Safety and effectiveness of olanzapine and droperidol for chemical restraint for non-consenting adults: a systematic review and meta-analysis

Background: Chemical restraint (CR) is emergency drug management for acute behavioural disturbances in people with mental illness, provided with the aim of rapid calming and de-escalating potentially dangerous situations. Aims: To describe a systematic review of Randomised Controlled Trials (RCTs) reporting on short-term safety and effectiveness of drugs used for CR, administered to non-consenting adults with mental health conditions, who require emergency management of acute behavioural disturbances. A meta-analysis was conducted of those RCTs with comparable interventions, outcome measures and measurement timeframes. Method: Academic databases were searched for RCTs published between 1 January 1996 and 20th April 2020. Relevant RCTs were critically appraised using the 13-item JBI checklist. All RCTs were described, and step-wise filters were applied to identify studies suitable for meta-analysis. For these, forest and funnel plots were constructed, and Q and I² statistics guided interpretation of pooled findings, tested using MedCalc Version 19.1. Results: Of 23 relevant RCTs, 18 (78.2% total) had excellent methodological quality scores (at least 90%). Eight RCTs were potentially relevant for meta-analysis (six of excellent quality), reporting 20 drug arms in total. Adverse events for 6–36% patients were reported in all 20 drug arms. Four drug arms from two homogenous studies of N = 697 people were meta-analysed. These RCTs tested two antipsychotic drugs (droperidol, olanzapine) delivered intravenously in either 5 mgs or 10 mg doses, with outcomes of time to calm, percentage calm within five or 10 min, and adverse events. There were no significant differences between drug arms for either measure of calm. However, 5 mg olanzapine incurred significantly lower risk of adverse events than 10 mg olanzapine (OR 0.4 (95%CI 0.2−0.8)), although no dose differences were found for droperidol. Conclusion: 5 mg intravenous olanzapine is recommended for quick, safe emergency management of people with acute behavioural disturbances associated with mental illness.