Prediction of cerebral outcome after extracorporeal circulation

Abstract

50 open-heart patients were investigated using simultaneous clinical, electroencephalographical (EEG) and neuropsychological evaluation in order to assess the possibilities of predicting the postoperative outcome with preoperative measures. The presence of one or more of the following indices was prognostically unfavourable: a history of cerebrovascular diseases or syncope; delta or sharp wave EEG abnormalities or low quantitative EEG mean frequency; a poor performance score in one of the psychometric tests (colour naming). Using these measures, 28 cases with presumably high risks were indicated, and 24 (86%) sustained cerebral complications attributable to the operation. The observations contrast clearly with previous studies whose predictions, using only one single criterion, have proved invalid. A significant level of prediction seems to be obtainable, but only by the simultaneous consideration of several different cerebral functions. The prognostic approach may offer one way of achieving the necessarily needed improved cerebral safety in cardiac surgery.