Regional versus general anesthesia

In summary, this article has focused upon recent randomized clinical trials to evaluate the relative protective effect of major neuraxial blockade either alone or in conjunction with general anesthesia for patients at risk for major cardiovascular perioperative morbidity. Some mechanisms that have been shown to be associated with regional anesthesia, which should be protective to the heart, have also been briefly discussed. Although the earlier, smaller trials showed a reduction in cardiac morbidity associated with regional anesthesia, this was not confirmed by larger, more recent trials. When the findings of all the trials are summed, there does not seem to be a substantial benefit associated with regional anesthesia. Some of the hemodynamic effects of regional anesthesia, and how, these might compromise some patients with cardiac disease, especially those with valvular lesions or left ventricular hypertrophy, have been addressed. These effects must be taken into account when designing any patient's anesthetic. This article has not dealt with regional anesthesia for more minor procedures, such as interscalene or axillary blockade for creation of arteriovenous fistulas for renal dialysis. The surgical trespasses that can be performed under these less physiologically stressful regional anesthetics are smaller than those that require major neuraxis blockade (e.g., aortic aneurysm resection, abdominal surgery). Therefore, these types of surgery are associated with low rates of major cardiovascular morbidity, no matter what type of anesthesia is used. This does not mean that choice of anesthetic is unimportant for these types of surgery. It is very important, and might have a major impact upon the perioperative morbidity of any given patient who has cardiovascular disease. It means, rather, that it is difficult to perform prospective, randomized clinical trials of a size large enough to determine whether there is a difference in perioperative morbidity related to choice of anesthetic.