GLP-1 Agonists and Surgical Fasting: Is a 24-Hour Liquid Diet Safer?

Patients taking GLP-1/GIP receptor agonists (like Ozempic or Mounjaro) often experience delayed gastric emptying, which can lead to gastric retention. This poses a significant risk of pulmonary aspiration during surgery, where stomach contents are inhaled into the lungs. Current ASA (American Society of Anesthesiologists) fasting guidelines may not adequately account for this delayed emptying in patients on these medications. This study addresses the crucial question of whether standard fasting guidelines are sufficient for patients on GLP-1/GIP agonists undergoing surgery, or if extended fasting is necessary.

This observational study aims to assess the non-inferiority of standard ASA fasting guidelines compared to a 24-hour clear liquid diet in patients on GLP-1/GIP medications. The primary objective is to measure and compare the volume of retained gastric contents using gastric ultrasound in two distinct patient groups. Researchers hypothesize that patients following standard fasting protocols (e.g., 8 hours nothing by mouth) might exhibit higher gastric volumes, potentially increasing the risk of pulmonary aspiration during surgery. The study's core aim is to determine if standard fasting practices result in gastric volumes that are statistically comparable (non-inferior) to those achieved with a more extended 24-hour clear liquid diet in this specific patient population.