Preoperative esophageal testing predicts postoperative reflux status in sleeve gastrectomy patients

Background: Patients who undergo vertical sleeve gastrectomy (VSG) are at risk of postoperative GERD. The reasons are multifactorial, but half of conversions to Roux-en Y gastric bypass are for intractable GERD. Our institution routinely performs preoperative pH and high-resolution manometry studies to aid in operative decision making. We hypothesize that abnormal pH studies in concert with ineffective esophageal motility would lead to higher rates of postoperative reflux after VSG. Methods: A single institution retrospective review was conducted of adult patients who underwent preoperative pH and manometry testing and VSG between 2015 and 2021. Patients filled out a symptom questionnaire at the time of testing. Postoperative reflux was defined by patient-reported symptoms at 1-year follow-up. Univariate logistic regression was used to examine the relationship between esophageal tests and postoperative reflux. The Lui method was used to determine the cutpoint for pH and manometric variables maximizing sensitivity and specificity for postoperative reflux. Results: Of 291 patients who underwent VSG, 66 (22.7%) had a named motility disorder and 67 (23%) had an abnormal DeMeester score. Preoperatively, reflux was reported by 122 patients (41.9%), of those, 69 (56.6%) had resolution. Preoperative pH and manometric abnormalities, and BMI reduction did not predict postoperative reflux status (p = ns). In a subgroup analysis of patients with an abnormal preoperative pH study, the Lui cutpoint to predict postoperative reflux was a DeMeester greater than 24.8. Postoperative reflux symptoms rates above and below this point were 41.9% versus 17.1%, respectively (p = 0.03). Conclusion: While manometry abnormalities did not predict postoperative reflux symptoms, GERD burden did. Patients with a mildly elevated DeMeester score had a low risk of postoperative reflux compared to patients with a more abnormal DeMeester score. A preoperative pH study may help guide operative decision-making and lead to better counseling of patients of their risk for reflux after VSG. Graphical abstract: [Figure not available: see fulltext.]