Multi-modal-analgesia for pain management after Hallux Valgus surgery: a prospective randomised study on the effect of ankle block

BACKGROUND: Pain and emesis are the two major complaints after day case surgery. Local anaesthesia has become an important part of optimizing intra and post-operative pain treatment, but is sometimes not entirely sufficient. The aim of the present study was to study the effect of adding an ankle block to a multi-modal analgesic approach on the first 24-hour-need for rescue analgesia in patients undergoing elective Hallux Valgus surgery. TYPE OF STUDY: Prospective, randomized patient-blind study comparing ankle block with levo-bupivacaine, lidocaine and Saline placebo control. METHODS: Ninety patients were studied comparing ankle block (15 cc) using levo-bupivacaine 2.5 mg/ml, lidocaine 10 mg/ml or placebo (saline) on day-case elective Hallux Valgus surgery, supported by general anaesthesia in all cases. Primary study endpoint was number of patient's requiring oral analgesics during the first 24 post-operative hours. RESULTS: Ankle block had no effect on need for rescue analgesia and pain ratings during the 1(st )24 postoperative hours, there was no difference seen between placebo and any of the two active local anaesthesia studied. The only differences seen was that both lidocaine and levo-bupivacaine reduced the intra-operative need for anaesthetic (sevoflurane) and that levo-bupivacaine patients had a lower need as compared to the lidocaine patients for oral analgesics during the afternoon of surgery. CONCLUSION: Adding a single shot ankle block to a multi-modal pain management strategy reduces the need for intra-operative anaesthesia but has no major impact of need of rescue analgesics or pain during the first 24-hour after surgery.