Gastric emptying time of oral contrast material in children and adolescents undergoing abdominal computed tomography

Objectives: Considering the hazards of pulmonary aspiration of oral contrast material (OCM) during general anesthesia, we investigated the gastric emptying time (GET) of OCM in children and adolescents undergoing abdominal computed tomography (CT). Patients and Methods: Included in the study were 101 consecutive patients ages 3.1 to 17.9 years (mean age 12.2 ± 3.3 years), who underwent contrast-enhanced abdominal CT for suspected acute appendicitis (n = 90), abdominal trauma (n = 10), or suspected ileus (n = 1). Oral iodinated ioxithalamate was given for bowel opacification. Background data (age, sex, weight, chronic diseases, and medication intake), time of initiation and completion of OCM, and time of CT scanning were recorded. To estimate the GET of OCM, CT images were reviewed to examine whether the stomach was empty or full of OCM at the time of imaging. Results: The Kaplan-Meier curve showed that 75% of the patients had OCM in the stomach 48 ± 5.2 minutes after its completion, 50% after 74 ± 7.9 minutes, and 25% after 135 ± 32.5 minutes; 1 patient still had OCM after 162 minutes. Except for the length of time taken to drink the contrast material (≤90 minutes was associated with slower empting of the stomach; log rank, P = 0.03), GET of OCM was not correlated with sex (P = 0.16), age (P = 0.15), weight (P = 0.13), or type of diagnosis (P = 0.41). Conclusions: Given the variability of GET of OCM and if clinically feasible, we advocate waiting at least 3 hours between completion of OCM ingestion and general anesthesia induction.