Purposes of review
Critically ill patients frequently require mechanical ventilation as part of their care. Administration of analgesia and sedation to ensure patient comfort and facilitate mechanical ventilation must be balanced against the known negative consequences of excessive sedation. The present review focuses on the current evidence for sedation management during mechanical ventilation, including choice of sedatives, sedation strategies, and special considerations for acute respiratory distress syndrome (ARDS).
The Society of Critical Care Medicine recently published their updated clinical practice guidelines for analgesia, agitation, sedation, delirium, immobility, and sleep in adult patients in the ICU. Deep sedation, especially early in the course of mechanical ventilation, is associated with prolonged time to liberation from mechanical ventilation, longer ICU stays, longer hospital stays, and increased mortality. Dexmedetomidine may prevent ICU delirium when administered nocturnally at low doses; however, it was not shown to improve mortality when used as the primary sedative early in the course of mechanical ventilation, though the majority of patients in the informing study failed to achieve the prescribed light level of sedation. In a follow up to the ACURASYS trial, deep sedation with neuromuscular blockade did not result in improved mortality compared to light sedation in patients with severe ARDS.
Light sedation should be targeted early in the course of mechanical ventilation utilizing daily interruptions of sedation and/or nursing protocol-based algorithms, even in severe ARDS.