[Along the anesthetic line: a new approach to the brachial plexus -- the subcoracoidal retrograde access]

Introduced is a new approach to the brachial plexus marked out in opposition to the common methods by some theoretical advantages. The needle is proceeded in an acute angle to the course of the plexus. Thus reduces the possibility of nerve damage. Second the insertion of catheter is simplified. The accidental puncture of the pleura is unlikely except in cases of gross deviations of the puncture instruction. In addition the plexus is hit before the musculocutaneous nerve leaves the brachial plexus. The objective of this investigation was to evaluate the usefulness of the subcoracoidal retrograde access in daily practice. Beside the influence of stimulating different fascicles or the necessity of reaching a defined low stimulation level on the success rate and effectiveness of the plexus blockade was investigated.

75 patients undergoing elective surgery in upper limb received plexus anesthesia with the subcoracoidal retrograde access. Necessary deviation of the planned direction of puncture, stimulated fascicle, the reached minimum level of stimulation, the onset of anesthesia, point of time of the complete anesthesia were recorded. Deficiencies were also recorded and registered as sufficient or insufficient nerve blockade. The success rate of the stimulation of the different fascicles were evaluated by the chi(2)-Test to find out a preference a certain fascicle. The deviation and medium of the lowest found current levels for the different fascicles were evaluated by the Kolmogorov-Smirnow Test and the Two Sample Test Z to show to what extent a certain lowest current level influences the success rate.

The overall success rate was 92 %, particularly the anesthesia in the region of the lateral cutaneous nerve of the forearm was achieved in all cases. As a side effect caused by the retrograde injection of the local anesthetic anesthesia of the shoulder was also achieved with a high frequency. The low complication rate of 3 % consists only in accidental puncture of vessels. We found no significant influence of stimulating a certain fascicle or reaching a defined minimum stimulation level on the success rate of nerve blockade.

The described subcoracoidal retrograde access to the brachial plexus (SCREP) proved to be a safe and easy method with a low complication and high success rate compared with the known practised accesses. In contrary to other authors our findings do not support the connection either between success rate and stimulating certain fascicles nor achieving a defined lowest stimulation level.