Surgery is among the most consequential medical interventions a patient can undergo. The volume in Canada is enormous (hundreds of thousands of procedures every month), the range is wide (everything from minor outpatient procedures to multi-hour cardiac surgery), and the downside risks, when something goes wrong, can be catastrophic.
A bad surgical outcome is not, by itself, a negligent surgical outcome. Surgery carries recognized risks that can occur even with appropriate care, and the law of medical malpractice does not impose strict liability on surgeons. The legal question, in any case where a patient has been harmed in the surgical context, is whether the harm was caused by a failure to meet the standard of care that a reasonable surgeon would have met in the circumstances.
This post explains how surgical negligence claims are investigated, the points in the surgical care pathway where errors typically occur, and what it takes to prove a claim. It is written for patients and families who may have been harmed by surgical care, and for the lawyers who screen these cases.
A bad outcome is not a claim
The first point is the most important. Surgical claims are a substantial part of medical malpractice work in Ontario, and the cases that succeed do so because the harm flowed from a specific failure to meet the standard of care, not from the inherent risks of the procedure.
Many of the inquiries that come to my office concern surgical complications that are tragic but, on review, do not amount to negligence. The patient consented to the procedure with the understanding that complications could occur. The complications occurred. The complications were managed appropriately. The bad outcome was the realization of an inherent risk of surgery, not the consequence of substandard care.
In other cases, the breach is clear. A wrong-site surgery, a retained foreign object, a delayed recognition of a post-operative complication that should have been caught, or an informed consent process that misled the patient about the risks. In those cases, the breach is documented in the chart, and the claim turns on the harm caused.
The investigation is what distinguishes the two categories.
Three points in the surgical care pathway
A surgical malpractice review looks at three distinct phases of care: pre-operative, intra-operative, and post-operative. Each is a separate inquiry, each can be a separate basis for a claim, and a claim can rest on a failure at any of the three phases.
Pre-operative care
Pre-operative care is everything that led up to the surgery. The investigation focuses on whether the patient was an appropriate candidate for the procedure that was performed.
Specific issues that arise in pre-operative review:
- Indication. Was surgery actually indicated, or was the patient steered toward a procedure that was not the best management for their condition? In some cases, the better answer was conservative management, watchful waiting, or a different surgical approach
- Workup. Were the necessary investigations (imaging, laboratory work, specialist consultation) performed and accurately interpreted? An inappropriately interpreted CT scan or MRI can set off a cascade of downstream errors
- Diagnosis. Was the underlying condition correctly diagnosed before the patient was committed to surgery? Surgical claims sometimes start as misdiagnosis claims, where the surgeon operated on a diagnosis the workup did not actually support
- Timing. Was the surgery performed at an appropriate time? In some cases, earlier intervention would have produced a better outcome (a cancer caught when smaller and more confined is generally easier to remove than one that has progressed)
- Informed consent. Was the patient given the information needed to meaningfully consent to the procedure? The Supreme Court of Canada in Reibl v Hughes established that consent requires disclosure of material risks, the risks of no treatment, and the alternatives. The Ontario Court of Appeal’s decision in Denman v Radovanovic clarified that the duty extends to all advising physicians on a multi-disciplinary team, not only to the surgeon performing the procedure
Intra-operative care
Intra-operative care is the surgery itself. This is the area patients most often focus on, and it is also the most evidentially difficult.
Recurring intra-operative issues:
- Surgical technique. Did the surgeon follow standard surgical technique? Standard technique is the body of practice that defines what a competent surgeon does at each step of a procedure. Departure from standard technique that causes harm is the prototypical surgical negligence claim
- Vascular and organ injury. Many surgical procedures take place in close proximity to important blood vessels and organs. Inadvertent injury to these structures can be a recognized risk of the procedure (in which case it is often not negligent) or the consequence of substandard technique (in which case it usually is)
- Wrong-site surgery. Operating on the wrong limb, the wrong side, the wrong organ, or the wrong patient. These are “never events” in patient safety terminology and are almost always the result of a breakdown in pre-surgical verification protocols
- Retained foreign objects. Surgical instruments, sponges, or other material left inside the patient. These too are “never events” and are almost always indefensible
- Anaesthesia errors. Medication errors (wrong dose, wrong drug, incompatible drug), airway management issues, or failure to recognize and respond to physiological changes during the procedure
- Surgeon experience and credentialing. In some cases, the issue is whether the surgeon was appropriately trained and credentialed to perform the procedure at all
The principal difficulty in intra-operative claims is evidentiary. The patient is generally under general anaesthesia and has no first-hand knowledge of the procedure. The operative record (the surgeon’s dictated note describing the operation) is the central piece of evidence, and it is created by the very person whose conduct is in issue. The anaesthesia record, the nursing notes, and the perioperative records can fill in some of the picture, but the operative note remains the dominant document.
A serious complication may be described in an operative note that records a routine and uneventful procedure. When that happens, the analysis turns to whether the complication that occurred could have happened without negligence, given the procedure performed and the technique described. That is an expert question, and can be a difficult one.
Post-operative care
Post-operative care is what happens after the patient leaves the operating room. The principal issue in this phase is the timely recognition of complications.
Specific patterns:
- Post-operative infection and sepsis. Wound infections and intra-abdominal sepsis after abdominal surgery, ventilator-associated pneumonia, urinary tract infections from catheter use. Recognized early, these are manageable. Recognized late, they can be catastrophic
- Bowel injury after abdominal surgery. A bowel injury sustained during surgery (whether recognized at the time or not) can produce sepsis and peritonitis if not treated. Post-operative deterioration, persistent abdominal pain, and abnormal vital signs after abdominal surgery should prompt urgent reassessment
- Bleeding. Post-operative haemorrhage requires prompt recognition and treatment. Delays can produce shock and end-organ damage
- Anastomotic leak. Where the surgeon has joined two ends of bowel or another tubular structure, the anastomosis can leak. This is a recognized risk and manageable when caught early
- Compartment syndrome. Particularly relevant after orthopedic and vascular procedures
- Discharge errors. Discharging a patient too early, without appropriate follow-up arrangements, or without adequate education about warning signs that should bring them back
Post-operative care responsibilities are shared between surgeons (who carry primary responsibility), nurses (who carry the front-line monitoring responsibility), and other physicians involved in post-operative management. Where post-operative complications produce harm, the analysis often involves looking at the role of each professional involved in the patient’s care.
Some post-operative complications take days or weeks to present, after the patient has been discharged. Where the patient presents to the emergency department with a post-operative complication, an additional layer of potential negligence (a missed or delayed diagnosis in the ER) can be added on top of the original surgical issue.
Specific surgical contexts
The framework above applies to all surgical claims, but some specific surgical contexts come up frequently enough to warrant a brief note:
- Caesarean sections and birth injury. Caesarean sections are among the most frequent surgeries in Canada, and the most concerning complications relate to birth injury. The classic fact pattern involves a delayed decision to proceed to Caesarean delivery despite signs of fetal distress, resulting in a hypoxic brain injury and lifelong disability for the child. For more, see the Birth Injury practice page
- Fracture and orthopedic surgery. Issues here typically involve the timing of surgery, the surgical approach, the management of vascular complications, and the management of compartment syndrome
- Abdominal and pelvic surgery (appendectomy, cholecystectomy, hysterectomy, colectomy). The most common medical-legal concerns are bleeding, injury to adjacent organs (bowel, ureter, bladder), infection, and post-operative anastomotic leak
- Neurosurgery. A small but high-stakes category. Procedural risks are substantial, the consequences of harm are catastrophic, and informed consent issues (as in Denman v Radovanovic) can be central
The legal framework
A surgical malpractice claim follows the same legal framework as any medical malpractice claim in Ontario. The plaintiff must prove:
- The healthcare professional fell below the standard a reasonable practitioner would have met in the circumstances (breach of the standard of care)
- The substandard conduct caused a worse outcome than would otherwise have occurred (causation)
- The worse outcome produced compensable harm (damages)
In the surgical context, each element has particular features.
Standard of care is generally proven by expert evidence from a surgeon in the same subspecialty as the defendant. The Ontario courts will not allow a vascular surgeon to opine on the standard of care for a neurosurgeon, and the expert must speak to what a reasonable surgeon, with the same training and in similar circumstances, would have done. There is a limited exception, established by the Supreme Court of Canada in ter Neuzen v Korn, that a non-technical breach (a “common sense” failure that does not require specialized knowledge to identify) can in rare cases be found without specialty-specific expert evidence. See Drain v Ziesmann for an Ontario application of that exception in the surgical context.
Causation is often the most difficult element in surgical claims. The question is not whether the breach occurred, but whether the breach caused a worse outcome than would otherwise have followed. A surgeon’s poor technique that caused a known surgical complication is one thing; a surgeon’s poor technique that produced a catastrophic injury that would otherwise not have happened is another. Cases like Knight v Lawson illustrate how a surgical claim can be lost on causation even where the underlying conduct is open to criticism.
Damages must reflect actual compensable harm beyond what would have occurred without the breach. Where the patient would have had a difficult outcome regardless of the breach, the damages are limited to the marginal harm caused by the negligence, not the entire bad outcome.
Why expert evidence is essential
Surgical claims, more than almost any other category of medical malpractice claim, depend on expert evidence. The expert is needed to:
- Identify what the standard of care required in the circumstances
- Identify whether the surgeon’s conduct, as documented in the records, departed from that standard
- Identify whether the harm the patient suffered was caused by the departure from the standard, rather than by the inherent risks of the procedure or by the underlying condition
A surgical claim without an expert opinion supporting all three points is generally not viable. Lawyers experienced in this area will not commit a client to litigation without a supportive expert review of the records.
Why this matters
For patients and families. A bad surgical outcome is not, by itself, a malpractice claim. The first step is to obtain the medical records (the operative note, the anaesthesia record, the nursing notes, the post-operative records, and any imaging or laboratory results) and consult with a lawyer experienced in this area. The investigation will look at all three phases of care (pre-operative, intra-operative, post-operative) and will ultimately depend on a supportive expert opinion to move forward. Many surgical inquiries do not, on review, support a viable claim. That is not because surgical errors are rare. It is because separating an error from a recognized complication requires careful analysis.
For prospective claimants screening their own situation. Look at the three phases. Was the indication for surgery sound? Were the pre-operative investigations and consent process appropriate? During the procedure, did the surgeon follow standard technique, and did the operative note candidly describe what happened? After the procedure, was the post-operative care responsive to changes in the patient’s clinical status? Where the answer to one or more of these questions is “no” and the harm is significant, a legal review may be worthwhile.
For lawyers screening these cases. The screening question in surgical claims is whether the available expert opinions can support breach, causation, and damages. Cases are stronger where the operative record is incomplete or inconsistent with the patient’s clinical course, where the breach falls into a recognized “never event” category, or where post-operative deterioration was clinically obvious and not acted upon. Cases are harder where the operative note describes a routine procedure with a recognized complication and the post-operative course is well-documented.
For more on the legal process for medical malpractice claims in Ontario, see Suing for Medical Malpractice in Ontario: What You Need to Know. For the threshold question of whether a particular fact pattern supports a viable claim, see Can I Sue for Medical Malpractice in Ontario? For information on obtaining the records that drive any surgical investigation, see How to Get Your Medical Records in Ontario. For the Surgical Errors practice page, see the linked overview.
