Intravenous regional anesthesia for outpatient foot and ankle surgery: a prospective study.

A prospective study was undertaken in 39 patients undergoing 48 foot and ankle procedures using intravenous regional anesthesia (IVRA). IVRA was administered using 35 cc of 0.33% or 0.5% lidocaine. Single tourniquets inflated to 250 mm Hg were used at the ankle level. No supplemental analgesia or sedation was used. Those requiring supplemental local anesthetic infiltration were defined as IVRA failures. Thirty-one of the 39 patients (79.5%) tolerated the procedures with little or no discomfort, and 8 (20.5%) required additional local infiltration with 1% lidocaine. All 39 patients completed the procedures at the outpatient surgical unit without requiring conversion to other forms of anesthesia. Patchy non-anesthetic areas were noted in 14 patients (36.8%). In 7 patients, because the non-anesthetic areas were excluded from the operative fields, the procedures were completed without discomfort. However, in 8 patients where the non-anesthetic areas were directly involved in the operative fields, supplemental local anesthesia was required. Only 1 of the 39 patients complained of tourniquet pain. IVRA compared favorably with other methods of regional anesthesia in the lower extremity with respect to ease of technique, speed of onset, safety, and patient acceptance. However, it appears that it is less reliable than IVRA in the upper extremity. The reasons for this difference will require further investigation.