Sedation of neurologically impaired children undergoing MRI: a sequential approach

Background: The purpose of this retrospective study was to determine the efficacy of a sequential approach meant to rescue failed chloral hydrate sedation and to obtain a low rate of adverse events along with predictable timings in neurologically impaired children undergoing magnetic resonance imaging. Methods: We retrospectively evaluated 1104 chloral hydrate sedations performed between 2002 and 2004 on 862 children weighing < 26 kg. If the desired sedation score Q on the Skeie Scale) was not reached within 30 min after oral administration of chloral hydrate, sedation was considered as potentially failed, and supplementation with sevoflurane, i.m. or i.v. ketamine, and i.v. pentobarbital and midazolam was started. Results: Twenty-seven sessions failed because of excessive movement. Mean induction time was significantly higher for patients who received supplementation (52.2 min vs 39.1 min), while no differences in recovery and total sedation times were found. Supplementation significantly increased the incidence of respiratory obstruction (4.6% vs 2.4%), although the incidence of other adverse events was unaffected. Conclusions: Administering up to 1.5 g of chloral hydrate without supplementation was associated with a failure rate of approximately 20%, but the proposed sequential approach enabled us to rescue the majority of failed sedations while maintaining an acceptably low incidence of adverse events.