Why is Ozempic (semaglutide) contraindicated before surgery?

Ozempic (Semaglutide) Contraindications Before Surgery: Risk of Pulmonary Aspiration

Ozempic (semaglutide) is contraindicated before surgery due to its significant effect on delaying gastric emptying, which increases the risk of regurgitation and pulmonary aspiration during anesthesia, even in patients who have followed standard fasting guidelines. 1

Mechanism and Evidence

Glucagon-like peptide-1 (GLP-1) receptor agonists like semaglutide work by:

• Delaying gastric emptying
• Increasing satiety
• Suppressing appetite

This delayed gastric emptying creates a significant perioperative risk:

• Multiple case reports document regurgitation and pulmonary aspiration in patients taking semaglutide despite extended fasting periods (8-20 hours) 1, 2, 3
• Patients have required postoperative mechanical ventilation and ICU admission after aspiration events 1
• Endoscopic and tomographic evidence shows retained solid food in stomachs of patients who properly fasted 2, 4

Documented Cases of Aspiration

Several well-documented cases highlight this risk:

• Patient undergoing esophageal endoscopy had pulmonary aspiration despite 18 hours of fasting, requiring mechanical ventilation 1
• Patient undergoing breast lumpectomy regurgitated on induction despite 20 hours of fasting for solids 1, 3
• Patient undergoing hysteroscopy had large volume of undigested food suctioned despite appropriate fasting 1
• Patient undergoing renal nodule ablation had solid contents in stomach after 9 hours of fasting, discovered incidentally on CT 2

Current Guidelines

The most recent guidelines recommend:

1. For patients using GLP-1 RAs for weight loss:

   • Withhold medication for at least three half-lives before elective surgery 1, 5
   • For semaglutide, this means approximately 3 weeks before surgery 5

2. For patients using GLP-1 RAs for diabetes management:

   • Consult with the treating endocrinologist regarding risks/benefits of holding the medication 1
   • Consider the impact on glycemic control versus aspiration risk

Risk Mitigation Strategies

When GLP-1 RAs cannot be discontinued for sufficient time:

• Consider postponement of elective procedures 1
• Implement aspiration risk reduction strategies:
  • Rapid sequence induction
  • Pre-emptive gastric decompression in high-risk cases
  • Point-of-care gastric ultrasound to assess residual gastric contents 1
  • Consider prokinetic drugs pre-operatively (e.g., metoclopramide) 1, 5

Common Pitfalls

1. Assuming standard fasting is sufficient: Even with extended fasting of 18-20 hours, patients on semaglutide may still have significant gastric contents 1, 3

2. Failing to identify GLP-1 RA use: Patients may not disclose semaglutide use, especially when taken for weight loss rather than diabetes 2

3. Inadequate discontinuation time: Stopping semaglutide only a few days before surgery is insufficient due to its long half-life (approximately 1 week) 1, 3

4. Overlooking the risk in non-obese, non-diabetic patients: Cases have been reported in patients without traditional risk factors for aspiration 3

Conclusion

The risk of pulmonary aspiration in patients taking semaglutide is significant and occurs despite proper fasting. For elective procedures, withholding semaglutide for at least three half-lives (approximately 3 weeks) is recommended to reduce this risk, with special consideration for patients using it for diabetes management.