Extended Fasting, GLP-1 RA Withholding, and Gastric POCUS Reduce Peri-Procedural Residual Gastric Content

The widespread use of Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RAs) for weight management and diabetes has introduced new challenges in peri-procedural care. A primary concern is the delayed gastric emptying induced by GLP-1 RAs, which can lead to increased residual gastric content (RGC). This elevated RGC poses a significant pulmonary aspiration risk during elective procedures requiring anesthesia or sedation, a critical patient safety issue. Current standard fasting protocols may be insufficient for GLP-1 RA users, necessitating modified strategies to mitigate this risk.

This systematic review synthesized clinical evidence on peri-procedural mitigation strategies for GLP-1 RA users. Researchers conducted a systematic search across PubMed, Embase, Cochrane CENTRAL, and Web of Science from inception to March 2026. Only original human studies were included, with secondary research excluded from qualitative synthesis. Due to substantial differences in study designs, populations, and outcome definitions, findings were synthesized narratively at the study level. The review analyzed 19 clinical studies and one administrative claims study separately, focusing on associations between modified fasting, medication withholding, and gastric point-of-care ultrasound (POCUS) with RGC reduction.

The review identified several strategies associated with reduced residual gastric content (RGC) in GLP-1 RA users. One retrospective study found that a 24-hour clear liquid diet was associated with significantly lower RGC, approximately 1-2% compared to 10% in controls, with an odds ratio (OR) of ≈ 0.13. Prospective ultrasound studies consistently showed that withholding weekly GLP-1 RAs for 7-8 days was associated with lower odds of high RGC when compared to shorter withholding intervals. Multiple studies also demonstrated that gastric POCUS, utilizing validated thresholds (>1.5 mL/kg or presence of solids), effectively identified patients at increased risk of elevated RGC. Aspiration events, while the ultimate clinical concern, were rare and inconsistently reported across the mitigation studies, making direct statistical analysis challenging. The administrative claims study, analyzed separately, provided additional observational context but was not combined with the clinical cohorts.

Extended GLP-1 RA withholding for 7-8 days reduced the odds of high RGC compared to shorter intervals, while a 24-hour clear liquid diet lowered RGC to 1-2% from 10% (OR ≈ 0.13).