Preoperative gastric ultrasound in children with cerebral palsy: a cross-sectional observational study

Pulmonary aspiration during anesthesia, though rare, can be catastrophic. Gastric ultrasound provides an objective assessment of gastric contents and may be particularly relevant for children with Cerebral Palsy (CP), who are at risk of delayed gastric emptying.

We conducted a cross-sectional study in a pediatric hospital including children scheduled for elective surgery per ASA fasting guidelines. Preoperative gastric ultrasound measured antral CSA in right lateral decubitus, and gastric volume was estimated using the Perlas formula. Fasting time, medication use, and clinical data were recorded. Group comparisons used Wilcoxon, Fisher's exact, or Chi-Square tests; multiple linear regression adjusted for confounders.

Sixty-two children were studied: 30 with Cerebral Palsy (CP) and 32 controls. No patient exceeded the high-risk gastric volume threshold (1.5 mL.kg^-1) and no surgeries were cancelled. CP patients had shorter fasting times (6.5 vs. 8.0 h; p < 0.001) and higher medication use (47% vs. 6.3%; p < 0.001). Gastric CSA (4.0 vs. 3.0 cm²; p < 0.001) and estimated gastric volume per kg (0.7 vs. 0.4 mL.kg^-1; p < 0.001) were greater in CP. Multivariable models showed attenuation, but quantile regression confirmed higher lower CSA (+1.25 cm²; p = 0.007). Excluding medication users, CP remained associated with greater gastric volume.

Children with cerebral palsy exhibit larger CSA and higher gastric volumes despite adequate fasting. Although clinically safe, these findings support the role of gastric ultrasound in preoperative risk assessment for this vulnerable group.