Axillary brachial plexus block--an underused technique in the accident and emergency department

OBJECTIVE: To compare axillary brachial plexus block and Bier's block as methods of providing upper limb anaesthesia. METHODS: Axillary brachial plexus or Bier's blocks were performed on all patients requiring upper limb anaesthesia in a three month period. For Bier's block, a single cuff tourniquet and 3 mg/kg 0.5% prilocaine were used. For axillary plexus block, 40 ml 1% lignocaine with adrenaline (1:200,000) were used, given by perivascular or transarterial technique. Prospective analysis was made of time to complete limb anaesthesia, type of procedure performed, and duration of limb anaesthesia. Patient perception of analgesia and satisfaction with the method of anaesthesia was assessed using a 10 point visual analogue scale. RESULTS: 75 patients underwent procedures requiring upper limb anaesthesia; 39 received axillary plexus block and 36 Bier's block. 72% of Bier's blocks and 77% of axillary plexus provided complete anaesthesia without the need for supplemental analgesia. The median time to onset of anaesthesia was 10 min for Bier's block and 32.5 min for axillary block (P < 0.001). The median duration of anaesthesia was 15 min for Bier's block and 240 min for axillary block (P < 0.001). Mean scores for analgesia were 9.7 for axillary blocks and 8.8 for Bier's block (P < 0.001). 87% of the axillary block group were completely satisfied with the method of anaesthesia, compared with 56% of the Bier's block group. CONCLUSIONS: Brachial plexus blocks are an alternative form of providing upper limb anaesthesia in the accident and emergency department. They are relatively simple to perform, well tolerated by patients, and have the advantage of providing prolonged analgesia without the need for additional medication.