Determining Reliability in Clinical Negligence Litigation – Evidential and Expert Considerations

Clyde & Co successfully represented a Consultant Upper GI and Bariatric Surgeon, an MDDUS member, at a trial which concerned a decision to undertake balloon dilatation following sleeve gastrectomy surgery.

This decision highlights the importance of the reliability of both factual and expert witnesses in clinical negligence proceedings. Clyde & Co instructed Anna Hughes of 2 Temple Gardens on this case.

Introduction

The Claimant (C) met with the Defendant (D) in 2019 to explore the possibility of weight loss surgery. C elected to undergo the procedure after she had been reviewed by D and his specialist bariatric team, including a dietitian, psychotherapist and bariatric nurse, who found C to be a suitable candidate. Surgery took place in September 2019. 

At a review four weeks after surgery, C complained of even sloppy textured food getting stuck in her throat. D performed a barium swallow, which suggested a mild delay or hold up of contrast at the gastro oesophageal junction (GOJ). The Claimant continued to struggle with eating and four weeks later D undertook a diagnostic gastroscopy where he concluded that a possible narrowing may be causing her symptoms. Accordingly, the Claimant was consented for a balloon dilatation, which D undertook. Unfortunately, C suffered a recognised complication of this procedure, a leak of the gastric sleeve, requiring conversion of the sleeve to a gastric bypass. At the time of trial, C was sadly still suffering from ongoing symptoms of vomiting with poor oral intake, and malnutrition. 

At the time of issue of proceedings, D was extensively criticised for failing to appropriately consent C for surgery, and for the performance of the sleeve gastrectomy itself. These formed over half of the allegations pleaded. However, just weeks before trial, C discontinued all of these allegations and the focus of the case remained only on the post operative care. This left the following issues to be determined at trial:

(i)     Whether there had been a breach of duty by D in failing to provide C with reasonable post-operative care following the sleeve gastrectomy;
(ii)    Whether there had been a breach of duty in proceeding with the balloon dilatation;
(iii)   Whether the breach(es) of duty caused injury or damage to C.

It was accepted by D in advance of the trial that should breach of duty be established in respect of the performance of the balloon dilatation, then causation would be established in full. 

A 3 day trial took place before HHJ Simon at the Royal Courts of Justice beginning in June 2025. 

Legal arguments

In support of the allegations of breach of duty, C argued that D and the bariatric nurse failed to document C’s reports of difficulties with vomiting and food progression. D and the bariatric nurse gave evidence that such important information would have been recorded had it been reported by C, and indeed when these issues were reported, the bariatric nurse immediately requested D’s input, which led to further investigations.

It was also argued by C that as there was no good evidence of stricture on the barium swallow, further conservative treatment measures should have been attempted before embarking on the dilatation. This was supported by the evidence of the Claimant’s expert Upper GI/Bariatric Surgeon, who was strongly of the view that balloon dilatation was only to be conducted in the presence of confirmed stricture. However, as the trial progressed, this expert was unable to provide concrete definitions of the terms “stricture”, “stenosis” and “narrowing” which led to him lacking a coherent basis for the position he adopted.  He sought to add that C’s symptoms could be alternatively explained by dysmotility, but ultimately conceded that narrowing was top of the list of possibilities.

D argued that the barium swallow did evidence stenosis, as supported by the opinion of his expert Upper GI/Bariatric Surgeon. D’s expert was praised by the Judge for his careful and intelligible explanation of what was encompassed by “stricture”, “stenosis” and “narrowing”, and made clear in his opinion that the evidence of stenosis made the performance of the balloon dilatation reasonable.

Judgment was reserved and handed down in October 2025.

Outcome

The Claimant’s claim was dismissed. HHJ Simon acknowledged the extremely serious consequences that C suffered as a result of the sleeve leak, and expressed the Court’s every sympathy for C’s serious and continuing health challenges. However, he concluded that the claim against D was simply not made out, even on the more limited basis advanced at trial.

The Judge was not persuaded that the support offered by the team to C was anything other than a reasonable equivalent of what would be offered in the NHS. It was improbable that D or his team would not have documented communications from C concerning highly relevant and important information such as her difficulties with vomiting or food progression, and D’s MDT working model was found to be a perfectly proper system for sharing expertise and being patient-focussed. The Defendant and his clinical team were found to be credible witnesses and their evidence was reliable. 

HHJ Simon accepted D’s evidence that the holistic picture was highly suggestive of narrowing in the area of the GOJ. Further, he found that the Defendant’s expert had considered the relevant literature thoroughly, roundly undermining the explanations put forward by his counterpart. The Claimant’s expert was criticised for not clearly having at least a basic understanding of the legal parameters within which he was asked to express his opinion, for his evidence being difficult to understand due to his inconsistent use of terminology, and for not responding adequately to cross-examination. This was contrasted with the evidence of the Defendant’s expert, who was entirely coherent and supported his opinion by reference to the medical literature.

Learning points

1. A Claimant need not be found dishonest for their evidence not to be accepted. The Claimant’s credibility was not criticised by the Judge (or indeed the Defendant) at trial, but the Judge acknowledged it would be surprising if the passage of time and traumatic nature of the events did not have a detrimental impact on her recollection. This goes to show that factual evidence can be challenged on reliability, without having to pursue any allegations of dishonesty.
2. It is important to evidence how a clinical team can work together, not just as individuals, to support a patient’s journey. Having a robust MDT model in place, and calling other members of the MDT as witnesses, can help to prove the level of support provided to patients.
3. Finally, it is crucial that a party’s expert is able to demonstrate an adequate understanding of the Bolam test and justify their evidence with clarity, being able to explain complex terminology as necessary.