Effect of Preemptive Acetaminophen Administered Within 1 Hour of General Anesthesia on Gastric Residual Volume and pH in Children

Purpose Determine whether preoperative oral acetaminophen increases gastric residual volume and lowers gastric pH. Design Prospective, randomized. Methods Healthy children, 1 to 14 years, having elective magnetic resonance imaging (MRI) were randomized to oral acetaminophen within 1 hour of induction versus fasting. Gastric volume and pH were measured immediately after intubation. Adverse events were documented from induction through 72 hours post MRI. Findings Thirty-seven children completed the study (16 treatment, 21 control). Gastric residual volume between groups was not significantly different. The acetaminophen group had significantly higher pH than control group (1.86 ± 0.42 vs 1.56 ± 0.34; P ≤ .044). Three children in the control and 6 in the treatment group experienced minor adverse events. Conclusions Findings suggest administering oral acetaminophen prior to induction of anesthesia is not associated with increased gastric residual volume and increases the gastric pH. Further study is needed to examine outcomes such as aspiration pneumonitis risk.