• In the case of Chester v Afshar 2005 1 AC 134 it was found that a neurosurgery who failed to warn a patient of the small risk of injury inherent in surgery, even if properly performed, was liable to the patient when that risk eventuated, even though the risk was not increased by the failures to warn and the patient had not shown that she would never have had an operation carrying the same risk.
  • Failure to advise on risk in medical procedures will lead to negligence liability even where causation cannot be made out.

Facts of the Case

  • A consultant neurosurgeon the appellant, appealed against a finding that he was liable in damages for his failure to warn the respondent of a risk inherent in surgery that he had performed on her.
  • The respondent suffered repeated episodes of lower back pain and had been referred to surgery by the appellant who was experienced in disc surgery.
  • The respondent underwent the surgery and suffered a rare complication known as cauda equina syndrome which was a risk that the appellant had failed to warn her about in advance of the surgery.
  • The judge at first instance had not found that the appellant had been negligent in the actual performance of the surgery.
  • The judge did find that the appellant had failed to warn the respondent of the small risk that the operation could affect her and that had she been warned of the risk, she would not have undergone the surgery at the time she did.  

Issues in Chester v Afshar 2005 1 AC 134

  • The issues in the case relate to where the liability pointed for the respondents’ injuries and whether causation could be proved between, the surgery, lack of advice and the subsequent condition contracted by the respondent.

Held by House of Lords.

  • The appeal by the neurosurgeon failed.

Lord Steyn, Lord Hope, Lord Walker (Majority)

  • A judgment in the respondent’s favour could not be based on conventional causation principles.
  • The “but for” test was satisfied sine the respondent would not have had the operation when she did if the warning had been given.
  • The risk of which she should have been warned was not created by the failure to warn, it was already there as an inevitable risk of the operative procedure itself however skilfully and carefully it was carried out.
  • The risk was not greatened or lessened by the surgeon not mentioning it, but it was the duty of the surgeon to warn of the inherent dangers.  

Lord Bingham, Lord Hoffmann dissenting

  • The issue of causation was to be addressed by reference to the scope of the doctor’s duty, namely, to advise his patient of the disadvantages or dangers of the treatment he proposed; that such a duty was closely connected with the need for the patient’s consent and was central to her right to exercise an informed choice as to whether and, if so, when and from whom to receive treatment; that, since the injury she sustained was within the scope of the defendant’s duty to warn and was the result of the risk of which she was entitled to be warned when he obtained her consent to the operation in which it occurred, the injury was to be regarded as having been caused by the defendant’s breach of that duty; and that, accordingly, justice required a narrow modification of traditional causation principles to vindicate the claimant’s right of choice and to provide a remedy for the breach.