Effect of Exogenous Melatonin Administration in Critically Ill Patients on Delirium and Sleep: A Randomized Controlled Trial.

Research question: Does a "good quality" sleep, reduce the incidence of ICU related delirium? Background: Despite all the studies conducted to date, exogenous administration of melatonin in critically ill patients has shown to significantly increase plasma levels of melatonin. This study aims to demonstrate a correlation between plasma levels of melatonin, an improvement on the sleep architecture or a reduction in ICU related delirium. Participant characteristics: A sample of critically ill patients in the recovery phase of their disease were consecutively recruited to a double-blind placebo-controlled trial of 6 mg enteral melatonin versus placebo via a nasogastric feeding tube. Inclusion criteria included: patients expected to have a minimal length of 5 days of respiratory weaning, vasopressor free and with preserved absorption (defined as aspirates lesser than 400 ml 4th hourly), absence of ileus and discontinuation of sedation. Key results: Baseline delirium and agitation scores showed no statistical difference between groups when compared to post-intervention scores. Sleep studies were comparable between both groups. The arousal index (number of arousals per hour of sleep) post-intervention was not statistically different when compared to placebo or baseline. Limitations: Slow recruitment leading to an earlier termination