Introduction Sleeve gastrectomy is increasingly used as both a definitive and staggered weight loss procedure. The effect of sleeve gastrectomy on gastro-oesophageal reflux (GOR) remains uncertain. We studied the effect of sleeve gastrectomy on GOR, pressure parameters at the Lower Oesophageal Sphincter (LOS), oesophageal and gastric motility.

Methods Sixteen patients (median age 46 (range 25–71)) with morbid obesity underwent high resolution oesophageal manometry and 24hr ambulatory pH-impedance monitoring, at least 2 weeks pre-op and 3 months post sleeve gastrectomy (median no. of days post-op 129 (range 84–202)). All patients documented reflux and dysphagia symptoms at the time of testing. Nine patients also underwent concurrent gastric emptying with 13C labelled octanoate breath test. Parametric data was analysed using the paired t-test and non-parametric data with Wilcoxon matched pairs test.

Results Mean Body Mass Index (BMI) fell from 49 (41.3–58.3) to 38.5(35–46.3). 5/16 patients reported new or worsening reflux symptoms (31%). Basal LOS pressure fell from 14.4mmHg (9.7–28.5) pre-op to 8.9mmHg (0.7–40.5) post-op (p < 0.02). Intra-gastric pressure and G-O pressure gradient increased: 8.3mmHg (4.7–12.8) pre-op Vs 10.4 mmHg (5.3–22.7) post-op (p < 0.01). 8/16 patients had severe hypomotility pre-op and 9/16 post-op. 3/16 patients had pathological acid reflux pre-op, 5/16 patients having de novo reflux post-op. Mean total acid exposure time pre-op was 1.8%(0.5–5%) increasing to 4.35% (0.2–12.4%)(p < 0.02) post-op. There was an increase in the number of acid: 18(8–31) pre-op vs 29(13–38) post-op (p < 0.0001), and non-acid reflux episodes: 13(7–19) pre-op vs 52(35–84) post-op(p < 0.0001). Non-acid reflux episodes occurred predominantly in the post-prandial period. Gastric half emptying time(t1/2) was significantly shorter post-op 193.1mins (range113–433) vs 115.8 mins (range 82–170) (p < 0.05).

Conclusion Both acid and non-acid gastro-oesophageal reflux is increased after sleeve gastrectomy with 31% of patients developing de novo acid reflux post-op. This is despite a reduction in BMI and accelerated gastric emptying. A reduction in LOS pressure and increased G-O pressure gradient are likely to be contributing factors. Future studies should determine whether decreased gastric compliance stimulates increased numbers of transient lower oesophageal sphincter relaxations.

Disclosure of Interest None Declared