Dex is a sedative agent that acts via a unique alpha-2 agonist mechanism. It produces sedation while frequently preserving the ability of the patient to interact with other individuals such as caregivers or family. Other properties of Dex including respiratory stability, sympatholysis, and analgesia make it an important new drug for patients requiring sedation in the critical care setting. Although only minimally explored at this time, additional areas of potential use may include amelioration of opioid, alcohol, and sedative withdrawal syndromes, use for sedation in settings outside the critical care unit, and use in pediatric intensive care^93–96.

The primary known risks of Dex are extensions of its alpha-2 agonist mechanism: hypotension and bradycardia. Both are readily manageable with fluid administration and atropine. At higher plasma concentrations that may occur during loading of the drug, hypertension may be briefly seen. Sympatholytic effects of Dex may be particularly useful for hypertensive or tachycardic patients who require sedation. In hemodynamically marginal or unstable patients, however, the potential for significant hypotension should be considered. A careful consideration of volume status and potential conduction abnormalities is necessary before starting the drug in any patient.

Sedation in the ICU is often administered for days to weeks. Presently, the safety of Dex has only been documented for infusions up to 24 hours due to a lack of controlled studies extending beyond this time frame. As a result, the agent is approved only for <24 hour use. No adverse effects from long-term infusions, however, have been observed in small studies.^38,39 Unanswered questions include the potential for tolerance and withdrawal, accumulation of parent drug and/or metabolites, and potential changes in the pharmacokinetic profile of long term infusions of Dex. Although Dex already represents a significant addition to the arsenal of ICU sedatives, further work is necessary to identify patient groups most likely to benefit.