Department of Obstetrics and Gynecology, Marche Polytechnic University, Ancona, Italy.
Department of Clinical Sciences, Polytechnic University of Marche Salesi Hospital, via Corridoni 11, 60123, Ancona, Italy.
Arch Gynecol Obstet. 2023 Jun;307(6):1789-1794. doi: 10.1007/s00404-022-06658-2. Epub 2022 Jun 15.
To analyze the mechanisms involved in the fetal heart rate (FHR) abnormalities after the epidural analgesia in labor.
A prospective unblinded single-center observational study on 55 term singleton pregnant women with spontaneous labor. All women recruited underwent serial bedside measurements of the main hemodynamic parameters using a non-invasive ultrasound system (USCOM-1A). Total vascular resistances (TVR), heart rate (HR), stroke volume (SV), cardiac output (CO) and arterial blood pressure were measured before epidural administration (T0), after 5 min 5 (T1) from epidural bolus and at the end of the first stage of labor (T2). FHR was continuously recorded through computerized cardiotocography before and after the procedure.
The starting CO was significantly higher in a subgroup of women with low TVR than in women with high-TVR group. After the bolus of epidural analgesia in the low-TVR group there was a significant reduction in CO and then increased again at the end of the first stage, in the high-TVR group the CO increased insignificantly after the anesthesia bolus, while it increased significantly in the remaining part of the first stage of labor. On the other hand, CO was inversely correlated with the number of decelerations detected on cCTG in the 1 hour after the epidural bolus while the short-term variation was significantly lower in the group with high-TVR.
Maternal hemodynamic status at the onset of labor can make a difference in fetal response to the administration of epidural analgesia.
分析分娩时硬膜外镇痛后胎儿心率（FHR）异常的机制。
对 55 例足月单胎自发性分娩的孕妇进行前瞻性、非盲、单中心观察性研究。所有入组的孕妇均使用非侵入性超声系统（USCOM-1A）连续床边测量主要血流动力学参数。在硬膜外给药前（T0）、硬膜外推注后 5 分钟 5 秒（T1）和第一产程结束时（T2）测量总血管阻力（TVR）、心率（HR）、每搏量（SV）、心输出量（CO）和动脉血压。在操作前后通过计算机胎儿心电图连续记录 FHR。
低 TVR 组的起始 CO 明显高于高 TVR 组。在低 TVR 组，硬膜外镇痛推注后 CO 显著降低，然后在第一产程结束时再次升高，在高 TVR 组，麻醉推注后 CO 增加不明显，而在第一产程的其余部分则显著增加。另一方面，CO 与硬膜外推注后 1 小时 cCTG 上检测到的减速次数呈负相关，而在高 TVR 组，短期变异明显较低。
分娩开始时产妇的血流动力学状态可能会影响胎儿对硬膜外镇痛的反应。
