Background: Delirium is one of the most common problems in ICUs. This study was conducted to investigate the prevalence of delirium, its related factors and short-term outcomes in ICU patients.

Materials and Methods: In this cross-sectional study, 270 ICU patients were selected by convenience sampling. The Richmond Agitation-Sedation and Glasgow Coma Scales were used to assess the level of consciousness in the patients. Moreover, Confusion Assessment method (CAM-ICU) was used to assess delirium at two times on morning and evening. Some delirium-related factors including health and demographic characteristics, mechanical ventilation, hospitalization length, return to the ICU and mortality rate were evaluated.

Results: Results showed that 120 patients (44.5%) experienced delirium. There was a significant correlation between the age, marital status, hypertension, seizure, employment and delirium. Moreover, other variables like sex, literacy, smoking, background diseases, history of surgery, numbers of catheters and medications, hospitalization period and mechanical ventilation were significantly associated with delirium incident. Previous surgical history, the number of catheters and medications were the predictors of delirium.

Conclusion: The prevalence of delirium is relatively high in ICU patients. Furthermore, the length of hospitalization, duration of mechanical ventilation and also mortality rate were increased in the patients with delirium.