Effect of Tropisetron on Prevention of Emergence Delirium in Patients After Noncardiac Surgery: A Trial Protocol

IMPORTANCE: Postoperative delirium is a frequent disorder for patients undergoing surgery and is associated with poor outcomes. Delirium may occur in the immediate period after anesthesia administration and surgery. Tropisetron, which is frequently administrated for postoperative nausea and vomiting, is also a partial agonist of α7 nicotinic acetylcholine receptors associated with neuroprotective effects. Tropisetron may be the potential pharmacological treatment to decrease delirium after noncardiac surgery. OBJECTIVE: To perform a randomized clinical trial to determine the efficacy and safety of tropisetron for prevention of emergence delirium in patients undergoing noncardiac surgery. DESIGN, SETTING, AND PARTICIPANTS: This single-center, 2-arm randomized, double-blind, placebo-controlled trial will include 1508 patients undergoing noncardiac surgery. The intervention group will receive 5 mg of intravenous tropisetron before anesthesia induction, and patients in the control group will receive a placebo. The primary end point is the incidence of emergence delirium within 1 hour after tracheal tube removal, measured by the Confusion Assessment Method for the Intensive Care Unit score. The main secondary outcome is the incidence of postoperative delirium measured at 3 days of follow-up. An intention-to-treat principle will be used for all analyses. DISCUSSION: Delirium remains the most common neuropsychiatric complication for patients after surgery. This will be the first randomized clinical study to evaluate whether tropisetron is effective in preventing emergence delirium. Results from this study will provide evidence for alteration of daily practice. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04027751