Negus & Anor v Guy's and St Thomas' NHS Foundation Trust

In clinical negligence, the court must determine breach by applying the Bolam test, subject to the requirement in Bolitho that the professional opinion relied upon has a logical and defensible basis. The court must weigh competing risks and benefits in the circumstances of the particular patient. The Montgomery test governs consent, requiring disclosure of material risks and reasonable alternatives; technical intra-operative choices need not be presented as simple treatment options. Causation ordinarily requires proof on the balance of probabilities under the “but for” test. The exceptional approach in Chester v Afshar requires evidence that the patient would have deferred or declined the procedure. A reasonable professional decision not to undertake a higher-risk procedure will not amount to negligence merely because another responsible body would have chosen differently.

This was a clinical negligence claim brought by the executors of Tracy Ann Neill’s estate against the NHS Trust responsible for St Thomas’ Hospital. Mrs Neill underwent aortic valve replacement surgery in 2014, during which a 19mm mechanical valve was implanted without an aortic root enlargement. She later underwent re-do surgery involving an aortic root enlargement and died in 2020.

The issues were whether implantation of the smaller valve was negligent; whether the consent process inadequately addressed the possible need for an aortic root enlargement; whether the alleged breach caused the complications during the re-do surgery; and whether it caused the later cardiac dysfunction and death.

1. Disposition. The claim was dismissed. The court found that implantation of the 19mm mechanical reduced valve was not negligent.
2. Breach in treatment. Applying Bolam v Friern Hospital Management Committee [1957] 1 W.L.R. 582, as qualified by Bolitho v City and Hackney Health Authority [1998] A.C. 232, the relevant question was whether the decision accorded with a responsible body of professional opinion and had a logical basis. The judge accepted that a reasonable body of cardiothoracic surgeons could choose the 19mm valve. The decision not to perform an aortic root enlargement was also rational because the root was fibrotic, the coronary ostia were close to the annulus, the procedure carried materially increased risks, and it was uncertain that a larger valve would result.
3. Consent. Applying Montgomery v Lanarkshire Health Board [2015] UKSC 11, the judge found a limited duty to warn of the possible risk that an aortic root enlargement might be required, particularly because that procedure would approximately double the operative risks. The duty did not extend to presenting the patient with a simple choice between a smaller valve and an enlargement, since the surgeon’s decision depended on technical findings and specialist intra-operative judgment. In any event, the evidence did not establish that different advice would have changed the decision to undergo surgery.
4. Causation. Applying ordinary causation principles, including the material-contribution approach discussed in Williams v Bermuda Hospitals Board [2016] UKPC 4, the judge found that any attempted enlargement in 2014 would probably have produced complications similar to those during the 2015 re-do operation. The claimants also failed to prove that the 19mm valve, rather than possible tissue overgrowth or mechanical failure, caused the later deterioration and need for re-do surgery. The exceptional rule in Chester v Afshar [2004] UKHL 41 did not assist because the necessary evidence of a different decision was absent.