Does Dexmedetomidine Ameliorate Postoperative Cognitive Dysfunction? A Brief Review of the Recent Literature
Purpose of Review
Postoperative cognitive dysfunction (POCD) occurs in 20–50% of postsurgical patients with a higher prevalence in elderly patients and patients with vascular disease and heart failure. In addition, POCD has been associated with many negative outcomes, such as increased hospital length of stay, increased rates of institutionalization, and higher patient mortality. This brief review discusses select evidence suggesting an association between neuroinflammation and POCD and whether the use of dexmedetomidine, a short-acting alpha 2 agonist, may ameliorate the incidence of POCD. We review the recent evidence for neuroinflammation in POCD, dexmedetomidine’s properties in reducing inflammatory-mediated brain injury, and clinical studies of dexmedetomidine and POCD.
There is evidence to support the anti-inflammatory and immunomodulatory effects of dexmedetomidine in animal models. Several clinical investigations have demonstrated favorable outcomes using dexmedetomidine over placebo for the reduction of postoperative delirium. Few studies have used high-quality endpoints for the assessment of POCD and no demonstrable evidence supports the use of dexmedetomidine for the prevention of POCD.
While evidence exists for the neural anti-inflammatory properties of dexmedetomidine, human trials have yielded incomplete results concerning its use for the management of POCD. Dexmedetomidine may reduce acute postoperative delirium, but further studies are needed prior to recommending the use of dexmedetomidine for the direct reduction of POCD.
KeywordsDexmedetomidine Postoperative cognitive dysfunction Delirium Neuroinflammation
Compliance with Ethical Standards
Conflict of Interest
Zyad J. Carr, Theodore J. Cios, Kenneth F. Potter, and John T. Swick declare no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance
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