Abstract P17: Delirium in the Cardiovascular Intensive Care Unit: Implementation of a Screening Tool, Prevalence and Lessons Learned

Abstract

Background: Delirium is common among critically ill patients (pts) and can lead to significant morbidity and mortality; yet the impact of delirium in a medical/surgical cardiovascular intensive care unit (CVICU) is unknown. Objectives: We sought to (1) determine the prevalence and risk factors for delirium in a CVICU using the Confusion Assessment method for the ICU (CAM-ICU); and (2) measure the effect of educating and implementing CAM-ICU in routine assessment on attitudes and knowledge gaps regarding delirium among CVICU staff. Methods: CVICU nurses were educated on delirium and trained in bedside CAM-ICU assessment. The CAM-ICU was performed at least once per shift, and reported during rounds. A survey assessed CVICU nurse attitudes and knowledge of delirium pre-and post-CAM-ICU implementation. Detailed clinical data were then prospectively obtained on 200 consecutive CVICU pts. Dementia or expected lengths of stay (LOS) < 1 day were exclusions. Results: Median CVICU LOS was 3 days (IQR 2, 5), the median APACHE II score was 23 (IQR 11, 28), and CVICU mortality was 4%. The prevalence of delirium was 26%; similar among medical (n=96) and surgical (n=104) pts. Compared with pre-implementation, post-implementation surveys demonstrated improvements in CAM-ICU use (53% vs 98%), knowledge of delirium and outcomes, and importance of CAM-ICU data for patient care. Using a negative binomial model, the prior use of statins (p = 0.01), dexmedetomidine (p = 0.05), and benzodiazepines (p = 0.05) were associated with the development of delirium, with a trend toward increasing age (p = 0.17). No association with cardiac output, on-pump surgery, or APACHE II score was observed. In addition, restraint use (chi-square 5.2; p = 0.02) or statins (chi-square 4.4; p = 0.04) during the previous 24 hours were associated with the daily prevalence of delirium. Conclusions: A detailed education intervention implementing routine CAM-ICU assessment increased knowledge of delirium and its clinical importance. Delirium is common in the CVICU, and is associated with the restraint use, dexmedetomidine, and benzodiazepines, likely representing a need for sedation. The association of delirium with prior statin use may reflect a higher burden of cardiovascular disease in these pts.