Dexmedetomidine may not reduce risk of AF or delirium after cardiac surgery: Lancet
USA: There is no need for dexmedetomidine infusion for the reduction of delirium or atrial fibrillation in patients undergoing cardiac surgery, suggests a recent study. According to the study, published in The Lancet journal, dexmedetomidine infusion initiated at anesthetic induction and continued for 24 hours did not help in the reduction of postoperative delirium or atrial arrhythmias in patients recovering from cardiac surgery.
Delirium and atrial fibrillation are common complications of cardiac surgery. Dexmedetomidine has properties of sedative agents and might help in reducing the risk of complications. This study by Prof Alparslan Turan, Cleveland Clinic, Cleveland, OH, USA, and colleagues aimed to establish whether dexmedetomidine reduces the incidence of delirium and incidence of new-onset atrial fibrillation.
The researchers performed a randomized, placebo-controlled trial at six academic hospitals in the USA. It enrolled patients who had cardiac surgery with cardiopulmonary bypass. They were randomly assigned in the ratio 1:1 to receive dexmedetomidine or normal saline placebo, the randomization was computer-generated. Patients, caregivers, and evaluators were all masked to treatment.
Participants were given either dexmedetomidine infusion or saline placebo started before the surgical incision at a rate of 0·1 μg/kg per h then increased to 0·2 μg/kg per h at the end of the bypass, and postoperatively increased to 0·4 μg/kg per h, which was maintained until 24 h.
The coprimary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. 798 patients of 3357 screened were enrolled from April 17, 2013, to Dec 6, 2018. The trial was stopped per protocol after the last designated interim analysis.
Key findings of the study include:
- The incidence of atrial fibrillation was 121 (30%) in 397 patients given dexmedetomidine and 134 (34%) in 395 patients given placebo, a difference that was not significant: relative risk 0·90.
- The incidence of delirium was non-significantly increased from 12% in patients given placebo to 17% in those given dexmedetomidine: 1·48.
- Safety outcomes were clinically important bradycardia (requiring treatment) and hypotension, myocardial infarction, stroke, surgical site infection, pulmonary embolism, deep venous thrombosis, and death.
- 21 (5%) of 394 patients given dexmedetomidine and 8 (2%) of 396 patients given a placebo, had a serious adverse event as determined by clinicians. 1 (<1%) of 391 patients given dexmedetomidine and 1 (<1%) of 387 patients given placebo died.
"Dexmedetomidine infusion, initiated at anesthetic induction and continued for 24 h, did not decrease postoperative atrial arrhythmias or delirium in patients recovering from cardiac surgery. Dexmedetomidine should not be infused to reduce atrial fibrillation or delirium in patients having cardiac surgery," concluded the authors.
The study, "Dexmedetomidine for reduction of atrial fibrillation and delirium after cardiac surgery (DECADE): a randomised placebo-controlled trial," is published in the journal The Lancet.