肠道在休克早期时极易发生损伤,因此被认为是多器官功能衰竭的始动器官[7]。在全身血流动力学及氧代谢改善后,尤其关注肠道灌注。Pg-aCO2和pHi是反应肠道缺血缺氧的敏感指标,Pg-aCO2的升高和pHi降低表明肠道组织存在缺氧、低灌注。而粘膜的酸中毒、粘膜的损伤必然增加粘膜的通透性,增加肠道细菌和毒素的移位,最终可能导致多器官功能衰竭[8,9]。因此,休克时pHi值的监测显得尤为重要,休克复苏需以恢复pHi为治疗目标[10]。本研究结果显示,HES组在液体复苏后60、120min 肠道血流明显升高,同时伴有Pg-aCO2的降低和pHi明显上升,而RS组复苏后Pg-aCO2仍然明显升高,pHi呈下降趋势,显著低于同时期HES组。强烈提示HES较RS可以更好的改善内脏灌注,而这种效应与CI和DO2的提高无明显关系,可能与肠道血流重新分布有关[6]。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> 值得注意的是,全身血流动力学的恢复不代表组织缺氧状态的纠正。本研究显示,两组动物在液体复苏后即使血压、CI及DO2都明显恢复,但反映内脏灌注的Pg-aCO2和pHi并没有恢复到模型前水平,表明虽然积极液体复苏,组织缺氧未能纠正。这与Silva的研究一致[11]。其可能的原因是本研究中液体复苏的量不够,还需要继续补充血容量,其次是休克发生后肠道血流重分布已经发生,液体复苏短期内不能逆转,还可能与肠道血流恢复后再灌注损伤有关。 总之,积极的液体复苏有利于纠正感染性休克血流动力学紊乱。在纠正全身血流动力学紊乱的同时,应关注内脏的灌注,以利于休克的根本纠正。与RS液比较,HES可能更有利于内脏灌注的改善。 参考文献 1. River E, Nguyen B, Havstad S, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med, 2001, 345: 1368-1377. 2. Fiddian-Green RG. Associations between intramucosal acidosis in the gut and organ failure. Crit Care Med, 1993, 21(Suppl): 103-7. 3. Fink MP, Heard SO. Laboratory models of sepsis and septic shock. J Surg Res, 1990, 49: 186-96. 4. Marx G, Pedder S, Smith L, et al. Resuscitation from septic shock with capillary leakage: hydroxyethyl starch, but not RS’s solution maintains plasma volume and systemic oxygenation. Shock, 2004, 21: 336-341. 5. Haglund U, Fiddian-Green RG. Assesment of adequate tissue oxygenation in shock and critical illness: Oxygen transport in sepsis. Intensive Care Med, 1989, 15: 475-7. 6. 杨毅, 邱海波, 谭焰, 等. 多巴酚丁胺联用去甲肾上腺素和多巴胺对感染性休克绵羊内脏灌注的影响. 中国危重病急救医学, 2003, 15: 658-661. 7. Lagoa CA, Figueiredo LFP, Jr RJZ, et al. Effect of volume resuscitation on splanchnic perfusion in canine model of severe sepsis induced by live Escherichia coli infusion. Critical Care, 2004, 8: R221-R228. 8. Levy B, Gawalkiewicz P, Vallet B, et al. Gastric capnometry with air-automated tonomety predicts outcome in critically ill patients.Crit Care Med, 2003, 31: 474-480. 9. 王忠堂,姚咏明,肖光夏,等.双歧杆菌对烫伤大鼠肠道粘膜机械及生物屏障的改善作用.中国危重病急救医学, 2003, 15: 154-158. 10. Fiddian-Green RG, Haglund U, Guillermo G, et al. Goals for the resuscitation of shock. Crit Care Med, 1993, 21 (Suppl): 25-31. 11. Silva E, Backer DD, Creteur J, et al.Effect of fluid challenge on gastric mucosal PCO2 in septic shock.Intensive Care Med, 2004, 30: 423-429. |