Effect Of Exogenous Melatonin on the Incidence of Delirium and Its Association with Severity of Illness in Postoperative Surgical ICU Patients

Abstract

Background: Delirium is common in critically ill intensive care unit (ICU) patients and has been documented in up to 87 percent of patients. Sleep deprivation and delirium have been associated. Alteration of melatonin production has been associated with delirium. Melatonin acts via melatonin receptors present in the suprachiasmatic nuclei (SCN) and promotes sleep by attenuating the wake-promoting signal from the SCN. Objective: To determine the relationship between exogenous melatonin and the incidence of delirium and its association of with severity of illness, measured in term of APACHE II, procalcitonin level at the time of admission and daily SOFA score. Patients and Methods: Design: Randomised placebo-control study. Setting: the study was conducted in critical care setting in a tertiary level ICU. Participants: Postoperative patients age between 20-60 years who are going to be ventilated more than 48 hours without any contraindication to enteral medications. Interventions: Study group received melatonin 5 mg through the enteral route. Main outcome measures: To determine the effect of exogenous melatonin on the incidence of delirium in postoperative patients who require mechanical ventilation for more than 24 hours. The secondary outcome measures are procalcitonin (PCT) value at admission and disease severity scores like APACHE II and SOFA. Results: No statistically significant difference was found in admission incidence of delirium or procalcitonin. Age was higher in those patients that developed delirium (p < 0.05). Conclusions: Although the incidence of delirium is not affected by exogenous melatonin or higher APACHE scores, it had a significant correlation with higher procalcitonin, that in turn indicated an association with delirium and sepsis. It was found that there is increased risk of developing delirium with increasing age.