Single or double-injection technique in axillary block: the success of motor and sensor blockade

Sa？etak Background and Purpose: Axillary brachial plexus block is the method of choice for surgical procedures of upper arm except shoulder region. Distribution of local anaesthetic toward neurovascular space may be a reason for failed block. We investigated the axillary block effectiveness by singeand double-injection technique. Materials and Methods: Ninety patients (21–81 old; ASA I-IV) scheduled for upper arm surgery were divided in three equal groups during prospective, double-blind study. Nerve position was located with neurostimulator (Stimuplex？ HNS 11)(0.5 mA, 2Hz and 0.1 ms). In Group S (single-shot), mixture of 30 mL (15 mL 0.5% bupivacaine and 15 mL 2% lidocaine) was injected only above axillary artery (25 mL around median and 5 mL around musculocutaneus nerve). In Group U and R (double-shot), the same mixture of local anaesthetic was applied above (10 mL around median and 5 mL around musculocutaneus nerve) and below axillary artery (15 mL around radial or ulnar nerve). Motor and sensor block were determined (Bromage scale, Pinprick method). Statistic analysis was done (SSP11.0). Results and Conclusions: Effective block analgesia and anaesthesia was achieved in shorter time in Group R (18+/4 and 26+/–3 min)(Group U: 34+/–4 and 41+/–3 min, Group S: 35+/–4 and 45+/–2 min) (P=0.0000) (Table 2). Block effectiveness was significantly higher after radial nerve stimulation (92%)(Group U 88% and S 76%) (P=0.630). Faster motor block was achieved in Group R (18+/–4)(Group U 26+/–3 and S 35+/–4 min) (P=0.000). Double-shot technique with primar radial nerve stimulation, allows better motor and sensor axillary block in comparison with single-shot technique