Comparison of ultrasound and ultrasound plus nerve stimulator guidance axillary plexus block

Abstract

Objective: To evaluate the characteristics of axillary plexus blockade applied using ultrasound only and using ultrasound together with nerve stimulator in patients undergoing planned forearm, wrist or hand surgery.

Methods: This randomised, prospective, double-blinded, single-centre study was conducted at Ankara Numune Training and Research Hospital, Ankara, Turkey, from November 2014 to August 2015, and comprised patients undergoing forearm, wrist or hand surgery. Participants were separated into 2 groups. In Group 1, the nerve roots required for the surgical site were located one by one and local anaesthetic was applied separately to each nerve for the block. In Group 2, the vascular nerve bundle was located under ultrasound guidance and a total block was achieved by administering all the local anaesthetic within the nerve sheath. In the operating room, standard monitorisation was applied. Following preparation of the skin, the axillary region nerve roots and branches and vascular structures were observed by examination with a high-frequency ultrasound probe. In both groups, a 22-gauge, 5cm block needle was entered to the axillary region with visualisation of the whole needle on ultrasound and 20ml local anaesthetic of 0.5% bupivacaine was injected. SPSS 19 was used for data analysis.

Results: Of the 60 participants, there were 30(50%) in each group. The mean age was 39.1±15 years in the group 1 which was the ultrasound nerve stimulation group, and 41.5±14.3 years in group 2. The duration of the procedure was longer in group I than in group 2 (p<0.05). Patient satisfaction values during the procedure were higher in group 2(p<0.05). In the ulnar sensory examination, the values of the patients in group 1were higher at 10, 15, 20 and 25 minutes (p<0.05). In the median, radial and ulnar motor examination, the values of the patients in group 1were higher at 15 and 20 minutes (p<0.05).

Conclusions: Brachial plexus blockade via axillary approach guided by ultrasound offered excellent quality of sensory and motor block equivalent to that of the nerve stimulator-guided technique.

Keywords: Ultrasound, Nerve stimulation, Axillary plexus block..