Glucagon-Like Peptide-1 Receptor Agonist Use and Residual Gastric Content Before Anesthesia

Importance Glucagon-like peptide-1 receptor agonist (GLP-1 RA) use is rapidly increasing in the US, driven by its expanded approval for weight management in addition to hyperglycemia management in patients with type 2 diabetes. The perioperative safety of these medications, particularly with aspiration risk under anesthesia, is uncertain. Objective To assess the association between GLP-1 RA use and prevalence of increased residual gastric content (RGC), a major risk factor for aspiration under anesthesia, using gastric ultrasonography. Design, Setting, and Participants This cross-sectional study prospectively enrolled patients from a large, tertiary, university-affiliated hospital from June 6 through July 12, 2023. Participants followed preprocedural fasting guidelines before an elective procedure under anesthesia. Patients with altered gastric anatomy (eg, from previous gastric surgery), pregnancy, recent trauma (<1 month), or an inability to lie in the right lateral decubitus position for gastric ultrasonography were excluded. Exposure Use of a once-weekly GLP-1 RA. Main Outcomes and Measures The primary outcome was the presence of increased RGC, defined by the presence of solids, thick liquids, or more than 1.5 mL/kg of clear liquids on gastric ultrasonography. Analysis was adjusted for confounders using augmented inverse probability of treatment weighting, a propensity score–based technique. Secondarily, the association between the duration of drug interruption and the prevalence of increased RGC was explored. Results Among the 124 participants (median age, 56 years [IQR, 46-65 years]; 75 [60%] female), the prevalence of increased RGC was 56% (35 of 62) in patients with GLP-1 RA use (exposure group) compared with 19% (12 of 62) in patients who were not taking a GLP-1 RA drug (control group). After adjustment for confounding, GLP-1 RA use was associated with a 30.5% (95% CI, 9.9%-51.2%) higher prevalence of increased RGC (adjusted prevalence ratio, 2.48; 95% CI, 1.23-4.97). There was no association between the duration of GLP-1 RA interruption and the prevalence of increased RGC (adjusted odds ratio, 0.86; 95% CI, 0.65-1.14). Conclusions and Relevance Use of a GLP-1 RA was independently associated with increased RGC on preprocedural gastric ultrasonography. The findings suggest that the preprocedural fasting duration suggested by current guidelines may be inadequate in this group of patients at increased risk of aspiration under anesthesia.