The usefulness of non-contrast abdominal computed tomography for detection of residual drugs in the stomach of patients with acute drug overdose.

Objectives: If clinicians can know that there are many life-threatening drugs left in the stomach through a non-invasive method over 60 min after drugs ingestion, it may be preferable to minimize absorption of remnant drugs through various methods according to the characteristic of the drug. Computed tomography (CT) has gained wide acceptance in the detection of drug mules. Therefore, we evaluated the prevalence of drugs in the gastric lumen using abdominal non-contrast CT, performed over 60 min after acute drug poisoning. Materials and methods: This was a prospective cohort study of patients with acute drug poisoning who were admitted to the emergency department (ED) between March 2017 and February 2018. If the patient visited the ED over 60 min after ingestion of life-threatening or unknown drugs, non-contrast CT scan was performed. "Presence of drugs" was defined in the non-contrast CT as a round-shaped lesion with higher density than the gastric mucosa. In addition, "positive radiodense image" was defined as that with higher density than the gastric mucosa regardless of drug appearance in the non-contrast CT scan. Results: Among a total of 482 patients with drug poisoning, 140 were finally included in the study. Residual drugs were detected in 36 patients (25.7%). Further, regardless of the presence of drugs, 58 patients (41.4%) showed positive radiodense image in the stomach. The median Hounsfield unit of drugs was 131.5 and that of food materials in the stomach was 34.5. Total duration of hospital stay was significantly longer in the "absence of drug" group and sustained-release drugs were detected more frequently in the "presence of drugs" group. Conclusions: Detection rate of drugs and presence of positive radiodense image, regardless of drug appearance, were as high as 25.7% and 41.4%, respectively. Sustained-release drugs were detected more frequently in the "presence of drugs" group.