The Use of Epidural Analgesia in Cardiac Surgery Should Be Encouraged

To the Editor: We read Chaney’s (1) review of regional techniques in cardiac surgery. The risk of hematoma formation as a result of using epidural catheters in cardiac surgery is theoretical, calculated to be in the range of 1:1500 (2) to fewer than 1 in 10,000 procedures (3). At the time of this calculation about 7% of cardiac anesthesiologists used epidural anesthesia in cardiac surgery (4). Since then, epidural analgesia has become more popular in cardiac surgery with more than 10,000 cases reported in the literature. There have been no reported cases of epidural hematoma due to full systemic intraoperative heparinization. The advantages of epidural anesthesia, compared with conventional anesthesia techniques, include better pain control, fewer pulmonary and renal complications, and fewer arrhythmias (5–8). Some authors have even recommended regional anesthesia as a technique of choice in cardiac surgery (8). The case of epidural hematoma cited in Chaney’s review has been discussed before (9). The hematoma was due not to intraoperative systemic heparinization, but rather to the combination of administration of full systemic heparin, administration of IV alteplase, and removal of the catheter despite a greatly increased prothrombin time (10). Consequently, this case report should not discourage anesthesiologists from using epidural anesthesia and analgesia in cardiac surgery, provided that strict guidelines for regional techniques are followed (11). The three other cases of “disastrous epidural hematomas” anecdotally reported by Chaney (1,12) have not been published. As a result, the circumstances under which they occurred cannot be judged. Recent meta-analyses have strongly supported using epidural anesthesia in cardiac surgery (6–8), as long as strict guidelines are followed (13). In one of these authors’ hospital settings (Hemmerling), more than 500 epidural catheters have been placed for different cardiac surgical procedures with zero incidence of epidural hematoma. The key to avoiding epidural hematoma is an environment in which all members of the health care team are aware of the inherent risk of hematoma formation, maintain good communication, and judiciously follow the guidelines for insertion and removal of epidural catheters. In conclusion, we believe three key factors are important: The establishment of an international registry for epidural hematomas in cardiac surgery, A large multicenter, controlled, clinical trial to investigate whether epidural analgesia can indeed reduce morbidity and mortality after cardiac surgery, and Awareness that the practice of epidural analgesia in cardiac surgery requires a vigilant environment in which possible complications are readily recognized and appropriately managed. Thomas M. Hemmerling, MD, DEAA Department of Anesthesiology Montreal General Hospital McGill University Montreal, Canada thomashemmerlin[email protected] George Djaiani, MD Department of Anesthesiology University of Toronto Toronto, Ontario, Canada Patricia Babb University of Chicago Chicago, IL John P. Williams, MD Department of Anesthesiology University of Pittsburgh Pittsburgh, PA