What are the latest recommendations for managing Glucagon-like peptide-1 (GLP-1) receptor agonists, such as liraglutide (Victoza) and semaglutide (Ozempic), in patients undergoing anesthesia and surgery?

Latest Recommendations for GLP-1 Receptor Agonists and Anesthesia

Primary Recommendation

For patients taking GLP-1 receptor agonists undergoing elective surgery, hold the medication for at least three half-lives before the procedure (approximately 3 weeks for weekly semaglutide, 3 days for daily liraglutide) to minimize aspiration risk, with specific management strategies based on whether this timeline can be achieved. 1, 2

Preoperative Assessment and Documentation

Before any procedure requiring anesthesia or deep sedation, document the following 1:

• Specific GLP-1 agent, dose, and indication (diabetes vs. weight loss)
• Date commenced, last dose taken, and any recent dose changes
• Presence of gastrointestinal symptoms (nausea, vomiting, abdominal distention)
• Concomitant medications that delay gastric emptying (opioids, proton pump inhibitors, tricyclic antidepressants)
• Recent recreational drug use (alcohol, cannabis) that affects gastric motility

Medication Holding Periods by Half-Life

The three half-life rule clears approximately 88% of the drug from the system 1:

• Weekly agents (semaglutide/Ozempic): Hold for 3 weeks (approximately 21 days) 2
• Daily agents (liraglutide/Victoza): Hold for 3 days 1

Management Based on Indication

For Weight Loss Patients

Hold GLP-1 receptor agonists for at least three half-lives before elective procedures without exception, as the risks of continuing outweigh benefits in this population 1, 2

For Diabetes Patients

Consult with the treating endocrinologist to weigh glycemic control benefits against aspiration risk 1, 2. This consultation should address:

• Risks and benefits of holding the drug for three half-lives
• Bridging diabetic therapy recommendations if the GLP-1 agent must be held longer than the next scheduled dose 1

Risk Stratification and High-Risk Scenarios

Consider patients at high risk for retained gastric contents if they have 1, 2:

• Unable to hold medication for three half-lives before the procedure
• Recently started the medication or increased dose (within 12 weeks)
• Active gastrointestinal symptoms (nausea, vomiting, abdominal distention)

Aspiration Risk Reduction Strategies

For High-Risk Patients

Implement the following evidence-based interventions 1, 2:

1. Preprocedural diet modification: 24-hour clear fluid diet followed by standard 6-hour fasting 3

2. Prokinetic medication: Administer metoclopramide or erythromycin preoperatively 1, 2

3. Point-of-care gastric ultrasound: Assess for residual gastric contents (volume >1.5 ml/kg indicates high risk) 1, 2

4. Rapid sequence intubation: Use this technique to reduce aspiration risk during induction 1, 2

5. Pre-emptive gastric decompression: Consider in very high-risk patients 1

6. Procedure postponement: Reschedule elective cases when possible to allow adequate drug clearance 1

Standard Fasting Times

Standard preoperative fasting times (6 hours for solids, 2 hours for clear liquids) are insufficient for patients on GLP-1 receptor agonists, even after proper fasting, due to delayed gastric emptying 2, 4. The 24-hour clear fluid diet is now recommended 3.

Day of Procedure Algorithm

On the day of surgery, follow this decision pathway 1:

• If GLP-1 withheld for three half-lives AND no high-risk features: Perform gastric ultrasound

  • If gastric volume <1.5 ml/kg with no solid matter: Proceed with standard anesthetic technique
  • If gastric volume >1.5 ml/kg or solids present: Treat as high-risk (see below)

• If GLP-1 NOT withheld for three half-lives OR high-risk features present:

  • Administer prokinetic medication
  • Perform gastric ultrasound
  • Use rapid sequence intubation
  • Consider delaying procedure

Evidence Quality and Controversies

The recommendation to hold GLP-1 agents represents a significant shift from earlier guidance 5. Prior to 2023, guidelines recommended continuing these medications perioperatively 1. This change was driven by:

• Case reports of aspiration events despite proper fasting 2
• Endoscopic evidence of retained gastric contents in patients on GLP-1 agents 1
• FDA acknowledgment that available data are insufficient to inform specific recommendations, but pulmonary aspiration has been reported 4

However, one large retrospective study found no increased risk of perioperative complications in GLP-1 users compared to non-users 6. Despite this, the preponderance of mechanistic evidence (delayed gastric emptying) and case reports supports a cautious approach 1, 2.

The Australian/New Zealand 2025 guidelines diverge slightly, recommending continuation of GLP-1 agents with 24-hour clear fluid diet modification rather than cessation 3. However, the three half-life cessation approach from the Anaesthesia journal guidelines represents the most conservative and widely adopted international standard 1, 2.

Critical Pitfalls to Avoid

• Do not rely on absence of gastrointestinal symptoms to rule out retained gastric contents; aspiration has occurred in asymptomatic patients 2, 3
• Do not assume standard fasting times are adequate even if the medication was held for only 1 week (the older ASA recommendation) 2
• Do not forget to inform patients preoperatively to notify healthcare providers about GLP-1 use before any planned procedures 4
• Do not discontinue GLP-1 agents in diabetic patients without endocrinology consultation regarding bridging therapy 1, 2

Shared Decision-Making

Use a transparent discussion approach with patients to explain the aspiration risk, the rationale for holding medications, and alternative management strategies, allowing informed consent for the chosen approach 1.