Postcardiotomy delirium in patients after coronary artery bypass graft surgery

Aim: Coronary artery bypass graft (CABG) surgery is giving better results, with reduced patient mortality, frequency of post-surgery myocardial infarction and other significant complications. Certain postcardiotomy delirium (PCD) disorders still cause problems as they extend the duration of hospitalization, and increase the cost of medical treatment. In this analysis we tried to identify the factors which may have an influence on the occurrence of PCD. Material and Methods: Medical records of 931 consecutive patients who underwent CABG surgery during one year were analysed. 30 medical records which included descriptions corresponding to the criteria of delirium according to ICD-10 were chosen. Pre- and intra-surgery variables which may have a potential predictive significance were analysed. Results: Transient PCD was recorded in 3.22% of patients. In univariate analysis 6 variables were evaluated as being connected with occurrence: age, NYHA III-IV, EuroSCORE, LVEF, extracorporeal circulation (ECC) time and its duration, and aorta cross-clamping time. In the logistic regression analysis the two most important independent factors having an influence on occurrence of delirium were identified as the age of the patient and the aorta cross-clamping time. Conclusions: The age of the patients and the aorta cross-clamping time seem to be the most important independent factors which may cause PCD. However, verification of this observation requires prospective research. This research shows the advisability of limiting the time of ECC and aorta cross-clamping. Such action is especially important for the group of elderly patients and it is a factor which allows the frequency of PCD incidence to be diminished. It seems that achieving the above aim may be possible not by suggesting a chosen operation technique to patients but by treatment of this group of patients by more experienced cardiac surgeons and anaesthetists.