MULTIMODAL ANALGESIA BEFORE THORACIC-SURGERY DOES NOT REDUCE POSTOPERATIVE PAIN

Several reports have suggested that preoperative nociceptive block may reduce postoperative pain, analgesic requirements, or both, beyond th e anticipated duration of action of the analgesic agents. We have inve stigated, in a double-blind, placebo-controlled study pre-emptive anal gesia and the respiratory effects of preoperative administration of a multimodal antinociceptive regimen. Thirty patients undergoing thoraco tomy were allocated randomly to two groups. Before surgery, the treatm ent group (n = 15) received morphine 0.15 mg kg(-1) i.m. with perphena zine 0.03 mg kg(-1) i.m. and a rectal suppository of indomethacin 100 mg, while the placebo group (n = 15) received midazolam 0.05 mg kg(-1) i.m. and a placebo rectal suppository. After induction of anaesthesia , the treatment group received intercostal nerve block with 0.5% bupiv acaine and adrenaline 1:200000 (3 ml) in the interspace of she incisio n and in the two spaces above and two spaces below. The placebo group received identical injections but with normal saline only. The treatme nt group consumed significantly less morphine by patient-controlled an algesia in the first 6 h after operation, but the total dose of morphi ne consumed on days 2 and 3 after surgery was significantly greater in the treatment group. There were no differences between the groups in postoperative VAS scores (at rest or after movement), Pa-CO2 values or postoperative spirometry. However, pain thresholds to pressure applie d at the side of the chest contralateral to the site of incision decre ased significantly from preoperative values on days 1 and 2 after surg ery in both groups. The results of this study do not support She preop erative use of this combined regimen for post-thoracotomy pain.