Ngan Kee Warwick D, Khaw Kim S
Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Prince of Wales Hospital Shatin, Hong Kong, China.
Curr Opin Anaesthesiol. 2006 Jun;19(3):238-43. doi: 10.1097/01.aco.0000192816.22989.ba.
Historically, ephedrine has been recommended as the best vasopressor in obstetrics because animal studies showed it caused less reduction in uterine blood flow compared with alpha-agonists. Recent clinical evidence, however, suggests that this is not as important as initially thought. This review evaluates current data with a focus on spinal anesthesia for cesarean section.
Ephedrine and phenylephrine have been most investigated. Advantages of ephedrine include familiarity, long history and low propensity for uteroplacental vasoconstriction. Ephedrine, however, has limited efficacy, is difficult to titrate, causes maternal tachycardia and depresses fetal pH and base excess. Advantages of phenylephrine include high efficacy, ease of titration and the ability to use liberal doses to maintain maternal blood pressure near normal and then prevent nausea and vomiting without causing fetal acidosis. Phenylephrine, however, may decrease maternal heart rate and cardiac output and few data are available on its use in high-risk cases. Combination of a phenylephrine infusion and rapid crystalloid cohydration is the first method described that reliably prevents hypotension.
When current evidence is considered, in the authors' opinion, phenylephrine is the vasopressor that most closely meets the criteria for the best vasopressor in obstetrics.
从历史上看，麻黄碱一直被推荐为产科最佳血管升压药，因为动物研究表明，与α受体激动剂相比，它引起的子宫血流减少较少。然而，最近的临床证据表明，这并不像最初认为的那么重要。本综述评估了当前的数据，重点是剖宫产的脊髓麻醉。
对麻黄碱和去氧肾上腺素的研究最多。麻黄碱的优点包括为人熟知、历史悠久以及子宫胎盘血管收缩倾向低。然而，麻黄碱疗效有限、难以滴定、会导致母体心动过速并降低胎儿pH值和碱剩余。去氧肾上腺素的优点包括高效、易于滴定以及能够使用大剂量来维持母体血压接近正常水平，进而预防恶心和呕吐，且不会导致胎儿酸中毒。然而，去氧肾上腺素可能会降低母体心率和心输出量，关于其在高危病例中的应用数据较少。去氧肾上腺素输注与快速晶体液补液相结合是第一种被描述的可靠预防低血压的方法。
在作者看来，考虑到当前的证据，去氧肾上腺素是最符合产科最佳血管升压药标准的血管升压药。
