Gastric residual volume in patients with obesity receiving GLP-1 receptor agonists: A comparative gastric ultrasound pilot study
Abdulaziz Ejaz Ahmad, Nada Tariq Yamani, Abdulaziz Fahad Alaqaili, Sadeem Saleh Aldawas, Najla Qatnan Alotaib, Abdelazeem Ali EldawlatlyAbstract
Background:
Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) enhance insulin secretion, suppress glucagon release, promote satiety, and may slow gastric emptying. Introduced in 2005 for the treatment of type 2 diabetes and obesity, these agents have prompted interest in assessing delayed gastric emptying as a potential biomarker to predict treatment response and to guide decisions regarding long-term therapy. Point-of-care gastric ultrasound (POCUS) offers a bedside method to assess gastric contents.
Objectives:
To compare gastric residual volume (GRV) on gastric ultrasound among patients with obesity receiving GLP-1 RAs and nonusers and those with prior weight loss surgeries.
Methods:
In this comparative cross-sectional pilot study, gastric POCUS was done on patients with obesity who took GLP-1 RAs and other patients with obesity with no history of taking GLP-1 RAs prior to surgery in the supine and lateral decubitus positions. Antral cross-sectional area and GRV were measured using validated mathematical models.
Results:
Patients receiving GLP-1 RAs demonstrated higher estimated GRV compared with nonusers. A higher proportion of GLP-1 RA users met ultrasound criteria for a full stomach.
Conclusion:
Among patients with obesity, GLP-1 RA therapy was associated with enlargement of the gastric antrum, increased gastric volume, and greater residual gastric contents, leading to an elevated estimated risk of aspiration. This increased risk is primarily determined by gastric ultrasound findings rather than patient characteristics, comorbidities, or duration of treatment. Gastric ultrasound may support individualized perioperative decision-making regarding aspiration precautions.