Impact of dexmedetomidine on the incidence of delirium in elderly patients after cardiac surgery: A randomized controlled trial.
BACKGROUND
Delirium is a frequent complication after cardiac surgery and its occurrence is associated with poor outcomes. The purpose of this study was to investigate the impact of perioperative dexmedetomidine administration on the incidence of delirium in elderly patients after cardiac surgery.


METHODS
This randomized, double-blinded, and placebo-controlled trial was conducted in two tertiary hospitals in Beijing between December 1, 2014 and July 19, 2015. Eligible patients were randomized into two groups. Dexmedetomidine (DEX) was administered during anesthesia and early postoperative period for patients in the DEX group, whereas normal saline was administered in the same rate for the same duration for patients in the control (CTRL) group. The primary endpoint was the incidence of delirium during the first five days after surgery. Secondary endpoints included the cognitive function assessed on postoperative days 6 and 30, the overall incidence of non-delirium complications within 30 days after surgery, and the all-cause 30-day mortality.


RESULTS
Two hundred eighty-five patients were enrolled and randomized. Dexmedetomidine did not decrease the incidence of delirium (4.9% [7/142] in the DEX group vs 7.7% [11/143] in the CTRL group; OR 0.62, 95% CI 0.23 to 1.65, p = 0.341). Secondary endpoints were similar between the two groups; however, the incidence of pulmonary complications was slightly decreased (OR 0.51, 95% CI 0.26 to 1.00, p = 0.050) and the percentage of early extubation was significantly increased (OR 3.32, 95% CI 1.36 to 8.08, p = 0.008) in the DEX group. Dexmedetomidine decreased the required treatment for intraoperative tachycardia (21.1% [30/142] in the DEX group vs 33.6% [48/143] in the CTRL group, p = 0.019), but increased the required treatment for postoperative hypotension (84.5% [120/142] in the DEX group vs 69.9% [100/143] in the CTRL group, p = 0.003).


CONCLUSIONS
Dexmedetomidine administered during anesthesia and early postoperative period did not decrease the incidence of postoperative delirium in elderly patients undergoing elective cardiac surgery. However, considering the low delirium incidence, the trial might have been underpowered.


BACKGROUND
ClinicalTrials.gov NCT02267538.
Department of Anesthesiology and Critical Care Medicine, Peking University First Hospital, Beijing, China.
Xue
X
Li
Department of Anesthesiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Jing
J
Yang
Center for Clinical Epidemiology & Evidence-Based Medicine, Beijing Children's Hospital, Capital Medical University, Beijing, China.
Xiao-Lu
XL
Nie
Department of Anesthesiology and Critical Care Medicine, Peking University First Hospital, Beijing, China.
Yan
Y
Zhang
Department of Biostatistics, Peking University First Hospital, Beijing, China.
Xue-Ying
XY
Li
Department of Anesthesiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Li-Huan
LH
Li
Department of Anesthesiology and Critical Care Medicine, Peking University First Hospital, Beijing, China.
Dong-Xin
http://orcid.org/0000-0002-3205-1836
DX
Wang
Section of Anaesthetics, Pain Management and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
Daqing
D
Ma
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures; D020927:Dexmedetomidine / Q000008:administration & dosage* / Q000009:adverse effects*; D004311:Double-Blind Method; D000071257:Emergence Delirium / Q000139:chemically induced / Q000401:mortality; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D011184:Postoperative Period; D013997:Time Factors
D020927:Dexmedetomidine