Powell Mark F, Morgan Charity J, Cantu Jessica A, Sakawi Yasser, Biggio Joseph R, Tita Alan T N, Szychowski Jeff M, Edwards Rodney K
Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama.
Am J Perinatol. 2017 Jun;34(7):716-721. doi: 10.1055/s-0036-1597847. Epub 2016 Dec 28.
Our aims were to evaluate whether there is an inverse association between body mass index (BMI) and umbilical artery pH and to investigate the contribution of intraoperative hypotension on the umbilical artery pH. We conducted a retrospective cohort study of all women with a nonanomalous singleton at 37 to 41 weeks who underwent a scheduled cesarean delivery under spinal anesthesia at our facility from January 2006 to March 2012. The primary outcome was the proportion of patients in each BMI category with arterial cord pH < 7.10. Intraoperative blood pressure data were compared across BMI categories. In total, 717 mother-infant pairs met enrollment criteria. Mean arterial pH was significantly lower in women with elevated BMI ( = 0.014), notably with BMI ≥ 40 kg/m. Baseline blood pressure increased linearly with increasing BMI ( < 0.001), however, so did the maximum drop in all blood pressure parameters ( < 0.001). After adjusting for potential confounders, including blood pressure, there was no longer an association between cord pH and BMI ( = 0.72). For women undergoing a scheduled cesarean delivery under spinal anesthesia, umbilical artery pH is lower in women with BMI ≥40 kg/m. Relative hypotension after spinal anesthesia is more pronounced with increasing BMI and may explain this effect.
我们的目的是评估体重指数（BMI）与脐动脉pH值之间是否存在负相关，并研究术中低血压对脐动脉pH值的影响。我们对2006年1月至2012年3月在我们机构接受脊髓麻醉下择期剖宫产的所有37至41周单胎非畸形孕妇进行了一项回顾性队列研究。主要结局是各BMI类别中动脉血脐带pH值<7.10的患者比例。比较了不同BMI类别之间的术中血压数据。总共717对母婴符合纳入标准。BMI升高的女性平均动脉pH值显著较低（P = 0.014），尤其是BMI≥40kg/m²的女性。基线血压随BMI升高呈线性增加（P<0.001），然而，所有血压参数的最大降幅也是如此（P<0.001）。在调整包括血压在内的潜在混杂因素后，脐带pH值与BMI之间不再存在关联（P = 0.72）。对于接受脊髓麻醉下择期剖宫产的女性，BMI≥40kg/m²的女性脐动脉pH值较低。脊髓麻醉后的相对低血压随着BMI的增加而更加明显，这可能解释了这种效应。
