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Courts struggle on causation tests in some malpractice cases

Decision tackles delayed diagnosis allegations
|Written By Anita Balakrishnan
Courts struggle on causation tests in some malpractice cases
Paul Harte says a recent case shows how there is a ‘real challenge in establishing causation in a medical negligence case when there are both negligent and non-negligent causes.’

A recent decision from the Court of Appeal for Ontario highlights uncertainty in the law surrounding causation in medical malpractice cases of delayed diagnosis allegations, according to a lawyer that worked on the case.

The April 25 decision, White v. St. Joseph's Hospital (Hamilton), 2019 ONCA 312, upheld the lower court’s decision, but it also included obiter remarks, said Paul Harte, principal at Harte Law in Richmond Hill, Ont., who represented the appellants. Harte says it’s the latest in a string of cases where a plaintiff failed in a delayed infection case.

“One of the things that this case demonstrates is the real challenge in establishing causation in a medical negligence case when there are both negligent and non-negligent causes,” says Harte. “In this case, it was alleged that there was a delay in treatment, but of course there was an underlying illness to begin with. And sorting out what materially contributes to a plaintiff’s loss can sometimes be very challenging as this case demonstrates.”

The case revolved around Paul White, who suffered a complication — a “pinhole” bowel leak — that was not detected for some time after a routine surgery.

A nurse found that White had mottled limbs when she went to give him a morning bath, so she called a doctor because of signs of septic shock.

White said that he experienced “abnormal changes” starting the night before his mottled limbs were discovered, including pain, low blood pressure and insufficient urine output, but the lower court judge found that the nurse had met the standard of care in response to those changes.

When White was resuscitated, he was supposed to be given a dose of a medicine called Pip-Taz. There was a dispute about whether the medical record showed the medicine had been given correctly, but the trial judge concluded that White had not missed a dose. A few days later, a blood culture showed that White should get antibiotics, rather than Pip-Taz.

White ultimately had a longer hospital stay, including a stay in the Intensive Care Unit, and remedial surgery, due to the septic shock as well as an unrelated bowel perforation that developed later. One expert witness said that “most of Mr. White's outcome was unavoidable.”

The judges dismissed White’s appeal and said the respondents were entitled to $20,000 in costs, upholding the lower court’s findings that White had not established that the alleged negligence caused or exacerbated his injuries.

“In an action for delayed medical diagnosis and treatment, a plaintiff must establish that the delay caused or contributed to the unfavourable outcome,” wrote Justice Peter Lauwers, with justices William Hourigan and Gladys Pardu concurring. “Appellants’ counsel is correct that there was evidence that delay in treatment can have adverse consequences on a patient’s outcome. What is missing here is an actual link between the delay in diagnosis and treatment, and Mr. White’s injuries.”

Anna Marrison, a partner at Borden Ladner Gervais LLP, said White v. St. Joseph's Hospital (Hamilton), 2019 ONCA 312 is important in that it addresses issues raised by two prior decisions: Clements v. Clements, 2012 SCC 32 (CanLII) and Sacks v. Ross, 2017 ONCA 773 (CanLII). Marrison and fellow BLG lawyer John McIntyre said in an email statement that White v. St. Joseph's Hospital (Hamilton), 2019 ONCA 312 affirms Clements as the law.

In the Clements case, the Supreme Court said that “the test for showing causation is the ‘but for’ test. The plaintiff must show on a balance of probabilities that ‘but for’ the defendant’s negligent act, the injury would not have occurred.”

The Ontario Trial Lawyers Association had previously said the Sacks decision shows that “courts are struggling to understand and apply the causation instructions from Clements.”

“This is a potentially complicated area of the law. Much judicial ink has been spilled on the topic,” Harte says.

Brooke MacKenzie, a co-founder of MacKenzie Barristers, who acted on Sacks v. Ross, says trial judges and the Ontario Court of Appeal have yet to reach a consensus on how causation questions should be framed and that it would be useful if the Court of Appeal or Supreme Court provided some clarity on this issue in the future.

“The court in this case applied the appropriate test for causation, asking but for the alleged delay in treatment, would the plaintiff have suffered the unfavourable outcome?” she said in an email. “Despite the Supreme Court’s clear message in Clements, there remains some confusion as to precisely how the ‘but for’ test is applied. . . . This issue continues to be hotly contested in jury trials in particular.”

Rikin Morzaria, a partner with McLeish Orlando LLP, says causation issues come up frequently and that, in issues of delayed diagnosis with multiple actors that could have contributed to the delay, he approaches the allegations with trepidation.

“First you figure out, as a jury or trier of fact, did the delay in diagnosis or treatment cause injury to the plaintiff? And then second, if the answer to the first question is yes, did the particular defendant conduct cause or contribute to the delay?” says Morzaria. “In this case, I think the distinguishing feature was they never got to that step that there was agreement that the delay caused any injury.” 

  • Dental Malpractice linked to seminars

    Michael Zuk DDS
    Many dental patients with concerns about over-treatment find it difficult to find lawyers who understand the lifetime costs of unnecessary treatment. Then there are lawyers who argue that it is professional misconduct to warn the public about the corrupt continuing education seminars that push dentists to use unscientific approaches to care that are highly profitable for the dentist and the course sponsor. Is it really unethical to speak out when a health authority is aware of harm linked to certain approaches or are lawyers who attempt to bully whistle-blowers the ones that should be sanctioned? Malpractice awards in Canada are too low to make dental victims worthy of consideration. Change is needed.




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