Anesthesia method and data collection
IRREGULAR UTERINE CONTRACTIONS, DECUBITUS, CONTRACTIONS
All parturients undergo labor analgesia after regular uterine contractions, and continue to apply analgesic pump until placental delivery (regular uterine contractions are defined as contractions every 2–3 min, and contractions last for more than 30 s). Ringer’s solution was infused before labor analgesia, and all parturients underwent fetal heart rate monitoring and LiDCO-rapid system monitoring.For the CSA group, parturients were placed in the left decubitus position. Continuous spinal anesthesia was given between L3 and 4, and the Pajunk continuous spinal anesthesia kit (Germany) was used to puncture the 21 G spinal anesthesia needle into the subarachnoid space, and a 3 cm catheter (25G) was placed on the head side. The first dose of ropivacaine 0.5 mg/ml + sufentanil 0.5 ug/ml within 5 ml in total, 15 min later, a continuous spinal analgesia pump was connected. The formula of the analgesic pump is 100 ml of ropivacaine 0.2 mg/ml + sufentanil 0.2 ug/ml, the background dose is 3 ml/h, the patient-controlled analgesia is 3 ml/time, and the lock time is 15 min.The parturients in the EA group were given continuous epidural anesthesia at the interval L3 to 4, and a 3 cm catheter was placed on the head side. The dose was ropivacaine 1 mg/ml + sufentanil 0.5ug/ml for a total of 5 ml, 5 min later, the same treatment was given for another time. The analgesic pump was connected after 15 min. The analgesic pump formula was 100 ml of ropivacaine 1 mg/ml + sufentanil 0.5ug/ml, a background dose of 5 ml/h, patient-controlled analgesia 5 ml/time, and a lock time of 15 min. The parturients were instructed to press the analgesic pump when VAS ≥ 4 to maintain VAS between 2 and 4 during labor. In both groups, the infusion was stopped after delivery of the placenta and the catheter was removed before the women returned to the ward.The LiDCO-rapid monitor was used throughout the labor process. The MAP, VAS score, CO and SVR were recorded at the time of regular uterine contraction(T