The modifying effect of anesthetic technique on the metabolic and endocrine responses to anesthesia and surgery.

In spite of the fact that our knowledge on the release mechanisms of the surgical stress response is rather incomplete, several techniques are available to modulate the response. However, at present it appears that no technique is capable to effectively suppress all aspects of the injury response and the widespread use of the term "stress free anesthesia" in surgery is therefore not valid. However, continuous administration of local anesthetic agents in the epidural space is the most effective technique in so far as reduction of the stress response is concerned. The clinical implication of a variable reduction in the stress response to surgery by different anesthetic techniques remains largely unsettled, since only few controlled studies have been published on the clinical effects of pain relief and general anesthesia. However, a vast amount of data exist from controlled studies comparing regional anesthesia with local anesthetics and general anesthesia. The cumulative experience from these studies have demonstrated an advantageous effect on postoperative morbidity parameters such as blood loss, postoperative thromboembolic complications, pulmonary infective complications, gastrointestinal motility, postoperative hospital stay, etc. The most pronounced effect on morbidity in these studies is in procedures where regional anesthesia has also been demonstrated to be most effective on the surgical stress response. However, whether this is a causal relationship or a coincidental event, has not been finally answered.(ABSTRACT TRUNCATED AT 250 WORDS)