. Leaving aside any questions as to the protocol of contact between medical specialists, the appropriate chain of contact and advice was from the haematologist to the general practitioner, as the plaintiff's primary care provider. It was not for the Warfarin care haematologist to instigate contact with the cardiologist. That was a matter for the general practitioner, after receiving the advice from the haematologist, to which I have already referred.
[291]
[167] Whilst it was not, for the reasons I have given above, appropriate for the defendant itself to instigate alternative treatment with Clexane or Heparin, it seems to me, in the circumstances of this case, that when advising the GP to undertake or investigate management of the risks then faced by the plaintiff, it would have been reasonably appropriate for the defendant at least to raise the prospect of the GP investigating alternative or supplementary forms of anti-coagulation and also to raise the prospect of this needing to be done in consultation with the plaintiff's cardiologist.
[292]
[168] In reaching this conclusion, I draw not merely on the consistent evidence among the experts as to the desirability of appropriate communication between the Warfarin care haematologist and the patient and the patient's GP, but also Dr Davidson's evidence to the effect that not all GP's are up to date in managing complex anti-coagulation problems and would probably need some guidance. A fortiori in a case such as the present, which Dr Rowbotham described as having presented her with a "difficult management problem" because of the need to balance the risks of a thromboembolic event and an haemorrhagic event, and which involved a patient with an artificial mitral valve who in the weeks immediately preceding the persistent sub-therapeutic levels had demonstrated INR instability. In my view, a reasonable Warfarin care provider would have given the kind of advice and guidance to which I referred in para [167], as part of the guidance expected of and from a specialist Warfarin care service. The giving of this advice and guidance did not involve questions of clinical judgment. By not communicating this advice to the plaintiff and this advice and guidance to her GP, the defendant failed to meet the standard of care required of a reasonable Warfarin care haematologist.
[293]
[169] The question then arises as to what is likely to have happened if the defendant had given the advice to the plaintiff and her general practitioner which I consider it should have but did not. Specific questions addressed to Dr Powell concerned his response if he had been told by the defendant that the plaintiff should consult with her cardiologist or that he should administer Clexane to the plaintiff. His response is that he would have followed the advice given by the defendant in that regard. Considering Dr Powell's evidence as a whole, however, I also consider it more likely than not that if he had, by no later than 22 February 2002 received the advice and recommendations to which I have just referred, he would have referred the plaintiff to her cardiologist, Dr Garrahy. The defendant points to the fact that when the plaintiff was discharged by the defendant into Dr Powell's care and saw him on 28 February 2002, his only response at that time was to continue with an incremental increase in her Warfarin dose and refer her to QML for ongoing Warfarin care. He did not, at that time, mention the possibility of referring her to her cardiologist. It is not, however, at all clear on the evidence that Dr Powell, when he saw the plaintiff on 28 February 2002, had a full picture of the extent of the plaintiff's sub-therapeutic readings. He had the current reading of 1.7 from the defendant. Had he been made aware at an earlier stage, however, of the persistent sub-therapeutic levels being returned by the plaintiff and been given the advice which I consider he should have been given, it is, I think, more likely than not that he would have instigated steps with the appropriate specialist with a view to further managing the risks associated with those sub-therapeutic INR levels. The appropriate specialist for such a referral would have been the plaintiff's cardiologist, and I consider it more likely than not that Dr Powell would have arranged for such a referral. The plaintiff would certainly have accepted and acted on that referral.
[294]
[170] It is also clear from Dr Garrahy's evidence that if the plaintiff had been referred to him at that time (and I accept that he would have been available to attend upon her virtually immediately), then it is more likely than not that Dr Garrahy would have instituted the treatment regime he described in his evidence. The fact that
[295]
Dr Hossack disagreed with Dr Garrahy's proposed treatment regime is really not to the point. The question for present purposes is for me to make an assessment as to what course of events I consider would likely have followed if the defendant and her GP had given the advice which I consider it should have. Similarly, it is neither necessary nor appropriate for me to make a determination as to whether the response proposed by Dr Garrahy would have been that of a reasonable cardiologist in the circumstances. The fact is that if the plaintiff had been referred back to him, that is the treatment he would have put in place.
[296]
[171] I find that if Dr Garrahy had instituted the therapeutic procedures he described in his evidence on, or shortly after, 22 February 2002 then it is more likely than not that the risk of the plaintiff suffering a thromboembolic incident would have been ameliorated, and accordingly it is more likely than not that she would not have suffered the stroke she did on 1 March 2002. True it is that Dr Garrahy's proposed treatment carried with it an increase (perhaps a significant increase) in the risk of the plaintiff suffering an haemorrhagic event. But that was a risk to be managed by him as her treating cardiologist. His management of that risk is not a matter for present adjudication.
[297]
[172] In all the circumstances, then, I am satisfied on the balance of probabilities that the defendant's failure to give advice to the plaintiff and her general practitioner by about 22 February 2002 in respect of the matters outlined above was a breach of the defendant's duty of care to the plaintiff which was causative of her suffering the stroke on 1 March 2002. Accordingly, the plaintiff has proved her case of liability against the defendant.
[298]
[173] Both the plaintiff and her husband, Mr Carlo Papa, gave evidence before me. My assessment is that they were both truthful and credible witnesses.
[299]
[174] The plaintiff was born in Liverpool, England on 28 May 1956. She completed
[300]
Year 12 at Burwood Girls High School, Sydney, in 1973. In 1974, she commenced a science degree at the University of Sydney. In 1975, after completing the first year of that course, she commenced the first year of an arts degree. In 1976, she worked for a period of about six months as an assistant nurse at a psychiatric hospital in Ryde and then for a period of about two years she worked as a shop assistant. In 1980, she started working for the New South Wales Housing Commission. She married Mr Papa on 27 September 1980.
[301]
[175] The plaintiff and Mr Papa have two sons, born in 1981 and 1983. The family moved to Queensland in April 1985. In 1986, the plaintiff successfully completed the Queensland Public Service Sector examination and was employed in the Department of Education. From about March 1986 until March 1990 she was employed as an assistant finance officer in the "Planning and Special Programs" section on a full-time basis.
[302]
[176] The plaintiff sat the Commonwealth Public Service examination and in March 1990 was offered employment in the Department of Social Security as a field officer. She worked in that capacity from 1990 until 1992 and in 1993 was promoted to team leader. She continued in that role until 1995, when she was moved to work in the Brisbane City area as an assistant area review coordinator. At the end of 1995, she was promoted to area coordinator. She worked in that capacity until 1998, when she was seconded to the policy area. In 1999 she returned to her old workplace as a team leader for student review.
[303]
[177] At the time of suffering her stroke on 1 March 2002, the plaintiff was employed on a full-time basis in the Commonwealth Public Service as a clerical officer at Level C3.3. There is no issue about the rates of income she would have earned in that position since that time. She was retired from the Commonwealth Public Service on the grounds of invalidity from 21 November 2002.
[304]
[178] At the time she suffered her stroke, her husband was employed as a full-time taxi driver/operator.
[305]
[179] The plaintiff has not returned to remunerative employment. At the time of trial she was studying a science degree at the University of Southern Queensland as an external student. She expected to finish her undergraduate degree at the end of 2010 and aimed to qualify as a registered psychologist at the completion of her studies in mid-2011. By that time, the plaintiff will be 56 years old and will have been out of the workforce for more than 9 years. She said in evidence that she hoped to work as a counsellor "maybe [on a] part-time basis".
[306]
[180] It is quite clear, on the evidence, that the stroke has caused the plaintiff permanent and debilitating damage. She presented to the Princess Alexandra Hospital on
[307]
1 March 2002 having suffered a large right middle cerebral artery territory embolic infarction. Her initial symptoms included:
[308]
- left VII cranial nerve upper motor neurone lesion;
[309]
[181] The plaintiff required hospitalisation and rehabilitation treatment as both an inpatient and outpatient. Her periods of inpatient treatment were:[10]
[310]
(a) in the Princess Alexandra Hospital between 1 March - 12 March 2002 and 3 June - 21 June 2002;
[311]
(b) The Mater Private Rehabilitation Unit from 12 March - 3 June 2002; and
[312]
(c) Mt Olivet Hospital between 24 June - 2 August 2002, 4 March - 19 March 2003, and 14 July - 25 July 2003.
[313]
[182] Her inpatient rehabilitation treatment has included botulinum toxin treatment for spasticity; physiotherapy for mobilisation and gait retraining; bed mobility and transfers; cognitive assessments; occupational therapy for serial casting to her left arm; self-care retraining, lessons in activities of daily life and dressing techniques. She was also required to take medication, including analgesia and anti-depressants. She required surgery to her left leg to release tendons and increase her mobility.
[314]
[183] Her outpatient treatment included the botulinum toxin treatment, physiotherapy, hydrotherapy, oral mediation, remedial driving lessons (with a view to assisting her to return to driving for independence) and a home exercise/strengthening program.
[315]
[184] It is not in issue that the plaintiff has required treatment from a variety of medical practitioners, including neurosurgeons, neurologists, cardiologists, physicians and orthopaedic surgeons.
[316]
[185] At the time of trial she was continuing to undergo physiotherapy and exercise physiology on a weekly basis, hydrotherapy sessions on a weekly basis, receiving input from a dietician, visiting an acupuncturist, attending on a psychologist and being treated by a naturopath. She will also require measures such as the botulinum toxin treatment for the rest of her life.
[317]
[186] The plaintiff has been left with severe spasticity affecting the left side of her body. She is able to mobilise with the aid of a walking stick. Her left arm is not functional, and her left leg is severely impaired. Her gait speed is slow and unsteady. She has cognitive difficulties, subtle concentration difficulties, and disturbance of the ability to carry out skilled voluntary movements. Her emotions and mood are labile and at times she suffers from depression.
[318]
[187] The plaintiff continues to suffer from the following incapacities:
[319]
- pins and needles in the left lower limb and left hand;
[320]
- a reduced capacity to engage in daily living activities;
[321]
- surgical scarring from the tendon release surgery.
[322]
[188] The plaintiff described to me the affects on her life and lifestyle of having suffered the stroke, and the depression she suffered as a consequence of the hospitalisation. She said she "just felt hopeless and had just been in hospital for so long and ... going through the rehab process was quite traumatic really". She described herself as going from someone who was very independent to not even being able to take herself to the toilet. That being said, the plaintiff, to her credit, has clearly overcome the psychological difficulties, undoubtedly assisted by the support of her family. Her husband is clearly devoted to her. He described their life together before and after the stroke. He described their relationship as a loving one - "we really enjoy each other's company and we love each other and we're very close". He said that this was not only still the case, but it was probably more so since she had suffered the stroke. I am quite satisfied that Mr Papa's support has been a significant factor in assisting the plaintiff's rehabilitation.
[323]
[189] Both the plaintiff and her husband also described the deleterious impact which the plaintiff's injuries have had on her capacity to socialise and enjoy time with family and friends.
[324]
[190] Having regard to the nature of the injuries suffered and their sequelae, the plaintiff's age and the affect that has been wrought on her enjoyment of the amenities of life, I assess the plaintiff's general damages at $150,000.00.[11]
[325]
[191] Given the plaintiff's age and the enduring affect of her injuries, I will allow interest at 2 per cent on 50 per cent of those damages, yielding $12,750.00.
[326]
[192] As at the trial, the undisputed calculation of the pay which the plaintiff would have earned but for suffering the stroke was $225,155.00. Allowing a further 68 weeks at a net weekly amount of $880.00 yields a further $59,840.00. That brings the total past economic loss to $284,995.00.
[327]
[193] Interest should be allowed on that sum at 5 per cent from 22 November 2002, when the plaintiff was retired from the public service, yielding $111,575.00.
[328]
[194] The defendant urged that I impose a discount of 10 per cent for contingencies in respect of this past economic loss. I am disinclined to do so. No good reason was advanced for the imposition of such a discount. The plaintiff was in secure employment. Not all contingencies are adverse to a plaintiff.[12] Whilst the plaintiff might have been otherwise adversely affected in her employment by her prior heart condition, her employment history shows the prospect that she would have been promoted further in the interim. Balancing these considerations leads me to reject the submission that there should be a discount in respect of past economic loss.
[329]
[195] There is no issue that the plaintiff should be compensated for lost past superannuation benefits. I will make the conventional allowance of 9 per cent of the sum assessed for past economic loss, yielding $25,650.00.
[330]
[196] The plaintiff's claim for future economic loss is in the order of $330,000.00. The claim is calculated on the basis of the whole of her net weekly income at the time of suffering the stroke until the time she reaches 65, less a discount of 20 per cent for contingencies and residual earning capacity. The plaintiff's submission in this regard relied heavily on a report by the occupational therapist, Ms Stephenson, dated 3 March 2009, in which Ms Stephenson (partly reporting matters that had been told to her by the plaintiff) said:
[331]
"Mrs Papa commenced studying a bachelor of science with a psychology major in 2005, through USQ. She would like to work in the field of Rehabilitation Psychology for persons with Acquired Brain Injury. She is currently in her fourth year studying part-time, and has two more years to finish her bachelor degree. Mrs Papa is now 52 years of age. If she is successful in completing her studies, her age and severe disability would be major barriers to obtaining employment. She is concerned that when she graduates she will be aged 55 and of pre-retirement age. Applied psychology is a highly competitive fields with many post-graduates being unemployed. She may find it difficult to enter such a highly competitive field with the further disadvantage of age and disability.
[332]
In the future it would be advantageous for her to consider working from home or engaging in part-time work, where she has the flexibility to rest throughout the day, or carry out work task for only a few hours at a time. She is suited to sedentary work, and could cope in a part counselling role, 10-20 hours per week."
[333]
[197] The plaintiff submitted that, despite her best efforts, the prospects of her earning some income in the future would best be described as speculative. Hence the allowance of a 20 per cent discount in her calculation for contingencies and residual earning capacity.
[334]
[198] The defendant, however, pointed to medical reports which indicated that the plaintiff's studies were progressing well, and also a comment by Ms Stephenson that once the plaintiff had completed her studies and become a fully qualified psychologist, she might be able to work 10-20 hours per week as a disability counsellor. This capacity to work was confirmed by the plaintiff in her evidence, although I frankly think she was being a little optimistic in that regard.
[335]
[199] The defendant submitted that whilst it was not clear what earnings the plaintiff might obtain as a disability counsellor, "one would expect that it would certainly be no less than her earnings in her previous position while she was working part-time from October to December 2001". This submission seems to me, with respect, to be speculative, at best.
[336]
[200] There are other factors to consider, however, not the least of which is that, even on her own evidence, the plaintiff would not be able to commence in this proposed employment unless and until she completes her qualifications. That was not anticipated to occur before mid-2011. By that time she would, assuming a retiring age of 65, have some 10 years left to her in the workforce.
[337]
[201] It is also the case that the plaintiff's disabilities, including to some degree her pre-existing cardiac condition, call for significant allowance to be made to accommodate for vicissitudes of life.
[338]
[202] Having regard to all these matters, it seems to me that it is appropriate simply to calculate the quantum to be awarded for the plaintiff's loss of earning capacity by allowing her a loss of $880 net per week discounted at 5 % for 10 years into the future, and then discounting the result by 30 %. That level of discount, it seems to me, appropriately reflects the uncertainties associated with her future employment and the vicissitudes of life. On that basis, the award for future economic loss is $254,408.
[339]
[203] The plaintiff has claimed Wilson v McLeay damages in the sum of $10,369 for attendances by Mr Papa on the plaintiff while the plaintiff was a hospital inpatient in 2002 and 2003. Details of the days and hours claimed are contained in a schedule in evidence before me. For most of the attendances, the amount claimed is based on Mr Papa's attendance for three hours per day.
[340]
[204] The defendant submits that this claim is excessive and that the time that Mr Papa spent at hospitals while the plaintiff was an inpatient was spent substantially in undertaking tasks which would ordinarily be undertaken by hospital staff. The defendant pointed to the fact that the rationale for damages under Wilson v McLeay is that, where there is medical evidence that has indicated the presence of a family member at the hospital has had a definite therapeutic value, some sum will be allowed to reflect this. Such damages are not, however, designed to compensate a plaintiff for the provision by family members of services which do not fill a relevant "need" in view of the fact that the plaintiff had full-time hospitalisation. In other words, these damages do not compensate for a family member undertaking tasks that would otherwise be undertaken by hospital staff.[13]
[341]
[205] There was no dispute before me as to the number of hours Mr Papa had attended at the hospitals, nor was there any issue as to the rate at which these damages were being claimed. The sole point was as to whether all of those hours were compensable under this head of damage. It seems clear on Mr Papa's own evidence that, while much of the time during his attendances was devoted to providing his wife with company (and I accept that this had a demonstrable therapeutic benefit for her recovery), some component of the time he spent was in attending to jobs which otherwise would have been undertaken by hospital staff.
[342]
[206] In the circumstances, I will allow 75 per cent of the time claimed under this head as recoverable Wilson v McLeay damages, and (after rounding) will award the plaintiff $7,500. Interest will be allowed on that sum at 2 % for 8.5 years, yielding $1,275.
[343]
[207] The plaintiff has been left significantly debilitated by the effects of the stroke. She clearly required, and will continue to require, care and assistance in her daily activities. Both the plaintiff and her husband gave evidence before me in respect of the different tasks in which that assistance has been and will continue to be required. In that respect, Mr Papa has been the primary care provider. The assistance ranges from areas including personal care (bathing, dressing, etc) to domestic duties (cleaning, cooking, etc).
[344]
[208] Apart from the evidence of the plaintiff and her husband, the plaintiff relied on a number of reports obtained from Ms Lesley Stephenson, occupational therapist. Ms Stephenson's reports are of assistance because they contain the reporting by the plaintiff and her husband of the time actually spent by Mr Papa in providing assistance to his wife. There is no reason to doubt the accuracy of those estimates, which were largely confirmed by the plaintiff and Mr Papa in evidence before me.
[345]
[209] The defendant relied on reports by Ms Gail Smith, occupational therapist. Ms Smith undertook a review of the capacity of the plaintiff to perform personal activities of daily living and to perform domestic tasks. It is sufficient for present purposes to note that Ms Smith reported that, although the plaintiff had resumed a general level of independence with personal care, she still relied on her husband to some degree for personal assistance in bathing and dressing, and that it was unlikely that her independence in respect of those matters would change in the future. Similarly, with respect to domestic tasks, Ms Smith noted the plaintiff's limitations in respect of matters such as meal preparation and cleaning, and also observed that her independent functioning in respect of these domestic was unlikely to change in the future.
[346]
[210] The differences between the plaintiff and the defendant with respect to appropriate awards of damages to be made under this head related to two matters:
[347]
(a) The defendant contended that the number of hours claimed by the plaintiff was overstated, principally because much of the work for which claim is made was not for the plaintiff's benefit solely but for the benefit of her family;
[348]
(b) The defendant contended that the rate sought for future care and assistance was too high.
[349]
[211] As to the first of these matters, it is important to recall that Griffiths v Kerkemeyer damages relate to the servicing of the plaintiff's needs as a consequence of the injuries suffered. In CSR Limited v Eddy[14] it was said:[15]
[350]
"In short, as the appellants submitted, Griffiths v Kerkemeyer damages are awarded to plaintiffs to compensate them for the cost (whether actually incurred or not) of services rendered to them because of their incapacity to render them to themselves, not to compensate them for the cost of services which because of their incapacity they cannot render to others. In each instance there may be a "need" for services, but it is a different kind of need, and the recipient of the services is different."
[351]
[212] In criticising the plaintiff's claim in this regard, the defendant pointed to matters particularly encompassed within the domestic duties component, which were for the benefit not only of the plaintiff but also for her husband and two sons, i.e. the whole household. It was submitted that "a large proportion" of the domestic care was not for services to the plaintiff, but for services to the household in which she lives. It was submitted that, at most, it might be said that half of the items claimed as domestic services were for services to the plaintiff, which would reduce the claim to about 14 hours per week. That 14 hour per week figure happens to coincide with the estimate made by Ms Smith of the number of hours of assistance which the plaintiff did and will require for personal care and domestic assistance.
[352]
[213] I think that there is some degree of inadvertent overstatement in the figures advanced on behalf of the plaintiff. The overstatement is inadvertent because there would, inevitably, be matters encompassed within the claim for services to the plaintiff which overlap with services provided for the benefit of the family as a whole. I do not, however, consider that the degree of discounting for this aspect should be as severe as contended for by the defendant. The fact that the family also benefits from services which are provided to meet the plaintiff's needs does not in any way detract from the fact that the plaintiff's need exists. It would be quite artificial, for example, to suggest that Mr Papa should cook two meals - one for the plaintiff, for which his time would be compensable, and another meal for him and the family.
[353]
[214] The hourly rate at which these damages are calculated is not in issue.
[354]
[215] The amount claimed by the plaintiff for past care (up to 20 April 2009) amounted to $282,034.24. Updated to the present, the claim, on the basis of the plaintiff's calculations, would increase by some $55,000, yielding, in round figures, a claim for $337,000. I think the appropriate approach in the circumstances, is to reduce that by 20 per cent to account for those components of the care claimed which were not strictly solely for service of the plaintiff's needs. That yields an allowance for past gratuitous care of $270,000. I will allow interest on that at 2% since the date of the stroke, being an allowance of $45,900.
[355]
[216] In respect of future care, the issue between the parties goes particularly to the rate at which these damages are to be calculated. The plaintiff seeks a future allowance of 10.66 hours per week for personal care, at $35.85 per hour (being the prescribed rate for a personal care attendant, level II). The claim for domestic duties is for 29 hours per week at a rate of $34.10 per hour (being a commercial rate for home care).
[356]
[217] The defendant contended that these commercial, or "agency", rates are not appropriate in the circumstances. It was submitted that the appropriate rate is that at which individual personal carers would be paid if they were employed directly by the plaintiff. It was submitted that the plaintiff has the personality and cognitive abilities to both employ personal and domestic assistance for herself, and if she were to do so, then a personal carer would be paid about $22.90 per hour and a domestic assistant between $17.00 and $25.00 an hour. Under cross-examination, Ms Stephenson agreed with those rates, and also confirmed that, in her assessment, the plaintiff is capable of employing appropriate carers and that she had no need for an agency on a long-term basis, thus allowing her to avoid the substantial agency fees charged.
[357]
[218] The elements of the future care claim are for personal services and, separately, for the provision of domestic services. I accept the estimate that the plaintiff requires, and will continue to require, something in the order of 10 hours per week of personal assistance. Having regard to the plaintiff's age, and the inevitable fact that as she grows older the degree of domestic assistance which will be required will increase, I would allow her 25 hours of domestic assistance a week. That is a total allowance per week of 35 hours. Having regard to the variation of the rates, but also giving consideration to the fact that while the plaintiff is presently able to source appropriate carers without agency assistance that situation may well change in the future, I am inclined to fix a rate of $25.00 per hour as representative of the cost of the provision of that care. The plaintiff, now aged 54, has a life expectancy of some 30 years. A loss of $25.00 per hour for 35 hours per week over 35 years, calculated on the 5% tables, yields $766,500.00. I would discount that allowance further by 15% to allow for the usual vicissitudes, as well as the contingencies arising from the plaintiff's condition. The allowance for future gratuitous care will be $651,525.00.
[358]
[219] The plaintiff made a claim for $46,603.20 for the cost of travelling in the future to rehabilitation specialists, physiotherapists and other medical practitioners. Counsel for the plaintiff, in my view, appropriately conceded that it would be appropriate to make a reduction to that claim of about 20% to account for the possibility that not all therapies will be continued for the rest of the plaintiff's life at the same frequency and intensity. I will allow the sum of $37,000.00 under this head.
[359]
[220] The plaintiff claimed some $242,561.73 for future medical and health treatment, and conceded a discount of 15% for the usual contingencies.
[360]
[221] The schedule of future health requirements claimed include both future botox treatment and weekly physiotherapy. Counsel for the defendant conceded that the claim for future botox is reasonable, but that the claim for weekly physiotherapy on top of the botox was excessive. The defendant pointed to evidence from the plaintiff's physiotherapist to the effect that the only reason she might need weekly physiotherapy is if she did not undertake her home stretching program of 10-15 minutes twice per day. If she did that stretching, it would be unnecessary for her to see the physiotherapist weekly. There remains, however, an ongoing need for the plaintiff to have four or five physiotherapy treatments per year.
[361]
[222] Claim was also made for attendances for "psychotherapy", which actually appears to be a claim for diet management. I agree with the defendant's submission that this claim, as a claim for the rest of the plaintiff's life, is inappropriate.
[362]
[223] Removal of these items, but making an allowance for four or five physiotherapy visits per year, reduces the plaintiff's claim to (in round figures) $200,000.00. Reducing that by the 15% for contingencies properly conceded by the plaintiff yields an allowance under this head of $170,000.00.
[363]
[224] The plaintiff makes a claim for some $82,250.00 for adaptive equipment which she will require in the future. Details of that are contained at length in Ms Stephenson's report. The defendant disputed only several of the items. It submitted that it is unnecessary for the plaintiff to have both an electric scooter and a powered wheelchair. On the evidence of the plaintiff's mobility, I agree, and would disallow the electric wheelchair.
[364]
[225] Despite some opposition by the defendant, I am, however, inclined to make allowance for the plaintiff to have a bath lifter. The fact that she is presently capable of having a shower ought not mean that she is disentitled from the obvious benefits to her of having a bath. The amounts claimed by the plaintiff under this head will therefore be reduced by $29,573.16 (being the claimed cost of the powered wheelchair, its recurring costs and maintenance). The amount I will therefore allow for future equipment is thus $52,675.00.
[365]
[226] After allowing for an arithmetical error in the plaintiff's calculations, the undisputed quantum of the plaintiff's past special damages is $117,169.00. Some $22,500.00 of that was paid for by the plaintiff. Interest on that amount at 5% since the date of the stroke will be $9,560.00.
[366]
[227] My assessment of the damages recoverable by the plaintiff is, therefore, summarised as follows:
[367]
[228] I do not propose applying any further discounting to these damages. In the discounts that I have already applied for contingencies and vicissitudes, I have necessarily taken account of the possibility that the plaintiff may have suffered, or will in the future suffer, some damage as a consequence of her pre-existing heart condition. The defendant did not press for there to be any such further discounting.
[368]
[229] Accordingly, there will be the following orders:
[369]
1. There will be judgment for the plaintiff against the defendant in the sum of $2,201,982.00.
[370]
[1] The alternative basis on which the plaintiff's case was presented, i.e. for having suffered a loss of chance or opportunity of receiving reasonable and appropriate treatment which would have eliminated or reduced the prospects of suffering a stroke is clearly no longer maintainable in light of the judgment of the High Court in Tabet v Gett[2010] HCA 12. That case was argued in the High Court while judgment in this matter was reserved and the parties requested that I refrain from delivering judgment in this matter until the decision in the High Court was known and the parties had the opportunity to make further submissions.
[10] As pleaded in para 23 of the Statement of Claim
[377]
[11] I note that, independent of my assessment, both Counsel for the plaintiff and Counsel for the defendant submitted that this was an appropriate quantification.