Relationship between residual gastric content and peri-operative semaglutide use assessed by gastric ultrasound: a prospective observational study

Background: Semaglutide is a long-acting glucagon-like peptide-1 receptor agonist known to delay gastric emptying. Despite a growing body of evidence, its peri-operative safety profile remains uncertain, particularly with regard to the risk of increased residual gastric content and aspiration of gastric contents during anaesthesia. We hypothesised that semaglutide interruption of ≤ 10 days before elective surgical procedures is insufficient to reduce or normalise the residual gastric content, despite fasting intervals that comply with current guidelines.

Methods: In this prospective observational study, we recruited patients who received pre-operative once-weekly subcutaneous semaglutide within 10 days of the procedure (semaglutide group) and control patients who had not been exposed to semaglutide (non-semaglutide group). On the day of surgery, all patients underwent pre-operative point-of-care gastric ultrasound to evaluate their residual gastric content. Increased residual gastric content was defined as any solid content or > 1.5 ml.kg^-1 of clear fluids as assessed by gastric ultrasound.

Results: We recruited 220 patients, 107 in the semaglutide group and 113 in the non-semaglutide group. Increased residual gastric content was found in 43/107 patients (40%) in the semaglutide group and 3/113 (3%) in the non-semaglutide group (p < 0.001). In propensity-weighted analysis, semaglutide use (OR 36.97, 95%CI 16.54-99.32), age (OR 0.95, 95%CI 0.93-0.98) and male sex (OR 2.28, 95%CI 1.29-4.06) were significantly associated with increased residual gastric content. There were no cases of pulmonary aspiration of gastric contents.

Conclusion: Pre-operative semaglutide use within 10 days of elective surgical procedures was independently associated with increased risk of residual gastric content on pre-operative gastric ultrasound assessment.