Thoracic epidural anaesthesia for coronary artery bypass graft surgery. Effects on postoperative complications.
We have performed a retrospective analysis of the peri-operative course of 218 consecutive patients who underwent routine coronary artery bypass graft surgery in this institution. All patients received a standardised general anaesthetic using target-controlled infusions of alfentanil and propofol. One hundred patients also received thoracic epidural anaesthesia with bupivacaine and clonidine, started before surgery and continued for 5 days after surgery. The remaining 118 patients received target-controlled infusion of alfentanil for analgesia for the first 24 h after surgery, followed by intravenous patient-controlled morphine analgesia for a further 48 h. Using computerised patient medical records, we analysed the frequency of respiratory, neurological, renal, gastrointestinal, haematological and cardiovascular complications in these two groups. New arrhythmias requiring treatment occurred in 18% of the thoracic epidural anaesthesia group of patients compared with 32% of the general anaesthesia group (p = 0.02). There was also a trend towards a reduced incidence of respiratory complications in the thoracic epidural anaesthesia group. The time to tracheal extubation was decreased in the epidural group, with the tracheas of 21% of the patients being extubated immediately after surgery compared with 2% in the general anaesthesia group (p < 0.001). There were no serious neurological problems resulting from the use of thoracic epidural analgesia.