预负荷/共同负荷联合血管收缩药在剖宫产术中对母婴血气的影响

目的探讨预负荷/共同负荷联合血管收缩药在剖宫产术中对产妇和新生儿血气的影响。方法将择期剖宫产产妇（ASA I～Ⅱ）,在排除酸中毒（pH〈7.35或BE〈-6）或碱中毒（pH〉7.45或BE〉6）后,随机分为麻黄素组（E组）和去氧肾上腺素组（P组）,每组30例。两组预负荷晶体液乳酸钠林格氏液6～8ml/kg,穿刺到硬膜外间隙时,分别静脉给予麻黄素5mg、去氧肾上腺素100μg。腰麻注药后,两组均输入羟乙基淀粉130/0.4氯化钠溶液10ml/kg（共同负荷）,并分别静脉泵注麻黄素和去氧肾上腺素。观察记录两组产妇的BP、HR、ECG、SpO2,至胎儿娩出即刻查母体和脐动脉血血气,记录新生儿出生后第1min及第5min时的Apgar评分。结果 P组脐动脉血pH、BE值均高于E组（P〈0.05）。结论预负荷/共同负荷联合血管收缩药能有效减少腰麻后低血压的发生,维持产妇血流动力学稳定。去氧肾上腺素比麻黄素能更好地减少新生儿酸中毒的发生。

Effects of preload/coload combined with vasoconstrictor in cesarean section on the blood gas of parturient and the newborn

Objective To investigate the effects of preload/coload combined with vasoconstrictor on the blood gas of parturient and the newborn in the cesarean section.Methods Those parturients of elective cesarean section(ASA class Ⅰ~ Ⅱ) without acidosis(pH<7.35 or BE<-6) or alkalosis(pH>7.45 or BE>6) were randomly divided into two groups:phenylephrine group(group P) and ephedrine group(group E) with 30 cases each.The values of maternal BP,HR,ECG,SpO2 were recorded.Lactated Ringer’s solution was injected before induction of spinal anesthesia with 6~8 ml/kg in 20~30 min(proload).The two groups were respectively given ephedrine 5 mg or phenylephrine 100 μg intravenously while puncture needle reachered the epidural space.Hydroxyethyl Starch 130/0.4 and Sodium Chloride solution was injected after spinal anesthesia with 10 ml/kg in both groups(coload),and,ephedrine or phenylephrine was given continuously with pump injection intravenously.The pump didn’t stop until the neonate was born.The blood gas analysis of maternal arterial blood and umbilical arterial blood was done immediately after the birth.The Apgar score was recorded at the time of 1 min and 5 min after neonate was born.Results The values of pH and BE of umbilical arterial blood in group P were higher than those in group E(P<0.05).Conclusion Preload/coload combined with vasoconstrictor can effectively decrease the incidence of maternal hypotension after spinal anesthesia and maintain maternal hemodynamic stability.However,phenylephrine can better reduce the incidence of acidosis on the newborn than ephedrine.