INTRAOPERATIVE AWARENESS IN FAST-TRACK CARDIAC ANESTHESIA

Background: Fast-track cardiac anesthesia, using low-dose narcotics co mbined with short-acting anesthetic and sedative agents, facilitates e arly tracheal extubation after cardiac surgery. The incidence of aware ness with this anesthetic technique has not been investigated previous ly. The purpose of this study was to prospectively investigate the inc idence of intraoperative awareness with explicit memory of events duri ng fast-track cardiac anesthesia. Methods: Data were collected prospec tively over a 4-month period from 617 consecutive adult patients under going cardiac surgery at a university hospital. All patients received a fast-track cardiac anesthetic regimen, Patients underwent a structur ed interview by a research nurse 18 h after extubation. A standard set of questions was asked during this interview to determine if the pati ent had explicit memory of any event from induction of anesthesia to r ecovery of consciousness. Results: Nine patients did not complete a po stoperative interview because of death (n = 7) or postoperative confus ion (n = 2). The last memory before surgery reported in 420 (69.1%) pa tients was waiting in the holding area at the operating suite, and in the remaining 188 (30.9%) patients it was lying on the operating table before induction of anesthesia. Two patients (0.3%) had explicit memo ry of intraoperative events. One of the two patients also had explicit memory of pain. Neither patient reported adverse psychological sequel ae. Conclusions: The authors report an incidence of awareness in fast- track cardiac anesthesia of 0.3%. This is the lowest incidence of awar eness currently reported during cardiac surgery. This low incidence of awareness may be related to the use of a balanced anesthetic techniqu e involving the continuous administration of volatile (isoflurane) or intravenous (propofol) anesthetic agents before, during, and after car diopulmonary bypass.