Effect of two-injection technique versus four-injection of ropivacaine in brachial plexus nerve block

  Objective  To compare two-injection and four-injection techniques of ropivacaine combined with ultrasonography (USG) and nerve stimulator in patients with brachial plexus nerve block.

  Methods  Sixty patients were randomly divided into two groups, given injection of a mixture of ropivacaine and normal saline for 30 mL. After the blockage of the musculocutaneous nerve in both the groups, the two-injection group was given median nerve blockage while the four-injection group was additionally given ulnar nerve, and radial nerve blockage. Sensorial blockage in brachial plexus nerves was evaluated with pinprick test, and motor block was evaluated by contraction of the muscles innervated by each nerve. The start time of blockage, its effectiveness and duration were recorded, and adverse events and complications, visual analog scale (VAS) scores, and postoperative patient satisfaction were observed.

  Results  Sufficient analgesia and anaesthesia were achieved, So no additional local anaesthetics in both the groups was needed. A faster and more effective complete block were achieved in four-injection group. In the two-injection group, the nerve block successfully achieved excepted for radialis block in one patient. The blockage procedure lasted longer and VAS scores was higher in the four-injection group. No statistical difference was found with regard to patients′ satisfaction, and no adverse effects and complications were observed in any group.

  Conclusion  Although the multi-injection method takes more time, it provides faster anaesthesia and more complete blockage than the two-injection method.