Assessment of Delirium as an Independent Predictor of Outcome among Critically Ill Patients in Intensive Care Unit: A Prospective Study

Abstract

Background: Delirium is frequently observed among critically ill patients in the intensive care unit. Although a preventable and reversible process, it is associated with greater morbidity and mortality. Early recognition and interpreting the predisposing and precipitating risk factors for delirium can improve outcomes among these patients. Objective: A prospective observational study was conducted with the primary objective to evaluate the incidence of delirium in a mixed adult intensive care unit. The secondary objectives were the evaluation of risk factors and outcomes of delirium. Methods: All patients who were more than 18 years of age and with an ICU stay of more than 24 hours were included in the study. Patients with prior history of neurological disorders, psychosis, and who were deaf were excluded. Eligible patients were evaluated by the residents to detect delirium using confusion assessment method for the intensive care unit as a tool. Results: A total of 110 patients were included, and delirium was detected in 41 patients (37.3%). Among the predisposing risk factors, only hypertension was significantly associated with delirium. Among precipitating factors, mechanical ventilation, use of physical restraints and presence of window/natural light exposure, high Acute Physiology and Chronic Health Evaluation II scores, use of opioids, and benzodiazepines were associated with delirium. In multivariate risk regression analysis, presence of window/natural light exposure [odds ratio (OR), 55.52; 95% CI (8.887–346.904)]; (p <0.001) and duration of stay in ICU OR (1.145); 95% CI (1.058–1.238) (p = 0.001) were independent risk factors of delirium. Also, high mortality (53.7%) was observed among the delirious group of patients. Conclusion: Delirium is a common problem in the ICU and is associated with poor outcomes. Various risk factors are linked to ICU environment.