Sedation and neuromuscular paralysis in the ICU

Critically ill patients receiving mechanical ventilation in the ICU usually require sedative therapy and, less frequently, neuromuscular blocking agents. A combination of a sedative agent and an opioid are typically administered by continuous intravenous infusion to relieve discomfort and distress. How sedatives and neuromuscular blocking agents are used can have a significant influence on patient outcome. This article outlines the pharmacology of the commonly used drugs that are of particular relevance to the critically ill. The changes in pharmacokinetics and pharmacodynamics associated with critical illness may lead to marked accumulation and prolongation of the drug effect. Excess sedation is detrimental to patient outcome by prolonging the duration of ventilatory support and intensive care stay. The use of sedation scores and regular sedation breaks has been associated with improved outcomes by reducing excess sedation. Delerium is a common complication of critical illness and is associated with an increased morality and long-term neurocognitive problems. Recognition of delirium and appropriate management may improve outcome.