尼卡地平控制性降压联合中度高容量血液稀释对内脏氧合及全身炎性反应的影响

The effects of combination of nicardipine-induced hypotension with moderate hypervolemic hemodilution on the visceral oxygenation and systemic inflammatory responses

目的研究尼卡地平控制性降压联合中度急性高容量血液稀释（AHH）对内脏氧合及全身炎性反应的影响。方法神经外科病人10例，麻醉诱导后30min内行中度AHH，使红细胞压积（Hct）降至30％，术中采用尼卡地平控制性降压，并维持MAP在55～65mmHg。观察入室（T0）、血液稀释至目标值（T1）、控制性降压至目标值（T2）、降压达目标值后30min（T3）、降压停止（T4）和术毕（T5）时胃粘膜二氧化碳分压（PgCO2）、PgCO2与动脉血二氧化碳分压差（Pg-aCO2）、胃粘膜pH值（i-pH），测定T1、T3和T5时血清肿瘤坏死因子α（TNF-α）、白细胞介素-8（IL-8）和β2-微球蛋白（β2-MG）含量。结果T1、T2、T5时的i-pH与T0时相比显著降低（P〈0．05），T1、T2、T3时的Pg-aCO2与T0时相比明显升高（P〈0．05）。T4、T5时的血乳酸（Lac）水平明显高于T0时（P〈0．05）。各时点的TNF-α含量较正常值明显增加（P〈0．05），而IL-8和β2—MG含量无显著改变。结论中度AHH可能会导致内脏氧合受损，并激发全身炎性反应，联合尼卡地平控制性降压可部分缓解内脏氧合受损和全身炎性反应。

Objective To investigate effects of moderate acute hypervolemic hemodilution combined with induced hypotension by nicardipine on visceral oxygenation and systemic inflammatory response. Methods Ten patients undergoing neurosurgery were randomly selected. AHH was executed and finished within 30 min after anesthesia induction, and the hemocrit （Hct） was diluted to 30 %. Nicardipine-induced hypotension was executed during operation, and MAP was maintained at 55- 65mmHg, The PgCO2 ,Pg-αCO2 and i-pH were measured and recorded individually at before anesthesia induction （T0）, hemodiluted-Hct to target （30%） （T1）, induced hypotension to target MAP （T2）, 30 min following induced hypotension to target MAP （T3）, the end of induced hypotension （T4） and the end of operation （T5）. At T1, T2, T3, tumor necrosis factor-α （TNF-α）, Interleukin-8 （IL-8） and β2-microglobulin（β2-MG） were measured. Results The i-pH at T1,T2,T3 were much lower than that at To （P〈0. 05） ,and the Pg-αCO2 at T1 ,T2 and T3 were significantly increased compared with that at To （P〈0.05）. The content of arterial lactate at T4 ,T5 were much higher than that at To （P〈0. 05）. The serum level of TNF-α at T1 ,T2 and T3 were obviously elevated beyond the nor- mal range, but IL-8 and β2-MG had no remarkably changed. Conclusion Moderate acute hypervolemic hemodilution possibly leads to the damage of visceral oxygenation and activate the systemic inflammatory responses. These consequences could be partly relieved by combined nicardipine-induced hypotension, but not totally reversed.