Evaluation of the Prevalence and Risk Factors of Delirium in Cardiac Surgery ICU

Introduction: Delirium is defined as an acute cognitive disorder presenting with fluctuation in cognition, apathy and non-organized thinking. It may increase morbidity, mortality, ICU stay and cost. In patients who underwent heart surgery delirium may increase post-operative complications such as respiratory insufficiency, sternum instability and need to re-operation of the sternum. The aim of this study was to evaluate the prevalence and risk factors of delirium in patients admitted to cardiac surgery.Materials and Methods: 18 years or older patients who had undergone cardiac surgeries and stayed for more than 24 hours in ICU following surgery were recruited. All subjects were assessed for signs symptoms of delirium using CAM-ICU and its risk factors. All data were analyzed by SPSS 16 at the end of the study.Results: The prevalence of delirium in these patients was 23.5% (47 patients). The mean age of patients with delirium was more than other patients (P=0.001). The Incidence of delirium in the patients with cardiopulmonary bypass surgery (CPB) was higher than the patients without CPB (P=0.01). The Incidence of delirium in the patients with Atrial fibrillation was higher than patients without it (P=0.002). The Incidence of delirium in the patients with CVA history was higher than the patients without CVA history (P=0.032). The mean time of mechanical ventilation in the delirious patients was more than other patients (P=0.01).Conclusion: Older Age, CPB, history of CVA, Atrial Fibrillation, and prolonged mechanical ventilation are considered as the risk factors of delirium in cardiac surgery patients.