As millions of patients on semaglutide, tirzepatide, and related agents enter operating rooms worldwide, anesthesiologists face a genuine clinical dilemma that standard fasting protocols were never designed to address. The pharmacology of GLP-1 receptor agonists fundamentally alters the gastric emptying timeline, and the surgical community is now catching up to that reality.
This narrative review synthesizes mechanistic data, clinical investigations, and case reports to characterize the aspiration risk landscape for GLP-1-treated surgical patients. The central finding is that GLP-1-based therapies reliably impair solid-phase gastric emptying — an effect most pronounced during the early treatment period and dose escalation phases — and that this impairment can persist even after standard preoperative fasting intervals and short-term drug interruption. While overt aspiration events remain relatively rare in published series, multiple perioperative case reports have documented unexpected solid gastric residue at anesthesia induction, a scenario that standard nil-per-os guidelines do not anticipate. The review also notes that dual agonists combining GIP and GLP-1 activity appear to share these gastric motility effects.
The clinical guidance landscape has shifted meaningfully in a short period. Earlier consensus leaned toward routine preoperative drug discontinuation, but more recent multisociety positions favor continuation in most asymptomatic patients, supplemented by enhanced mitigation: modified preoperative dietary patterns, strict fasting enforcement, selective point-of-care gastric ultrasound, preference for regional anesthesia where feasible, and individualized airway strategy. This represents an important pivot from population-wide drug interruption — which carries its own metabolic risks for diabetic and obese patients — toward stratified, patient-specific risk assessment.
From a broader evidence standpoint, this review is a narrative rather than a systematic meta-analysis, which limits its ability to quantify absolute risk. The available clinical literature remains dominated by small cohorts and case reports rather than prospective controlled trials. Still, the convergence of mechanistic plausibility and clinical signals makes the gastric emptying concern credible and actionable. For health-conscious adults planning elective procedures while on GLP-1 therapy, this review signals that transparent communication with the surgical and anesthesia team about medication timing is increasingly consequential — and that protocols are actively evolving.