Anestéziológia a intenzívna medicína 1/2014

Incidence and risk factors of delirium in patients after cardiac surgery

Post cardiac surgery delirium is a severe complication. This study tried to evaluate the early postoperative delirium risk factors and to identify which of them can be modified in order to optimize perioperative management. It is a prospective observational study. 250 consecutive cardiac surgery patients took part in the study. Cardiac surgery, the anesthetic regiment and the postoperative management were standardized. The incidence and the risk factors of the postoperative delirium were analyzed by univariate and multivariate analysis. Delirium was assessed with the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Delirium developed in 52 patients (20,8 %). Univariate analysis of the variables confirmed that older age (p = 0,0001), the higher EuroSCORE II value (p = 0,0001), longer cardiopulmonary bypass time (p = 0,0001) and longer aortic cross clamp time (p = 0,0001) were strongly independently associated with postoperative delirium. The benzodiazepines administration, it was shown to be an intermediate predictor for developing postoperative delirium (p = 0,055). Advanced age and higher Euroscore II value represent non-modifiable risks factors of postoperative delirium. Longer duration of cardiopulmonary bypass and longer aortic cross clamp time could be regarded as semi-modifiable risks factors. Modifiable risk factor of postoperative delirium represents dose of benzodiazepines.

Keywords: postoperative delirium, risk factors, cardiac surgery.