Comparison of the Effect of Subcutaneous Injection of Bupivacaine 0.5% before and after Appendectomy on the Pain after Surgery

Introduction & The aim of this study is comparison of the effect of subcutaneous injection of bupivacaine 0. 5% before and after appendectomy on the pain after surgery. A clinical trial randomized single-blind study was conducted on 150 male patients with preoperative tentative diagnosis of acute appendicitis. They were randomly divided into there groups. In group one (50 patients) bupivacaine of 0. 5% was injected into the skin through a subcutaneous tissue incision. In group 2 (50 patients) injection was performed postoperately. Group 3 (50 patients) received no injection. The pain score of patients was evaluated by the visual analogue scale (VAS) at 6، 12، 24 and 48h after surgery. Time to first analgesia request، total analgesic (pethidine) requirement in the first 48h after operation were recorded. VAS6 score in the injected groups was lower than non-injected group (P<0. 005). Post incisional VAS6 score was lower than preincisional score (P<0. 041). There was no significant differences between other scores in groups. First request to analgesia was 5. 7±3. 9 h in group 1،5. 8±3. 5 h in group 2 and 2. 6±1. 02 in group 3 (P<0. 001). Total requirement of analgesic (pethidine) in the first 48 h was 46±23. 69 in group 1. 34± 23 mg in group 2 and 54 ± 22. 7 mg in group 3 (P<0. 001). Pain score at 6h (VAS6) in the group 2 was significantly lower than the control group (5. 1±0/83 vs. 4/3 ±1/7; P<0. 005). Subcutaneous injection of bupivacaine 0. 5% (especially post operative) can be an effective method on post operative pain reduction، reduction of Pethidine consumption in the first 48 hour of operation and in increasing the time of the first analgesic requirement.