[The effect of wound perfusion on the relief of postoperative pain]

The efficacy of wound perfusion (WP) with lidocaine for postoperative pain relief was studied in patients with median incision for cholecystectomy. Twenty four patients were divided into 3 groups according to the method of postoperative pain relief; group C, n = 8: intramuscular injections of penta-zocine 30 mg administered on demand, group WP, n = 8: WP with continuous lidocaine perfusion for 24 hours (plus pentazocine on demand); group EPI, n = 8: buprenorphine administered epidurally for 24 hours (plus pentazocine on demand). Pain scores at 0, 6, 12, 24, 48, hours after operation were examined. Arterial blood gas analysis, FVC and FEV1 were measured preoperatively and on the first postoperative day. Pain scores at 0 and 24 hours in group WP and EPI were significantly lower than those in group C. There were no significant differences in the scores between group WP and EPI at all the points. Analgesic requirement was significantly reduced in group WP and EPI compared with group C. FVC, FEV1 and PaO2 were significantly reduced postoperatively in every group but there were no differences among three groups. PaCO2 significantly increased postoperatively in group C and EPI. We conclude that the technique of wound perfusion with lidocaine is effective and safe for postoperative pain relief.