241. EVALUATION OF THE PYLORUS FOLLOWING GASTRIC CONDUIT RECONSTRUCTION IN OESOPHAGECTOMY USING IMPEDANCE PLANIMETRY—A SYSTEMATIC REVIEW WITH META-ANALYSIS

Abstract

Abstract Gastric conduit dysfunction (GCD) is one of the most challenging late complications of oesophagectomy and can have a significant detrimental effect on patient’s quality of life. Functional obstruction at the pylorus may be a contributory factor, however, few studies have directly examined the physiology of the pylorus in the gastric conduit. This review aims to determine if impedance planimetry (IP), using EndoFLIP®, can be used to demonstrate a significant alteration in pyloric physiology following oesophagectomy. We conducted a systematic literature search using EMBASE and MEDLINE to identify studies that compared results of IP analysis using EndoFLIP® in healthy volunteers with patients following oesophagectomy for oesophageal cancer. Selection of studies was conducted in line with the PRISMA guidelines against pre-determined inclusion criteria and the review was registered with PROSPERO (CRD42023401664). Meta-analysis, using a pooled mean and mean difference, was conducted to determine whether there was a significant difference in mean pyloric distensibility index (DI), a widely used and validated measure of sphincter functioning, following oesophagectomy with gastric conduit reconstruction compared to healthy volunteers. A total of 2751 studies were identified following database search and four studies were deemed eligible for inclusion. All studies reported mean pyloric DI values following oesophagectomy and protocols for EndoFLIP® analysis were consistent. The pooled mean pyloric DI from all studies (n = 109) was 9.12mm2/mmHg following oesophagectomy, compared to a pre-validated normal value of 25.2mm2/mmHg in healthy volunteers. Mean difference calculation, using a fixed effects model, from two studies including original results for healthy volunteers (n = 42) and patients following oesophagectomy (n = 14), showed that pyloric distensibility was 14.41mm2/mmHg higher in healthy volunteers compared to those post-oesophagectomy (95% CI 11.81–17.00, p < 0.00001). Studies suggest that pyloric distensibility is significantly reduced following oesophagectomy compared to healthy volunteers. A lack of pyloric distensibility may adversely affect gastric conduit emptying and contribute to GCD. It remains unclear whether DI measurements will correlate with severity of GCD or show changes pre- and post-operatively for individual patients. The effect of surgical pyloroplasty on pyloric distensibility and physiology needs to be examined as a potential means of reducing the incidence of GCD.