Sedation for children undergoing magnetic resonance imaging : efficacy and safety of rectal thiopental

The need to reappraise sedation policy is dictated by newer noninvasive imaging modalities. In this study we evaluate the safety and efficacy of rectally-administered thiopental in children undergoing MRI. Eighty-three consecutive patients with congenital heart disease (mean age 2.9 years, SD 2.5) undergoing MRI evaluation of the heart were given thiopental (25-50 mg/kg, 700 mg max) per rectum. In order to prevent leakage, a female urinary catheter was used. In 79 patients (95.2%) successful sedation was achieved and adequate MR imaging could be obtained. In 4 patients (4.8%) the sedation was inadequate. Respiratory depression was not encountered in any of the patients. The presence of cyanotic congenital heart disease in 26 patients had no influence on the safety and efficacy of thiopental. All successfully sedated children were asleep within 30 min and adequate sedation was maintained for at least 45 min. All patients could be aroused within 90 min, and sent home thereafter. Minor side-effects occurred in two patients. Rectally-administered thiopental is a safe and effective sedative drug with a duration of action tailored to performing MRI.