Pharmacologic Treatment of Intensive Care Unit Delirium and the Impact on Duration of Delirium, Length of Intensive Care Unit Stay, Length of Hospitalization, and 28-Day Mortality

Abstract

Objective: To determine whether treatment of delirium affects outcomes.

Patients and methods: A retrospective cohort study of patients admitted to the medical intensive care unit (ICU) from July 1, 2015, through June 30, 2016, was conducted. Patients with ICU delirium, defined by a positive Confusion Assessment Method for the ICU score, were included. Patients were stratified into 4 treatment groups based on exposure to melatonin and antipsychotic agents during ICU stay: no pharmacologic treatment, melatonin only, antipsychotics only, and both melatonin and antipsychotics. A time-dependent cause-specific hazards model with death as a competing risk was used to evaluate the effect of melatonin or antipsychotic drug use for delirium on duration of ICU delirium, length of ICU stay, and length of hospitalization. A logistic regression was used to evaluate 28-day mortality. Covariates significantly associated with exposure to melatonin and antipsychotics were included in the minimally adjusted model. Covariates significantly associated in the minimally adjusted model were included in a final adjusted model.

Results: A total of 449 admissions to the medical ICU were included in the analysis. Exposure to melatonin or antipsychotic agents did not reduce the duration of ICU delirium, ICU/hospital length of stay, or 28-day mortality. However, antipsychotic use only was associated with longer hospitalization.

Conclusion: Antipsychotic drugs for the treatment ICU delirium may not provide the benefit documented in earlier literature. Further investigation on patient selection, type of antipsychotic, and dosing is needed.