pRophylactic halopEriDol Use for Delirium in iCu patiEnts With a High Risk for Delirium

The aim of this study is to determine the effects of a low dosage of prophylactic haloperidol in patients with a high risk to develop delirium, defined by an expected ICU length of stay of \>1 day. The investigators hypothesized that haloperidol prophylaxis in patients with a high risk for delirium reduces 28-day mortality, delirium and delirium related outcome. Two different dosages of haloperidol are used in this study to compare with placebo. A dosage of 1mg, or 2mg or placebo three times a day in a double-blinded fashion resulting in a three-armed multicentre randomized double-blinded placebo-controlled trial. To relate the potential beneficial effects of haloperidol to the a priori risk to develop delirium, the PREDELIRIC-model (delirium prediction model for ICU patients) will be used. This will enable the investigators to determine the preventive efficacy of haloperidol in patient groups based on their risk to develop delirium.