Glp1 Perioperative Aspiration

---
name: glp1-perioperative-aspiration
description: Guide perioperative decisions for patients on GLP-1 receptor agonists (semaglutide, tirzepatide, liraglutide, dulaglutide) undergoing general anesthesia, deep sedation, or endoscopy — whether to hold, how long, and how to weigh aspiration risk from delayed gastric emptying. Use when a clinician asks "hold Ozempic/Wegovy/Mounjaro before surgery", "GLP-1 before endoscopy", "anesthesia aspiration risk tirzepatide", or needs a pre-procedure decision for a patient on a long-acting GLP-1 RA. Grounded in Mounjaro and Wegovy Canadian Product Monographs and ASA/multisociety guidance.
---

# GLP-1 RA — Perioperative & Pre-Procedure Aspiration Risk

## Purpose

Long-acting GLP-1 RAs delay gastric emptying, raising the risk of pulmonary aspiration during general anesthesia, deep sedation, and endoscopy. This skill turns the monograph warning into a bedside hold/proceed decision.

## Activation

Trigger when:
- Patient on GLP-1 RA is scheduled for surgery, GA, deep sedation, or endoscopy.
- Clinician asks when to hold, whether to hold, or how long to hold.
- Pre-op anesthesia assessment.

## Half-Life Reference (drives hold duration)

| Agent | Half-life | Dosing |
|---|---|---|
| Tirzepatide (Mounjaro) | ~5 days | weekly |
| Semaglutide (Ozempic/Wegovy/Rybelsus) | ~1 week | weekly (oral: daily) |
| Dulaglutide (Trulicity) | ~5 days | weekly |
| Liraglutide (Victoza/Saxenda) | ~13 h | daily |
| Exenatide ER | ~2 weeks | weekly |
| Lixisenatide (Lyxumia) | ~3 h | daily |

## Decision Matrix

### Elective surgery / GA / deep sedation

| Agent class | Hold before procedure |
|---|---|
| Weekly GLP-1 RA (semaglutide, tirzepatide, dulaglutide, exenatide ER) | **Skip the dose in the week of the procedure** (≥ 1 week hold) |
| Daily GLP-1 RA (liraglutide, lixisenatide, oral semaglutide) | **Hold on day of procedure** |

### Endoscopy / upper GI procedures

- Same hold schedule as above.
- If proceeding without hold → treat as **full stomach**: rapid-sequence induction, aspiration precautions, consider clear fluid fast ≥ 8 h instead of usual 2 h.
- If GI symptoms present (nausea, bloating, retained food sensation) → **delay** procedure or convert to full-stomach precautions.

### Emergency / urgent surgery

- Do NOT delay lifesaving procedure.
- Manage as **full stomach**: RSI, cricoid pressure per local protocol, consider gastric decompression, aspiration prophylaxis.

## Pre-Procedure Checklist

1. Confirm last GLP-1 dose date and agent.
2. Ask about **current GI symptoms** — nausea, early satiety, retained-food sensation, recent vomiting.
3. Consent: explicitly include aspiration risk in the GA/sedation consent for GLP-1 RA patients.
4. Communicate to anesthesia team — flag the patient as on a GLP-1 RA.
5. Confirm clear liquid fast: at minimum 2 h (standard); extend to ≥ 8 h if dose not held.

## Restart Rule

- Resume the weekly GLP-1 RA on the next scheduled weekly day post-procedure, provided:
  - No ongoing vomiting.
  - Oral intake established.
  - No active pancreatitis or ileus.
- For daily agents: resume when eating normally.

## Special Case — Pre-Endoscopy in Symptomatic Patients

If on GLP-1 RA **and** symptomatic (reflux, nausea, vomiting) → see `glp1-endoscopy-pre-procedure` for the full proceed/delay/modify algorithm.

## Label Quotes

- **Mounjaro:** "Pulmonary aspiration has been reported in patients receiving long-acting GLP-1 receptor agonists undergoing general anesthesia or deep sedation. For the safe management of patients, consider the benefits and risks, and advise patients of these, prior to such procedures." (§7, Perioperative considerations)
- **Wegovy:** Delayed gastric emptying is listed as a warning. Events of intestinal obstruction and ileus reported post-market.

## Rules & Constraints

1. **Don't cancel emergency surgery to wait for drug washout** — manage as full stomach.
2. **Symptom screen beats time-since-dose** — a symptomatic patient at 2 weeks still has retained content risk.
3. **Communicate** — anesthesia MUST be informed; surprises in induction are preventable harms.
4. **Document consent** mentioning aspiration risk.
5. **Local protocols vary** — defer to institutional GLP-1 perioperative policy if present.

## Reference

- MOUNJARO Product Monograph, Eli Lilly Canada, §7 Perioperative considerations.
- WEGOVY Product Monograph, Novo Nordisk Canada, §7 Gastrointestinal.
- ASA Consensus-Based Guidance on Preoperative Management of Patients on GLP-1 RAs (2023).