不同剂量去氧肾上腺素预防性泵注对腰麻下择期剖宫产产妇血流动力学的影响

Effects of prophylactic infusion of different-dose phenylephrine on maternal hemodynamics associated with spinal anesthesia for elective caesarean section

目的探讨不同剂量去氧肾上腺素预防性泵注对腰麻下择期剖宫产产妇血流动力学参数、恶心呕吐发生率的影响。方法择期剖宫产产妇150例，采用随机数字表法将产妇分为6组（每组25例）：去氧肾上腺素（0．1μg·kg-1·min-1）预防性泵注组（P1组）、去氧肾上腺素（0．2μg·kg-1·min-1）预防性泵注组（P2组）、去氧肾上腺素（0．3μg·kg-1．min-1）预防性泵注组（P3组）、去氧肾上腺素（0．4μg·kg-1．min-1）预防性泵注组（P4组）、对照组（C组）和麻黄碱预防性静脉注射组（E组）。腰麻完成平卧后，P1～P4组产妇分别即刻以0．1、0．2、0．3、0．4μg·kg-1．min-1速度静脉泵注去氧。肾上腺素10min，C组无预处理，E组平卧后即刻静脉注射麻黄碱10mg。采用无创血流监测仪监测产妇人室后即刻（T1）、麻醉前（T2）、麻醉后1min（T3）、麻醉后3min（T4）、麻醉后10min（T5）、胎儿娩出时（T6）的平均动脉压（meanarterialpressure，MAP）、心率（heartrate，HR）、心排血量（cardiacoutput，CO）、心指数（cardiacindex，CI）、胸液水平（thoracicfluidcontent，TFC）的变化；监测产妇术中胎儿娩出前恶心呕吐的发生情况。结果与C组、E组比较，去氧肾上腺素泵注组在T3、T4、T5时刻HR明显减慢（P〈0．05）。P4组在T6时刻心率明显减慢（P〈0．05）。R时刻P1、P2、P3组MAP均低于C组与E组（P〈0．05），P1组和P2组MAP均低于C组与E组约9％和4％，P3组低于C组与E组约为10％和5％。T6时刻P1组、P2组和P3组CO均高于c组（P〈0．05），分别增加了0．56、0．73L/min和0．61L／min。P3组、P4组升压药追加人数均低于C组、E组、P1组、P2组（P〈0．05）。P1组～P4组阿托品使用频次比较，差异无统计学意义（P〉0．05）。各组高血压的发生率比较，差异无统计学意义（P〉0．05）。P1组-P4组去氧肾上腺素平均泵注时间分别为（10．0±0．0）、（10．0±0．0）、（10．0±0．0）min和（9．6±0．7）min，P4组短干P1组、P2组、P3组（F=2．41，P〈0．05）。与E、C组比较，去氧肾上腺素泵注组恶心呕吐发生率显著降低（P〈0．05）。结论腰麻下行择期剖宫产术时预防性泵注去氧肾上腺素在维持血流动力学稳定、减少产妇恶心呕吐发生率方面较使用麻黄碱更有优势。而且0．3μg·kg-1．min-1～0．4μg·kg-1．min-1是腰麻下行择期剖宫产术时较为恰当的去氧肾上腺素预防性泵注速度。

Objective To assess the effects of prophylactic infusion of different-dose phenylephrine on maternal hemodynamics associated with spinal anesthesia for elective caesarean section. Methods One hundred and fifty women undergoing elective cesarean delivery under spinal anesthesia were divided into six groups by random number table （n=25）. The women in the four prophylactic phenylephrine infusion groups （P1 to P4 groups ） received a phenylephrine infusion respectively at the rates of 0.1, 0.2, 0.3 μg.kg-1.min-1 and 0.4 μg.kg-1.min-1 for 10 rain after spinal anesthesia. The women in the control group （C group） was not given with any prophylactic vasopressor infusion. The women in the ephedrine group （E group） was prophylactically injected intravenously with ephedrine 10 mg after spinal anesthesia. Heart rate （HR）, mean arterial pressure （MAP）, thoracic fluid content （TFC）, cardiac output （CO） and cardiac index （CI） were recorded by Noninvasive Heart Function Monitor （Solar 8000M） at baseline （T1）, before anesthesia （T2）, and l（T3）, 3 min （T4） and 10 min （T5） after anesthesia and delivery time （T6）. Incidence of nausea and vomiting also was recorded. Results Compared with C and E groups, HR at T3, T4 and T5 were decreased in the fourprophylactic phenylephrine infusion groups （P〈0.05）. HR at T6 was decreased in the P4 group （P〈0.05）. MAP at T6 was decreased in the P1, P2 and P3 groups （P〈0.05）, in P1, P2 groups MAP was decreased by 9% and 4%, in P3 group was decreased by 10% and 5%. CO at T6 was increased in the P1, P2 groups and P3 group （P〈0.05）, increased by 0.56, 0.73L/min and 0.61 L/min respectively. The number of additional vasopressor uses was less in the P3 group and P4 group than in the C, E, P1 group and P2 group （P〈0.05）. The number of additional atropine uses were not different among the four prophylactic phenylephrine infusion group （P〉0.05）. The incidence of hypertension were not different among the six groups （P〉0.05） . The average time of phenylephrine infusion were （10.0±0.0）, （10.0±0.0）, （10.0±0.0） rain and （9.6±0.7） min, in the P1 to P4 groups, respectively. The phenylephrine infusion time was significantly shorter in the P4 group than in the P1 to P3 groups （P〈0.05）. Compared with C and E groups, incidence of nausea and vomiting was significantly lower in the P1 to P4 groups （P〈0.05）. Conclusions Prophylactic infusion of phenylephrine was superior to the intravenous ephedrine on maintaining stable hemodynamics, and decreasing incidence of nausea and vomiting in women undergoing elective caesarean section under spinal anesthesia. Furthermore, a prophylactic infusion rate of phenylephrine of 0.3 μg. kg-1. min-1-0.4 μg. kg-1. min-1 can obtain the better clinical efficacy.