To systemically evaluate the preventive effect of haloperidol on delirium in critically ill patients and its safety.

The Medline, EMbase, Cochrane Library, VIP, CNKI and CBM databases were searched for randomized controlled trials (RCTs) about the preventive effect of haloperidol on delirium in critically ill patients published up to September 2018. Two reviewers independently screened literature according to inclusion and exclusion criteria, extracted data and assessed the methodological quality of included studies. Then meta-analysis was performed using RevMan 5.2 software.

Totally 4 RCTs involving 2 455 patients were included in this study. Meta-analysis showed that the 28-d delirium incidence [relative risk (RR) = 0.96, 95% confidence interval (CI) (0.65, 1.43), Z = 0.19, P = 0.85], delirium-free and coma-free days within 28 days [mean difference (MD) = 0.05, 95%CI (-0.06, 0.15), Z = 0.88, P = 0.38], 28-d survival rate [RR = 1.00, 95%CI (0.97, 1.04), Z = 0.23, P = 0.82] and ICU length of stay [MD = -0.18, 95%CI (-2.00, 1.64), Z = 0.20, P = 0.84] all showed no significant differences between the haloperidol group and control group. Moreover, there were no statistically significant differences in the QTc interval prolongation [RR = 1.18, 95%CI (0.83, 1.67), Z = 0.92, P = 0.36], extrapyramidal symptoms [RR = 1.07, 95%CI (0.69, 1.67), Z = 0.31, P = 0.76] and excessive sedation [RR = 1.90, 95%CI (0.77, 4.66), Z = 1.40, P = 0.16] between the two groups.

Haloperidol cannot prevent delirium in critically ill patients or improve their prognosis.