BN O05 - Physiological Transit Assessment of the Oesophagus In Patients With Anti-Reflux Surgery

Abstract Background High-resolution manometry (HRM) is the gold-standard investigation for oesophageal motility in patients with dysphagia. The HRM findings may influence surgical decision for myotomy or anti-reflux surgery (ARS). However, HRM pitfall is the inability to measure oesophageal transit in parallel to the motility during physiology testing. Both transit and motility are complementary that offer insights in the pathophysiology and aetiology of the dysphagia symptoms. This research evaluates the multichannel intraoesophageal impedance transit (MIIT) concept [1] to assess the oesophageal transit in symptomatic patients who undertook the postoperative oesophageal physiology testing between January 2020 and June 2024. Method This cross-sectional retrospective study selected patients with intact Nissen fundoplication (NF) wrap on gastroscopy or with known LINX implant in-situ. HRM with Chicago Classification (version 4.0)[2] compared the ARS cases with augmented antireflux barrier [AARB] from the surgery to healthy treatment naïve controls. The multichannel impedance-pH studies assessed both reflux and the MIIT [1]. MIIT >0.76 minutes were considered positive and comparable to GOJ outflow obstruction [1]. This project was approved by the NHS institution and the local research ethics committee (REC 18/NW/0120)(IRAS 333800). Results 60 patients were found (NF 54, LINX implant 6)(females 30, mean age 51.3 years). 11 patients(18.3%) had pathological reflux despite ARS(DeMeester scores >14.72); 2 patients (18.2%) demonstrated hypotensive AARB. Conversely, 6 patients(10%) showed poor relaxation from the AARB and were compatible to outflow obstruction (5 patients [83.3%] showed conformation with MIIT >0.76 minutes). Patients with ineffective oesophagus (20%) and absent contractility(11.7%) showed MIIT >0.76 minutes in respectively two-thirds with ineffective oesophagus and in all patients with absent contractility. Normal HRM study was observed in 35 patients (58.3%) with 27 patients (77.1%) demonstrating MIIT >0.76 minutes. Conclusion MIIT was able to explain the post-surgical dysphagia in majority of patients from the equivalent transit to outflow obstruction (n=52 patients, 86.7%). Half of these cases had a normal HRM study and would have been perceived as having functional dysphagia. We would recommend performing MIIT adjunctive testing as part of postoperative oesophageal physiology assessment in symptomatic patients. Incidentally, we observed 16 patients (26.7%) having hypotensive AARB post ARS comparing to healthy treatment naïve controls with 2 patients (12.5%) having persistent pathological reflux who may still benefit from surgical revision. References [1] https://doi.org/10.1136/gutjnl-2020-bsgcampus.41 [2] https://onlinelibrary.wiley.com/doi/10.1111/nmo.14058