Extracting Informed Consent
Winterbotham v Shahrak [2024] EWHC 2633 (KB)
Background
In Winterbotham, the Claimant had suffered a partially erupted wisdom tooth for many years, which had caused several episodes of pericoronitis (inflammation of the surrounding gum tissue) with associated pain and discomfort. Because of the lengthy wait for NHS treatment, the Claimant sought private treatment and was referred to the Defendant’s practice.
The Defendant extracted the tooth, and the procedure was performed with reasonable care and skill. However, the inherent risk of lingual nerve damage materialised, and the Claimant alleged that the Defendant had not warned her about this, thereby failing to obtain her informed consent to the treatment. Further, the Defendant should have advised her of an alternative coronectomy (removal of the crown but not the root). The alternative coronectomy did not involve the risk of nerve damage but may have required a revision procedure.
Summary
In summary, the judge found that liability was established. The Defendant had failed to gain the Claimant’s informed consent, breaching his duty of care. The Claimant was successful on causation on a conventional “but for” basis. Her secondary case on causation, based on Chester v Afshar [2004] UKHL 41, would also have been successful.
Breach
Winterbotham provides an important reminder that material risks must be disclosed to patients in a comprehensible way (Montgomery v Lanarkshire Health Board [2015] UKSC 11). In particular, it illustrates that a patient simply signing a consent form detailing the material risks is not good enough. Clinicians must clearly draw the patient’s attention to risks and quantify them appropriately:
[62] “at the consultation Mrs Winterbotham should have been taken through the consent form by Dr Shahrak. That should have entailed a meaningful opportunity to ask questions and a discussion of the material risks that were relevant to her.”
The case also provides one of the first applications of McCulloch v Forth Valley Health Board [2023] UKSC 26, which held that the Bolam/Bolitho test applied to the determination of whether an alternative treatment was “reasonable.” Both experts agreed that coronectomy was a reasonable alternative and ought to have been disclosed. However, interestingly, even though the Defendant himself would not perform a coronectomy, the justification for disclosure was that there was the possibility that the Claimant could go elsewhere for the treatment.
Causation
The judge was satisfied that the Claimant would not have undergone an extraction because she would have opted for a coronectomy and therefore causation was made out on a conventional “but for” basis. However, he still considered the Claimant’s alternative case on causation based on Chester.
The Court summarised the principle that can be extracted from Chester as:
[87] “where there has been a failure to explain a material risk and the patient suffers an injury which is a result of the risk which should have been warned about but, if properly advised of the risk, she would have undergone the same procedure on a later date, causation is established.”
Applying Chester, even if the Claimant had not proven that “but for” the negligence she would not have undergone the extraction and instead would have undergone a coronectomy, the judge found that she would have deferred the extraction.
Winterbotham also considers obiter that Wallace v Kam [2013] HCA 19, an Australian authority, applies in English law. Wallace is authority for the proposition that where several material risks are not disclosed, the claimant must demonstrate that the risk which in fact materialised would have been decisive in them not undergoing the treatment or at least deferring it. It is insufficient for a claimant to show that they would not have proceeded with or deferred the treatment because of the inadequate disclosure of a different risk which did not materialise.
On this point, the judge found that there was a clear failure to advise of the risk of injury to the lingual nerve, the risk which materialised, and therefore the principle in Wallace was not invoked. However, he went further and held that, as risks to the lingual nerve and inferior alveolar nerve were treated compendiously as “nerve damage” on the consent form, a Wallace-type distinction was not possible:
[90] “The relevant breach was a failure to advise that this was a high as opposed to ordinary risk procedure when looking at the lingual nerve and IAN together. Nerve injury eventuated and that was precisely the injury which should have been warned about.”
Therefore, where several risks are treated compendiously in a consent form, and one of those risks materialises, that is sufficient to prove causation.
Comment
Winterbotham does not establish any new principles, but rather reaffirms the existing position. There are three key takeaways:
(i) Informed consent cannot simply be gained through a signature on a consent form. The specific consequences of a risk must be explained in the context of the patient’s subjective characteristics. The patient should be taken through the consent form.
(ii) Causation under Chester is established where a patient would have undergone the same treatment but at a later date. Although there had been a previous lack of clarity about what Chester stands for, Winterbotham provides further authority articulating a clear principle (see e.g. Correia v University Hospital of North Staffordshire NHS Trust [2017] EWCA Civ 356).
(iii) There is now obiter authority that Wallace v Kam applies in English law. Where a defendant fails to disclose more than one material risk, the claimant must show that it is the risk that in fact materialised that would have been decisive in her refusing to consent to (or deferring) treatment. However, risks treated compendiously on a consent form will not be distinguished for the purposes of causation.
