Hood D D, Dewan D M, James F M
Anesthesiology. 1986 May;64(5):610-3. doi: 10.1097/00000542-198605000-00011.
Intravenous cannulation by an epidural catheter may complicate epidural anesthesia. Local anesthetic solutions containing epinephrine produce tachycardia and hypertension when given intravenously and may identify intravenous placement. The authors studied the maternal and fetal effects of intravenous epinephrine-containing solutions in ten chronically instrumented gravid ewes. While continuously monitoring maternal and fetal effects, epinephrine 5, 10, or 20 micrograms iv bolus was injected. Solutions of bupivacaine 5 mg and bupivacaine 5 mg combined with epinephrine 10 micrograms given iv were also examined. All epinephrine-containing solutions produced a significant increase (P less than 0.001) in maternal mean arterial pressure, which returned to baseline after 1 min. Maternal heart rates decreased transiently and returned to baseline after 1 min. All epinephrine-containing solutions decreased uterine blood flow (UBF) (P less than 0.001), and, for doses of 10 to 20 micrograms, this decrease lasted more than 3 min. Fetal heart rate and mean arterial blood pressure did not change following any test solution, nor did maternal or fetal arterial blood gas values. The authors conclude that small intravenous boluses of epinephrine decreased UBF in these animals.
使用硬膜外导管进行静脉置管可能会使硬膜外麻醉复杂化。含肾上腺素的局部麻醉溶液静脉注射时会导致心动过速和高血压，这可能提示静脉置管。作者研究了含肾上腺素溶液静脉注射对10只长期植入仪器的妊娠母羊母体和胎儿的影响。在持续监测母体和胎儿影响的同时，静脉推注5、10或20微克肾上腺素。还检测了静脉注射5毫克布比卡因溶液以及5毫克布比卡因与10微克肾上腺素混合的溶液。所有含肾上腺素的溶液均使母体平均动脉压显著升高（P<0.001），1分钟后恢复至基线水平。母体心率短暂下降，1分钟后恢复至基线水平。所有含肾上腺素的溶液均使子宫血流量（UBF）降低（P<0.001），对于10至20微克的剂量，这种降低持续超过3分钟。任何测试溶液注射后，胎儿心率和平均动脉血压均未改变，母体或胎儿动脉血气值也未改变。作者得出结论，小剂量静脉推注肾上腺素会降低这些动物的子宫血流量。
