Department of Anaesthesiology, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University, Qingdao, P. R. China.
Medicine (Baltimore). 2024 Mar 8;103(10):e37454. doi: 10.1097/MD.0000000000037454.
Phenylephrine may cause a reduction in maternal cerebral tissue oxygen saturation (SctO2) during Caesarean birth to prevent spinal hypotension; however, the effect of norepinephrine has not been assessed. We hypothesized that norepinephrine was more effective than phenylephrine in maintaining SctO2 when preventing spinal hypotension during Caesarean birth.
We conducted a randomized, double-blind, controlled study. Sixty patients were randomly assigned to prophylactic norepinephrine or phenylephrine to maintain blood pressure during spinal anesthesia for Caesarean birth. SctO2, systolic blood pressure, and heart rate were recorded. The primary outcome was the incidence of a 10% reduction of intraoperative SctO2 from baseline or more during Caesarean birth.
The norepinephrine group had a lower incidence of more than 10% reduction of intraoperative SctO2 from baseline than that of the phenylephrine group (13.3% vs 40.0%, P = .02). The change in SctO2 after 5 minutes of norepinephrine infusion was higher than that after phenylephrine infusion (-3.4 ± 4.7 vs -6.2 ± 5.6, P = .04). The change in SctO2 after 10 minutes of norepinephrine infusion was higher than that after phenylephrine infusion (-2.5 ± 4.4 vs -5.4 ± 4.6, P = .006). The norepinephrine group showed greater left- and right-SctO2 values than the phenylephrine group at 5 to 10 minutes. However, the change in systolic blood pressure was comparable between the 2 groups.
Norepinephrine was more effective than phenylephrine in maintaining SctO2 when preventing spinal hypotension during Caesarean birth. However, the changes in clinical outcomes caused by differences in SctO2 between the 2 medications warrant further studies.
在剖宫产术中，去氧肾上腺素可通过减少产妇脑氧饱和度（SctO2）来预防脊髓低血压，但去甲肾上腺素的作用尚未得到评估。我们假设，在预防剖宫产术中脊髓低血压时，去甲肾上腺素比去氧肾上腺素更能有效维持 SctO2。
我们进行了一项随机、双盲、对照研究。将 60 名患者随机分为预防性去甲肾上腺素或去氧肾上腺素组，以维持脊髓麻醉下剖宫产期间的血压。记录 SctO2、收缩压和心率。主要结局是术中 SctO2 从基线下降 10%或更多的发生率。
与去氧肾上腺素组相比，去甲肾上腺素组术中 SctO2 从基线下降超过 10%的发生率较低（13.3% vs 40.0%，P=0.02）。去甲肾上腺素输注 5 分钟后的 SctO2 变化高于去氧肾上腺素输注后的变化（-3.4±4.7 vs -6.2±5.6，P=0.04）。去甲肾上腺素输注 10 分钟后的 SctO2 变化高于去氧肾上腺素输注后的变化（-2.5±4.4 vs -5.4±4.6，P=0.006）。去甲肾上腺素组在 5 至 10 分钟时的左、右侧 SctO2 值均高于去氧肾上腺素组。然而，两组间收缩压的变化相当。
在预防剖宫产术中脊髓低血压时，去甲肾上腺素比去氧肾上腺素更能有效维持 SctO2。然而，两种药物之间 SctO2 差异引起的临床结局变化需要进一步研究。
