Case file: Claim

Bariatric surgery consent

Two people signing a contract
  • Date: 25 October 2022
  • |
  • 4 minute read


Mr G is 43 years old and with a BMI of 33.2 meets the diagnostic criteria for clinical obesity. He has tried dieting and exercise and has attended NHS weight loss clinics but has been unsuccessful in his attempts to reduce his weight.

Mr G attends his GP to request a referral to a private gastrointestinal surgeon for potential bariatric surgery. The surgeon, Mr R, undertakes a detailed history and examination, during which Mr G states he has recent-onset type 2 diabetes and borderline hypertension.

Options are discussed along with risks, benefits and potential complications and Mr G states a preference for sleeve gastrectomy. Mr R refers the patient to an endocrinologist for a diabetic review and his HbA1c is measured at less than 10 per cent.

A month later Mr G attends hospital for the procedure. He is again informed of potential complications/risks including bleeding, infection, staple line leak, abscess and dysphagia. He signs a consent form and the sleeve gastrectomy is undertaken without incident. He is discharged two days later.

A few weeks later Mr G attends an outpatient appointment at the gastro clinic. He reports problems including a feeling of food getting stuck when he eats and also some nausea. This is investigated with a barium swallow which indicates some “hold-up” in the lower oesophagus, and an endoscopy which suggests a possible torsion of the sleeve.

An exploratory laparoscopy reveals dense scar tissue of visceral fat causing extrinsic stenosis. Two days later Mr G undergoes a gastric bypass, and post-operative gastrograffin swallow shows free passage of contrast through the anastomosis with no evidence of leak or hold up.

Mr G has a long recovery with ongoing nausea, reflux and oesophageal spasm.

Six months post-surgery, a letter is sent to Mr R by solicitors claiming clinical negligence in the treatment of Mr G. Among the allegations is that at a BMI of 33.2 the patient did not fall within the criteria for recommended bariatric surgery according to NICE guidelines (over 40 BMI, or 35-40 BMI with significant comorbidities including type 2 diabetes).

The letter also alleges that Mr R failed to obtain adequate consent prior to the surgery by informing him of all relevant risks, including the potential need for further surgery. It also states that Mr G was not given adequate time to consider and assess those risks, with the consent form signed on the day of surgery.

The letter further claims that had Mr G been adequately advised of the potential risks he would not have agreed to the surgery and would have thus avoided subsequent complications and the need for further surgery.


An MDDUS medicolegal team reviews the evidence in the case and commissions an expert report from a consultant surgeon to consider the alleged breach of duty and causation (consequences of that breach).

The expert considers the allegations and advises that Mr G (with a BMI of 33.2) was a suitable candidate for bariatric surgery. NICE guidance states that weight loss surgery may be beneficial for people with a BMI of 30-34.9 who have recent-onset type 2 diabetes that is poorly controlled, or in obese patients of Asian family origin.

The expert also concludes that informed consent was obtained prior to surgery. She points out that consent is a dynamic process and extends beyond the consent form itself.

The records show there was extensive discussion of potential risks/benefits of the various surgical options both at the initial consultation and on the day of the surgery. This discussion was supported with an animated video of procedures and an illustrated leaflet on laparoscopic sleeve gastrectomy, which set out the risks in detail.

The consent process allowed ample opportunity for reflection and opportunity to ask questions and raise any concerns in advance of the procedure.

In regard to causation, the expert points out that Mr G had requested a referral for private bariatric surgery and the records reveal that he had wanted this for many years. There is no allegation that the procedure was carried out in a negligent or substandard manner, and Mr G was fully informed of the risks and benefits of the procedure. He freely chose to go ahead with the operation and would have always done so, thus requiring the same further surgery to manage the unforeseen complications.

A letter of response is drafted incorporating the expert views and rebutting the allegations and the case is subsequently discontinued.


  • Ensure treatment decisions are justified in the patient notes.
  • Provide ample time for patients to understand treatment options discussed along with benefits/risks.
  • Ensure the consent process, including discussion of risks/complications and the provision of written/visual aids to assist patient understanding, is recorded in the patient record.

This page was correct at the time of publication. Any guidance is intended as general guidance for members only. If you are a member and need specific advice relating to your own circumstances, please contact one of our advisers.

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