Objective
To investigate the effect of early versus late versus no antipsychotic administration on intensive care unit (ICU) delirium.
Methods
This retrospective cohort study was conducted in 2 adult medical ICUs at a single tertiary care center in Boston, Massachusetts, from October 1, 2015, to May 31, 2016. The study included 322 patients stratified into those who first received antipsychotics < 48 hours after first positive or unscorable (due to sedation) modified Confusion Assessment Method (CAM-ICU-m) (early), > 48 hours after first positive or unscorable CAM-ICU-m (late), and never received antipsychotics. Primary outcomes were hours alive without delirium or coma and likelihood of delirium-coma resolution. Secondary outcomes included ventilator-free hours, likelihood of extubation, and 10-day mortality. In post hoc exploratory analyses, outcomes were reanalyzed excluding comatose patients.
Results
Mean ± SD delirium-coma-free hours were 63 ± 87 for patients who received antipsychotics early, 66 ± 92 for those who received antipsychotics late, and 89 ± 107 for those who never received antipsychotics (P = .71). Antipsychotic exposure did not impact delirium-coma resolution. Mean ventilator-free hours were 103 ± 87 for patients who received antipsychotics early, 90 ± 83 for those who received antipsychotics late, and 89 ± 101 for patients who never received antipsychotics (P = .11). The hazard ratio (HR) for 10-day mortality among patients who received antipsychotics early was 0.68 (95% CI, 0.37-1.22) and 0.30 (95% CI, 0.10-0.88) for those who received antipsychotics late compared to those who never received antipsychotics (P = .03). After excluding comatose patients, the effect of antipsychotics on 10-day mortality was no longer observed (early HR = 0.57, 95% CI, 0.30-1.07; late HR = 0.57, 95% CI, 0.28-1.18; never HR = 1 [reference]; P = .14).
Conclusion
Antipsychotics were not associated with changes in delirium-coma-free hours or ventilator-free hours.