General anesthesia vs perimedullary anesthesia

peer reviewedPerimedullary anesthetic techniques (epidural or spinal anesthesia), by themselves or combined with general anesthesia offer several advantages in the postoperative period when compared with general anesthesia alone. The incidence of postoperative respiratory and cardiovascular complications is decreased. The physiologic stress reaction, with its associated hypercoagulable state and immune depression, is attenuated. Finally, the resumption of gastrointestinal function is hastened. These benefits of central neural blockade are noted most clearly when the techniques are used for several days postoperatively, most often by catheter based epidural analgesia. The use of local anesthetic agents in the analgesic mixture would appear to be important. This is likely because these substances inhibit the sympathetic nervous system and spinal reflex axes. The role of this inhibition in the advantages of perimedullary techniques is probably important. It is important to note that inhibition of the sympathatetic nervous system can be associated with indesirable consequences in certain patients. These techniques must therefore be used cautiously, and patients who benefit from them must receive careful surveillance