[Importance of the needle in regional anesthesia].

The safety of regional anesthesia lies on a set of factors, namely, selection of the adequate technique, skill and proper training from the part of anesthesiologists and use of right equipment. The needle, as a prolongation of the hand of the anesthesiologist, must provide references in technique either by itself or joined to an objective method of nerve localization; this will result in a high percentage of success without iatrogenesis. We have reviewed 1,132 cases of regional anesthesia and grouped them into: intradural anesthesia, epidural anesthesia, and plexus anesthesia. We have evaluated the equipment used according to the success and iatrogenesis directly produced by the needle. Results were analyzed by Fisher's exact test and were statistically significant in the three groups, a fact that would indicate some specificity of the characteristics of the needle in each group of techniques. It would seem reasonable to adopt those techniques appearing to be the most efficacious after analysis in order to increase percentage of success and achieve the greatest safety in the clinical practice of anesthesiologists.