Delirium is seen in at least 50% of patients after cardiac surgery. Patients with delirium have a greater likelihood extended hospital stay, long-term cognitive impairment, and death after surgery. Cardiac surgery and cardiopulmonary bypass trigger an inflammatory response. This response may contribute to neuroinflammation, brain injury, and postoperative delirium.
Steroids may decrease neuroinflammation and the risk of postoperative delirium. Dr. Anne-Mette C. Sauër, Department of Anesthesiology, University Medical Center Utrecht, Utrecht, the Netherlands, and coauthors randomized 737 patients aged 18 years or older undergoing cardiac surgery with cardiopulmonary bypass at their institution to receive a single 1 mg/kg IV injection of dexamethasone (maximum 100 mg), or placebo at the time of induction of anesthesia. The results of their study are published in this month’s issue of Anesthesia & Analgesia in the article titled “Intraoperative Dexamethasone and Delirium after Cardiac Surgery: A Randomized Clinical Trial.”
Delirium incidence over the first 4 postoperative days was about 14% in both the dexamethasone and placebo groups. The daily amount of administered haloperidol, benzodiazepines, and opioids was similar between the 2 groups on each of the 4 assessment days. The proportion of patients who received ≥1 dose of haloperidol over the course of the 4-day assessment period did not differ between the two groups. Restraint use was also no different between groups.
Delirium incidence was lower than that seen in other trials, but it was similar to the results observed in another large trial. Would higher doses of dexamethasone have demonstrated a benefit vs. placebo? Would dexamethasone administered intraoperatively or postoperatively have shown benefit?
This was an adequately powered randomized trial that addresses an important question regarding the pathogenesis of delirium. It is certainly not the end of the story, however. As Dr. Charles H. Brown IV, Division of Cardiac Anesthesia, Johns Hopkins University School of Medicine, Baltimore, Maryland, and colleagues write in “Delirium, Steroids, and Cardiac Surgery,” the editorial accompanying the article, “Sauër et al. are to be commended for performing a large, rigorous randomized trial of corticosteroids on delirium after cardiac surgery. Their results provide compelling evidence that perioperative use of high dose dexamethasone does not prevent delirium after cardiac surgery. Further high-quality randomized trials are needed to identify perioperative strategies to reduce postoperative delirium.”