Labor analgesia in parturients of fetal growth restriction having raised umbilical Doppler vascular indices

Background and Aims: Fetuses with abnormal umbilical blood flow are at a higher risk of adverse perinatal outcome than those with normal flow. Epidural analgesia (EA) has shown to decrease villous vascular resistance in preeclamptic women during labor. The present study evaluates the effects of epidural ropivacaine and intramuscular (IM) tramadol on Doppler blood flow in parturients with fetal growth restriction and raised umbilical artery (UmA) blood flow. Material and Methods: In this prospective nonrandomized comparative study, 36 term parturients with sonographic evidence of UmA systolic-diastolic (S-D) ratio ≥3 were enrolled. Parturients received either continuous epidural ropivacaine 0.2% or 1 mg/kg IM tramadol 4–6 hourly. Doppler flow parameters of UmA and bilateral uterine arteries (UtAs) were measured at 0, 1, and 6 h of labor analgesia. Doppler indices change with time during labor analgesia was assessed as the primary outcome. Change of Doppler indices of UtAs, Apgar score, and cord blood gases was considered as secondary measures. Results: Data from thirty laboring women who completed the study were analyzed. The pulsatility index, resistance index, and S-D ratio in UmA and right UtA reduced significantly with continuous epidural infusion during first 6 h of labor. However, these values increased or unchanged with tramadol administration. Better neonatal pH and base deficit (P = 0.039) were observed with EA. Conclusions: Continuous epidural ropivacaine causes improved fetoplacental circulation in parturients with growth-restricted fetuses having raised Doppler indices during labor analgesia. We also found better neonatal outcome with continuous infusion of epidural ropivacaine as compared to IM tramadol.