双侧胸椎旁神经阻滞与术后镇痛对非体外循环冠状动脉搭桥术患者应激反应的影响

Effect of bilateral thoracic paravertebral block and postoperative analgesia on stress response in patients undergoing off-pump coronary artery bypass grafting

目的探讨双侧胸椎旁神经阻滞与术后镇痛对非体外循环冠状动脉搭桥术患者应激反应的影响。方法择期非体外循环冠状动脉搭桥术患者50例，随机分为两组：双侧胸椎旁神经阻滞复合全麻组（P组）和单纯全麻组（G组），每组25例。P组患者麻醉诱导前经T3～T4间隙行双侧胸椎旁间隙穿刺置管，术后镇痛经两侧硬膜外导管分别持续泵入0．375％罗哌卡因5ml／h。G组患者用吗啡静脉自控镇痛。记录镇痛开始后12、24、36和48h疼痛VAS评分及镇静程度评分；观察术后并发症及不良反应；于麻醉前、术毕、术后24及48h抽取静脉血，测定血浆胰岛素、皮质醇及血管紧张素Ⅱ（ATⅡ）浓度。结果P组患者镇痛后各时间点时安静痛、咳嗽痛VAS评分及镇静程度Ramsay评分均显著低于G组（P〈0．05）。与麻醉前比较，两组患者胰岛素、皮质醇及ATⅡ水平术毕均升高（P〈0．05），P组患者术后24~48h降至正常水平。与G组比较，术毕、术后24及48h胰岛素、皮质醇及ATⅡ水平均低于G组（P〈0．05）。结论双侧胸椎旁神经阻滞与术后镇痛可一定程度上抑制非体外循环冠状动脉搭桥术患者应激激素释放。

Objective To investigate the effect of bilateral thoracic paravertebral block and postoperative analgesia on stress response in patients undergoing off-pump coronary artery bypass grafting. Methods Fifty patients scheduled for off-pump coronary artery bypass grafting, were randomly divided into two groups（n=25 each）： bilateral thoracic paravertebral block combined with general anesthesia group （group P） and pure general anesthesia group（group （3）. Bilateral thoracic paravertebral block and insertion epidural catheter were performed at T3-4 interspace and an infusion of 0.375% ropivacacine was injected at the rate of 5 ml/h up to 48h at the end of the operation in group P. The patients in group G received PCIA with morphine. VAS scores of rest pain, cough pain and sedation score were recorded at 12, 24, 36 and 48 hours after postoperative analgesia beginning. Complications and side effects after operation were recorded. Blood samples were taken to determine the serum insulin, cortisol and angiotensinⅡconcentrations before anesthesia, at the end of operation, postoperative 24 and 48 h respectively. Results VAS scores of rest pain, cough pain and sedation score in group P were significantly lower than in group G at the four points（P〈0.05）. The levels of insulin, cortisol and angiotensin Ⅱ at the end of operation were higher than before anesthesia（P〈0.05） and declined to normal levels at postoperative 24 or 48 h in group E Compared with group G, the levels of insulin, cortisol and angiotensin Ⅱ were significantly lower in group P at the end of operation, postoperative 24 and 48 h respectively（P〈0.05）. Conclusion Bilateral thoracic paravertebral block and postoperative analgesia could decrease the level of stress hormone in patients undergoing off-pump coronary artery bypass graiting.