Prolonged recovery and delayed side effects of sedation for diagnostic imaging studies in children

Although sedation-related adverse events in children in the hospital setting have been extensively reported, limited data are available regarding adverse events after discharge home. Despite nationally recommended discharge criteria, in busy outpatient settings, children may be sent home into the care of their parents after a brief recovery from sedation, placing them at risk for adverse events in an unmonitored setting. Previous studies have not addressed issues such as requirement for escalation of care after discharge (ie, emergency department visits or hospitalization), or parental satisfaction with their child's sedation experience. This study was undertaken to evaluate the recovery and delayed adverse events after discharge of children who received sedation for magnetic resonance imaging or computed tomography.

With approval from the institutional review board and written informed consent from a parent, children (<18 years old) sedated for magnetic resonance imaging or computerized tomography were studied. Sedative drugs were ordered at the discretion of the radiologist responsible for the procedure in accordance with institutional sedation guidelines and in consideration of the child's health status. Pediatric nurses in the diagnostic areas administered the sedative agent(s) and monitored children according to preestablished institutional guidelines. Demographics, sedative(s) administered, and adverse events including hypoxemia (decrease in SpO(2) by >/=10% of baseline) and sedation events such as inadequate, failed, or excessive sedation, were documented on the institutional quality assurance tool. Children were discharged from the hospital when they met the following preestablished discharge criteria: return to baseline vital signs, level of consciousness close to baseline, and the ability to maintain a patent airway. The following day, parents were telephoned and questioned regarding the child's alertness, side effects, and whether medical follow-up had been sought. Parents also rated their overall satisfaction with the sedation experience.

Three hundred seventy six children comprised the sample. Eighty nine percent of children received chloral hydrate (CH; 64 +/- 13 mg/kg), and 11% midazolam (.15 +/-.13 mg/kg) as the primary sedative. There was an 8% incidence of failed sedation, and a 1.6% incidence of hypoxemia during the procedure. Three children required prolonged monitoring in the postanesthesia care unit before discharge; 1 child attributable to an allergic reaction, a second attributable to wheezing and oxygen desaturation, and the third attributable to prolonged sedation from CH and midazolam. These children were discharged home from the postanesthesia care unit without additional sequelae. Side effects after discharge included: motor imbalance (31%), gastrointestinal effects (23%), agitation (19%), and restlessness (14%). Agitation and restlessness lasted greater than 6 hours in more than one third of children who experienced these effects. CH was more commonly associated with imbalance compared with midazolam, and restlessness and prolonged imbalance were associated with younger age. Medical advice was sought after discharge for 15 (4%) children, 3 of whom required a visit to the emergency department for excessive or prolonged sedation. Each of these children had received CH as a sole sedative in recommended doses (61-77 mg/kg). In 1 of these cases, the procedure had been aborted because of inadequate sedation in the hospital, yet the child became difficult to arouse at home. Only 48% of children returned to baseline activity and behavior within 8 hours of the procedure; however, 89% were back to baseline status within 24 hours. Notably, 5% of all children did not return to baseline activity until the second day after the procedure. Although not statistically significant, infants <12 months old experienced delayed recovery (ie, >/=24 hours) more frequently compared with older c