Ngan Kee Warwick D, Khaw Kim S, Ng Floria F, Lee Bee B
Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, China.
Anesth Analg. 2004 Mar;98(3):815-21, table of contents. doi: 10.1213/01.ane.0000099782.78002.30.
In a randomized, double-blinded, controlled trial, we investigated the prophylactic infusion of IV phenylephrine for the prevention of hypotension during spinal anesthesia for cesarean delivery. Immediately after intrathecal injection, phenylephrine was infused at 100 microg/min (n = 26) for 3 min. From that point until delivery, phenylephrine was infused at 100 microg/min whenever systolic arterial blood pressure (SAP), measured each minute, was less than baseline. A control group (n = 24) received IV bolus phenylephrine 100 microg after each measurement of SAP <80% of baseline. Phenylephrine infusion decreased the incidence (6 [23%] of 26 versus 21 [88%] of 24; P < 0.0001), frequency, and magnitude (median minimum SAP, 106 mm Hg; interquartile range, 95-111 mm Hg; versus median, 80 mm Hg; range, 73-93 mm Hg; P < 0.0001) of hypotension compared with control. Heart rate was significantly slower over time in the infusion group compared with the control group (P < 0.0001). Despite a large total dose of phenylephrine administered to the infusion group compared with the control group (median, 1260 microg; interquartile range, 1010-1640 microg; versus median, 450 microg; interquartile range, 300-750 microg; P < 0.0001), umbilical cord blood gases and Apgar scores were similar. One patient in each group had umbilical arterial pH <7.2. Prophylactic phenylephrine infusion is a simple, safe, and effective method of maintaining arterial blood pressure during spinal anesthesia for cesarean delivery.
In patients receiving spinal anesthesia for elective cesarean delivery, a prophylactic infusion of phenylephrine 100 microg/min decreased the incidence, frequency, and magnitude of hypotension with equivalent neonatal outcome compared with a control group receiving IV bolus phenylephrine.
在一项随机、双盲、对照试验中，我们研究了静脉输注去氧肾上腺素预防剖宫产脊髓麻醉期间低血压的效果。鞘内注射后立即以100微克/分钟的速度输注去氧肾上腺素（n = 26），持续3分钟。从那时起直至分娩，每当每分钟测量的收缩压（SAP）低于基线时，即以100微克/分钟的速度输注去氧肾上腺素。对照组（n = 24）在每次测量的SAP <基线的80%后静脉推注100微克去氧肾上腺素。与对照组相比，输注去氧肾上腺素降低了低血压的发生率（26例中的6例[23%]对24例中的21例[88%]；P < 0.0001）、频率和幅度（最低SAP中位数，106毫米汞柱；四分位间距，95 - 111毫米汞柱；对中位数80毫米汞柱；范围，73 - 93毫米汞柱；P < 0.0001）。与对照组相比，输注组的心率随时间显著减慢（P < 0.0001）。尽管与对照组相比，输注组给予的去氧肾上腺素总剂量较大（中位数，1260微克；四分位间距，1010 - 1640微克；对中位数450微克；四分位间距，300 - 750微克；P < 0.0001），但脐血血气和阿氏评分相似。每组各有1例患者脐动脉pH <7.2。预防性输注去氧肾上腺素是剖宫产脊髓麻醉期间维持动脉血压的一种简单、安全且有效的方法。
在接受择期剖宫产脊髓麻醉的患者中，与接受静脉推注去氧肾上腺素的对照组相比，预防性输注100微克/分钟的去氧肾上腺素可降低低血压的发生率、频率和幅度，且新生儿结局相当。
