What are the preoperative recommendations for patients taking Glucagon-like peptide-1 (GLP-1) receptor agonists, such as liraglutide (Victoza), prior to conscious sedation?

Preoperative Recommendations for Patients on GLP-1 Receptor Agonists Before Conscious Sedation

For patients taking GLP-1 receptor agonists, withhold the medication for at least three half-lives before conscious sedation procedures to reduce aspiration risk. 1

Risk Assessment

• GLP-1 receptor agonists significantly delay gastric emptying, increasing the risk of regurgitation and pulmonary aspiration during procedures involving sedation, even with proper fasting 2, 3
• Multiple case reports document aspiration in patients on GLP-1 agonists despite appropriate fasting periods 2, 3
• The FDA label for liraglutide specifically warns that it "may cause their stomach to empty more slowly which may lead to complications with anesthesia or deep sedation during planned surgeries or procedures" 4

Medication-Specific Recommendations

• For daily GLP-1 agonists (e.g., liraglutide with 13-hour half-life): withhold for at least 39 hours (3 half-lives) before the procedure 1, 3
• For weekly GLP-1 agonists:
  • Semaglutide (7-day half-life): withhold for 3 weeks before the procedure 2, 3
  • Dulaglutide (4.5-4.7 day half-life): withhold for approximately 2 weeks before the procedure 3

Special Considerations Based on Indication

• For patients taking GLP-1 agonists for weight loss: withhold for at least three half-lives before the procedure 1, 2
• For patients taking GLP-1 agonists for diabetes: consult with the treating endocrinologist regarding:
  • Risks and benefits of holding the drug for at least three half-lives 1
  • Recommendations for bridging diabetic therapy if the GLP-1 receptor agonist is to be held 1, 2

Risk Mitigation Strategies if Unable to Withhold for Three Half-Lives

If the procedure cannot be postponed until three half-lives have passed:

1. Document thoroughly:

   • Indication and dose of GLP-1 receptor agonist
   • Date drug commenced, dose variations, last dose taken
   • Symptoms of nausea, vomiting or abdominal distention
   • Co-prescribed drugs that can delay gastric emptying 1

2. Implement risk reduction strategies:

   • Consider prokinetic drugs such as metoclopramide or erythromycin pre-operatively 1, 3
   • Use point-of-care gastric ultrasound to assess residual gastric contents 1, 3
   • Consider rapid sequence intubation instead of conscious sedation 1
   • Recommend clear fluid diet for 24 hours before pre-operative fasting 5

Common Pitfalls and Caveats

• Standard fasting guidelines are insufficient for patients on GLP-1 agonists, as case reports show aspiration despite extended fasting periods 3
• The American Society of Anesthesiologists recommends withholding weekly-dose GLP-1 therapy for the week prior to elective procedures, but emerging evidence suggests this may be insufficient 2, 6
• Assuming shorter-acting daily GLP-1 preparations carry the same risk as weekly preparations is incorrect; risk varies depending on the specific agent 3
• Underestimating aspiration risk with "light" sedation is a common pitfall, as even conscious sedation impairs protective reflexes 3

Decision Algorithm

1. Identify which GLP-1 agent the patient is taking and calculate three half-lives
2. If unable to postpone until three half-lives have passed:
   • For weight loss indication: strongly recommend postponement
   • For diabetes indication: consult with treating endocrinologist
3. If proceeding with procedure before three half-lives:
   • Consider pure local anesthesia without sedation if possible
   • Implement all aspiration risk reduction strategies
   • Treat as a "full stomach" case 6