Thirteen RCTs were included in the review (n=1,305). Study quality was variable: six studies had a Jadad score of 5, three studies had a score of 4, three studies had a score of 2 and one study scored 1.
Management of delirium (four RCTs, 158 patients): Comparison of first- or second-generation antipsychotics suggested little difference between the groups in reduction of delirium severity, length of delirium or adverse events. Frequency of response was described as high for all treatment groups (75% had Memorial Delirium Assessment Scale scores less than 13, 80% of patients had 50% reduction in Delirium Rating Scale-R-98). One study compared haloperidol, chlorpromazine and lorazepam and noted significant differences in adverse events (sedation and confusion) associated with the lorazepam arm.
Prevention of delirium (nine RCTs, 1,147 patients): One study showed a reduction in delirium severity, duration and hospital length of stay with low-dose haloperidol compared to placebo in patients at high risk of developing delirium. Three studies examined cholinergic enhancement using donepezil or citicoline and found no benefit over placebo. A comparison of dexmedetomidine with lorazepam used as sedatives in ventilated patients in intensive care unit showed no difference in incidence of delirium. Use of nitrous oxide in inhalational anaesthesia was not associated with any significant difference in delirium outcome.