Brachial plexus block through modified coracoid approach

Objective To evaluate the outcomes of brachial plexus block(BPB) through modified coracoid approach.Methods Sixty patients scheduled for arm surgery under BPB were randomly allocated into two groups with 30 cases each.BPB was performed through coracoid approach in group A or through axillary approach in group B directed by nerve stimulator.The nerve stimulator was programmed with the variables of current 1.0 mA and frequency 2 Hz.We inserted the needle at the edge of the axillary artery in group B or at the point 2 cm caudal and 2 cm medial to the coracoid in group A.The local anesthetics was injected when the motor response was found at one of the distal nerves(radial,ulnar or median nerve) with a current intensity of 0.3 mA.Results The needle depth of group A was significantly deeper than that of group B(P0.05).The sensory block success rate in group A was significantly higher than that in group B(P0.05).The complete sensory block time of three nerves(radial,musculocutaneous,and axillary nerve) in group A was significantly shorter than that in group B(P0.01).The motor block success rate and the biggest motor block time in group A were significantly higher than those in group B(P0.01).The biggest motor block time in group A was significantly shorter than that in group B(P0.01).Conclusion The coracoid approach provides a higher BPB success rate and a greater extent of blockade than conventional axillary approach.