Drug-Induced Coma and Delirium

Adverse drug events are common in the ICU and frequently have a negative impact on patient outcome and healthcare costs. A number of factors specific to the ICU setting account for this high incidence, including the complexity of the disease states present and the urgency with which they must be treated, the large number of medications administered, the presence of end-organ dysfunction, the frequent need for high-risk medications with narrow therapeutic indices, and the frequent use of intravenous infusions. Although a medicationinduced coma was previously considered the most “humane” state to optimize comfort in the critically ill, it has now been associated with increased mortality, a prolonged duration of ventilation and ICU stay, increased delirium, and greater long-term neuropsychological dysfunction including posttraumatic stress disorder. Delirium occurs frequently in the ICU and is associated with higher mortality, a longer duration of mechanical ventilation, increased ICU and hospital lengths of stay, and a number of adverse post-ICU sequelae. Acute brain dysfunction (ie, the development of new-onset coma and/or delirium) is a frequent and serious adverse event during critical illness, and its development is frequently related to medications that the critically ill patient is administered. This chapter reviews the medications that are routinely used in the ICU that have been associated with coma and delirium, highlights those factors shown to increase the risks for these medications to cause acute brain dysfunction, and provides strategies to minimize the incidence of medication-associated coma and delirium in the critical care setting.