What are the preoperative (preop) management recommendations for patients on Glucagon-like peptide-1 (GLP-1) receptor agonists, such as exenatide (Byetta) or liraglutide (Victoza), undergoing surgery?

Preoperative Management of GLP-1 Receptor Agonists

For patients on GLP-1 receptor agonists undergoing surgery, these medications should be held for at least three half-lives before the procedure to reduce the risk of pulmonary aspiration due to delayed gastric emptying. 1

Risk Assessment

• GLP-1 receptor agonists significantly delay gastric emptying, increasing the risk of regurgitation and pulmonary aspiration during procedures involving sedation or general anesthesia 1
• Multiple case reports document regurgitation and pulmonary aspiration in patients on GLP-1 agonists despite appropriate fasting periods 2
• FDA drug labels for exenatide and liraglutide specifically warn about pulmonary aspiration risk during general anesthesia or deep sedation due to delayed gastric emptying 3, 4

Preoperative Recommendations by Indication

For Weight Loss Patients

• Hold GLP-1 receptor agonist for at least three half-lives before the procedure (approximately 88% drug clearance) 1
• For semaglutide (weekly), this means holding for 3 weeks before surgery 1
• For dulaglutide (weekly), hold for approximately 2 weeks 2
• For daily preparations like liraglutide, hold for approximately 39 hours (3 half-lives of 13 hours) 2, 5

For Diabetes Patients

• Consult with the treating endocrinologist regarding: 1
  • Risks and benefits of holding the drug for at least three half-lives
  • Recommendations for bridging diabetic therapy if the GLP-1 receptor agonist will be held longer than the next scheduled dosing time
• Balance the risk of aspiration against the benefit of perioperative glycemic control 1, 6

High-Risk Patient Assessment

Identify patients at higher risk for aspiration: 1

• Those unable to hold the GLP-1 receptor agonist for three half-lives before the procedure
• Those who have recently started the medication or increased their dose
• Those experiencing nausea, vomiting or abdominal distention
• Patients taking other medications that delay gastric emptying (opioids, proton pump inhibitors, tricyclic antidepressants)
• Recent intake of recreational drugs that can delay gastric emptying (alcohol, cannabis)
• Previous gastro-oesophageal surgery

Risk Mitigation Strategies

For high-risk patients or when the procedure cannot be delayed: 1

• Consider prokinetic drugs such as metoclopramide or erythromycin pre-operatively
• Use point-of-care gastric ultrasound to assess residual gastric contents
• Consider rapid-sequence intubation to reduce the risk of pulmonary aspiration
• In very high-risk patients, consider pre-emptive gastric decompression
• Consider postponement and rescheduling of elective procedures
• Recommend clear fluid diet for some period before pre-operative fasting

Day of Procedure Algorithm

If GLP-1 receptor agonist was NOT withheld for three half-lives: 1

1. Consider prokinetic drug administration
2. Perform gastric ultrasonography
3. If significant gastric contents are present, consider rapid sequence intubation

If GLP-1 receptor agonist WAS withheld for three half-lives: 1

1. Proceed with standard anesthetic approach if gastric volume is <1.5 ml/kg
2. Consider delaying procedure if gastric volume exceeds this threshold

Common Pitfalls to Avoid

• Relying solely on standard fasting guidelines is insufficient for patients on GLP-1 agonists 2
• Assuming that shorter-acting daily GLP-1 preparations carry the same risk as weekly preparations 5
• Underestimating the aspiration risk with "light" sedation, which still impairs protective reflexes 2
• Failing to instruct patients to inform healthcare providers about their GLP-1 receptor agonist use prior to any planned surgeries or procedures 3, 4
• Discontinuing long-acting GLP-1 drugs for only 7 days, which is insufficient to ensure an empty stomach pre-operatively 1

The management of patients on GLP-1 receptor agonists in the perioperative period requires careful consideration of both the risks of aspiration and the benefits of glycemic control, with a shared decision-making approach between the patient, surgeon, anesthesiologist, and endocrinologist when appropriate 1, 6.