全麻诱导期快速输液对腹部手术病人血液动力学的影响

Hemodynamic response to rapid plasma volume expansion in patients scheduled for abdominal surgery during induction of general anesthesia

目的比较晶体液和胶体液快速扩容对全麻诱导期腹部手术病人血液动力学的影响。方法ASAⅠ-Ⅱ级择期行腹部手术病人60例,随机分为3组(n=20)。A组于诱导开始时。以15ml·kg1·h-1匀速输入乳酸钠林格氏液;B和C组于诱导前20min内开始分别输入7ml·kg-1乳酸钠林格氏液和6％羟乙基淀粉,诱导开始时加快输液速度,20min内分别输入13ml·kg-1乳酸钠林格氏液和6％羟乙基淀粉。结果麻醉诱导后及插管后A组收缩压低于B组和C组(P<0.01)。中心静脉压随输液量的增加而渐升高,升高幅度C组>B组>A组(P<0.05)。麻醉诱导后,A组心脏指数(CI)开始下降,气管插管后仍低于基础值;B和C组诱导后CI稍增加,气管插管后B组渐降至低于基础值,但下降幅度小于A组,而C组无明显变化。外周血管阻力(SVR)变化与CI相反,A和B组麻醉诱导及气管插管后SVR较基础值增加或变化不明显,而C组下降(P<0.05))。升主动脉血液加速度指数麻醉诱导及气管插管后A组无明显变化,B组诱导后增加,气管插管后降至基础值水平,而C组诱导及气管插管后均较基础值升高(P<0.05或0.01)。结论晶体液和胶体液快速扩容对全麻诱导期低血压有相似的预防作用,但预防CI下降的作用胶体液优于晶体液。

Objective To compare the hemodynamic response to rapid plasma volume expansion with crystalloid and colloid during induction of general anesthesia. Methods Sixty ASA Ⅰ - Ⅱ patients of both sexes (36 male, 24 female) aged 22-65 yr undergoing elective major abdominal surgery were randomly allocated to one of 3 groups (A, B, C) 20 in each group receiving either crystalloid or colloid. The patients were unpremedicated The patients were sedated with intravenous midazolam 0.04 mg·kg-1' . Radial artery and right internal jugular vein were cannulated under local infiltration for BP and CVP monitoring. ECG, SpO2 and PET CO2 were continuously monitored during anesthesia. Cardiac function was monitored by impedance cardiogaphy. Anesthesia was induced with fentanyl 3 μg·kg-1 , propofol 1.6 mg·kg-1 in divided doses and vecuronium 0.1 mg·kg-1 . After tracheal intubation the patients were mechanically ventilated and PETCO2 was maintained at 35-40 mm Hg. Anesthesia was maintained with isoflurane and intermittent i.v. doses of fentanyl and vecuronium. In group A lactated Ringer's solution (RL) was infused at 15 ml · kg-1· h-1 as soon as induction of anesthesia was started. In group B and C RL (B) or 6% hydroxyethyl starch (HES) (C) 7 ml·kg-1 was infused in 20 min before induction of anesthesia. As soon as induction was started another 13 ml·kg-1 of RL or HES was infused in 20 min. Results (1) The SBP was significantly lower in group A than in group B and C and the HR was not significantly different among the 3 groups. (2) The CVP gradually increased with fluid infusion. The degree of increase was in the order of C>B>A ( P < 0 05) (3) The cardiac index (CI) began to decrease after induction and was still lower than the baseline after intubation in group A while in group B and C CI increased slightly after induction and then gradually decreased to the level lower than the baseline in group B, but was maintained at baseline level in group C. (4) The systemic vascular resistance (SVR) slightly increased or was unchanged in group A and B but was significantly decreased in group C after induction and intubation. (5) The acceleration index (ACI) slightly decreased after induction and intubation in group A whereas in group B significantly increased after induction then gradually returned to the baseline level after intubation, but in group C ACI significantly increased after induction and intubation. Conclusion The effect of rapid plasma volume expansion with crystalloid or colloid on prevention of hypotension during induction is similar but colloid is better in prevention of CI decrease.