Ultrasound assessment of the effects of three different fasting regimens of clear fluids on gastric fluid volume in children.

Abstract

Background: Two-hour minimum fasting policy for clear fluids before surgery may prolong fasting and cause negative experiences for children. One-hour minimum and/or liberal fasting policies for clear fluids can significantly shorten the fasting time. However, their effectiveness and safety remain inadequately validated. This study investigated the effects of the above three regimens on the gastric fluid volume (GFV) before anesthesia induction in children.

Methods: This prospective randomized controlled trial involved 147 children (1-13 years old, ASA I or II) undergoing elective tonsillectomy and adenoidectomy and were randomly allocated to three groups: Group 2: fasting clear fluids for a minimum of 2 h, Group 1: fasting clear fluids for a minimum of 1 h, and Group 0: liberal fluid fasting. Water intake was measured within 6 h before surgery. The primary outcome was GFV before anesthesia induction. Secondary outcomes included water intake behavior and adverse events.

Results: Among the three groups, there was no evidence for differences in GFVs. The total water intake volume within 6 h before surgery was 80.0 (IQR: 40.0-160.0) mL for Group 2, 150.0 (IQR: 72.5-300.0) mL for Group 1, and 85.0 (IQR: 40.0-180.0) mL for Group 0. The total number of water intake episodes was 1.0 (1.0-2.5), 2.5 (1.0-4.0), and 2.0 (1.0-3.0) for Group 2/1/0, respectively. The last water intake volume before surgery in Group 2/1/0 was 60 (IQR: 30-100) mL, 60 (IQR: 30-100) mL, and 40 (IQR: 20-60) mL, respectively. There were no increases in adverse events among groups.

Conclusion: Compared to fasting with clear fluids for 2 h, the 1-h and liberal fluid fasting regimens do not increase GFV in children before induction.

Trial registration: This prospective randomized controlled trial was registered at the Chinese Clinical Trial Registration (No. ChiCTR2300078309; Date: December 5, 2023).