Performance of Melatonin as Prophylaxis in Geriatric Patients with Multifactorial Risk for Postoperative Delirium Development: A Randomized Comparative Study

OBJECTIVE: Postoperative delirium is the worst patient outcome. Elderly patients undergoing orthopaedic procedures under general anaesthesia are highly liable to experience delirium. Several studies supported melatonin use for the prevention of delirium. This work evaluated the prophylactic efficiency of melatonin for postoperative delirium in patients with multifactorial risk for developing delirium as elderly undergoing orthopaedic trauma surgery under general anaesthesia. METHODS: This double-blinded prospective randomized comparative study was conducted on 80 elderly patients subjected to orthopaedic interventions under general anaesthesia. Patients were randomized into group M (Melatonin group) and group NM (Non-melatonin group). Group M received 5 mg melatonin while group NM received placebo. The study drugs were given preoperatively and for the first 3 postoperative days. For the incidence of delirium, patients were evaluated using the Abbreviated Mental Test. The Pain Assessment in Advanced Dementia, sedation scores, and changes in hemodynamics were recorded. RESULTS: The incidence of delirium was significantly lower postoperatively in M group (25%) relative to NM group (52.5%) (P < .001, OR = 2.3. 95% CI = −0.44, + 1.23). Abbreviated Mental Test scores at postanaesthesia care unit and day 0 showed a highly significant differences. However, Abbreviated Mental Test scores had no significant difference within the 3 postoperative days. Heart rate was significantly lower in M group after 50 minutes from the start of surgery. Mean blood pressure, Pain Assessment in Advanced Dementia, and sedation scores showed insignificant differences. CONCLUSION: Perioperative melatonin treatment could reduce the incidence of postoperative delirium in the studied population, and it could be considered a prophylactic medication.