Tramadol as an adjuvant to lidocaine for axillary brachial plexus block.

Abstract

In this prospective randomized study, we evaluated the effect of tramadol as an adjuvant to axillary block. We studied 102 patients scheduled for hand surgery under axillary block with lidocaine 1.5% (epinephrine 1/200,000) and the addition of either 4 mL saline (control group), 100 mg tramadol and 2 mL saline (TL group), or 200 mg tramadol (TH group). Onset time was longer in the TH group, 16 +/- 7 min (9 +/- 3 min in control group; P = 0.01). Sensory block and time for first rescue analgesia were significantly prolonged in the TH group compared with both TL and control groups (265 +/- 119 min vs 190 +/- 87 min vs 126 +/- 48 min; P = 0.018); (734 +/- 434 min vs 573 +/- 516 min vs 375 +/- 316 min; P = 0.02). The benefit of block prolongation associated with the addition of 200 mg tramadol to lidocaine during axillary block is limited by the slow onset of the block.