Olanzapine reduces delirium symptoms in the critically ill pediatric patient

Delirium is a neuropsychiatric disorder characterized by acute disturbances in attention, consciousness, cognitive processing, perception, and the sleep-wake cycle. The few studies investigating treatment of delirium in critically ill children and adolescents have used differing diagnostic criteria, and have not employed control groups or procedures to blind observations. The objective of this study was to examine the efficacy of olanzapine for the treatment of delirium in the pediatric intensive care unit (ICU) using methodological procedures to reduce bias and allow greater generalization. Psychiatric records of 59 patients admitted to the pediatric ICU or cardiothoracic ICU over a 4 yr period with the diagnosis of delirium were examined. The delirium rating scale was used to assess delirium severity at the time of initial psychiatric evaluation and five days later. Raters were blinded to medication administration. Patients who were diagnosed with delirium, but did not receive olanzapine, or any other antipsychotic medication, served as the control group. Greater improvement of delirium symptoms was found for the olanzapine group (n = 31) than the control group (n = 28) (F _(1,40) = 4.86, r = 0.33, 95% confidence interval = 0.020-0.58). This finding remained statistically significant after controlling for initial delirium severity (F _{(1, 20)} = 28.62, r = 0.77, 95% confidence interval = 0.50-0.90). This study demonstrates patients with delirium administered olanzapine had greater reduction of delirium symptom severity than controls. It supplements the existing literature by using a study design that reduces expectancy effects and allows examination of the natural history of delirium symptoms without medication administration.