Important Anesthesia Recommendations About Weight-loss Drugs

A brief, important follow-up about a drug class that is seeing wider use

Important Anesthesia Recommendations About Weight-loss Drugs

Two weeks ago, CORRelations covered findings from an authoritative randomized, double-blind “withdrawal trial” evaluating what happens when patients stop taking tirzepatide (Mounjaro). While the drug resulted in about 21% weight loss over the 36-week opening span of the study, patients regained an average of two-thirds of the weight they lost upon discontinuation of the medication. That finding has been fairly consistent among other drugs in that class, including semaglutide (Wegovy, Ozempic).

This post spurred a CORRelations reader to point out that there are current American Society of Anesthesiologists (ASA) guidelines for the perioperative management of patients taking these medications. While these are from another specialty and were first published last year, they have newfound relevance to readers here.

These guidelines are freely available in full-text form. While the evidence they muster mainly comes from case reports pertaining to instances of delayed gastric emptying that could cause regurgitation and pulmonary aspiration of gastric contents, it’s imperative that we ask our patients whether they are taking weight-loss drugs.

The main recommendations:

Prior to the Procedure:

  • For patients on daily dosing of these medications, consider holding them on the day of surgery, and for those on weekly dosing consider holding them a week prior to the procedure, regardless of indication (type 2 diabetes or weight loss), dose, or the type of procedure/surgery.
  • For patients with diabetes, if the drug is to be held for longer than that, consider consulting an endocrinologist for glycemic management.

Day of the Procedure: 

  • If the patient has GI symptoms, consider delaying the elective procedure because of the risk of regurgitation and aspiration.
  • If the patient has no GI symptoms, but the GLP-1 agonists were not held as advised, either proceed with “full stomach” precautions or evaluate gastric volume by ultrasound. If the stomach is empty, proceed with surgery; if the stomach is full or if ultrasound is inconclusive or not possible, consider delaying the procedure or apply “full stomach” precautions, but the risk of regurgitation and aspiration may be elevated.
  • Follow the current ASA fasting guidelines, though they acknowledge there is no evidence on this point vis-a-vis the new weight-loss drugs.


Joshi GP, Abdelmalak BB, Weigel WA, et al. American Society of Anesthesiologists Consensus-Based Guidance on Preoperative Management of Patients (Adults and Children) on Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists. ASA News. June 29, 2023.