Preoperative ultrasound evaluation of gastric contents in children one hour after ingestion of clear liquid: An observational study

BACKGROUND: Gastric ultrasound is an effective, non-invasive method to assess the nature and volume of gastric content in the pediatric population. Recently, the UK, European, and French Pediatric Anesthesia Societies recommend fast for clear fluids in children for 1 h. However, studies showing that 1 h of fasting is safe in the pediatric population are still scarce. This study aims to verify by ultrasound evaluation if 1 h of fasting for clear liquids is sufficient to have an empty stomach before anesthetic induction. METHODOLOGY: Patients between 11 months and 16 years of age scheduled for elective outpatient surgery were included. A qualitative and quantitative ultrasound evaluation was performed by calculating the cross-sectional area (CSA) of the gastric antrum, 1 h after ingesting a volume of 3 mL/kg of a non-carbonated sports drink, before anesthetic induction. RESULTS: Fifty patients were included. The average CSA measured by ultrasound was 2.85 ± 1.64 cm(2) with an average calculated total volume of 12.9 ± 11.06 mL. All patients had an empty stomach criterion (calculated volume ≤1.5 mL/kg) during the ultrasound evaluation, with an average of 0.40 ± 0.23 mL/kg. With the qualitative assessment of gastric volume, 19 patients (38%) were classified as grade 0, 31 patients (62%) as grade 1, and none as grade 2. CONCLUSION: One hour of fasting after ingestion of 3 mL/kg of a non-carbonated sports drink is sufficient to meet ultrasound criteria for an empty stomach in a pediatric population undergoing elective outpatient surgery.