The Clinical Study Of Combined Spinal-epidural Anesthesia, Nitrous Oxide Inhalation And Remifentanil PCA For Labor Analgesia

Objective:To evaluate the clinical effect of combined spinal-epidural epidural anesthesia, nitrous oxide inhalation and remifentanil patients-controlled analgesia (PCA) on the duration of labor analgesia and to further clarify the influence to the maternal, fetal and neonate in the different labor analgesia mode.Methods:120 women (ASAI or GradeⅡ) without contraindications of obstetrics and spinal block and with first single baby head-located down were selected and classified into four groups randomly:A: Sufentanil+Ropivacaine combined spinal epidural anesthesia (CSEA); B: Nitrous oxide inhalation; C:Remifentanil Intravenous infusion; D: Control group without analgesia. All the women had no head disproportion, pregnancy complications, and were diagnosed through vaginal delivery by the obstetrician. When the cervix was open by 3cm, group A was subjected to ropivacaine 1.5 mg+sufentanil 2.5μg+0.9% saline 2 ml through subarachnoid injection.(?)1.1% epidural ropivacaine and 0.187μg/ml sufentanil were added to patients-controlled epidural analgesia (PCEA). The first dose is 7 ml/h, the basical injection speed is 6 ml/h, the bolus of volume is 6 ml, the maximum speed is 27 ml/h and local time is 15 min. Group B was subject to nitrous oxide (50% nitrous oxide and 50% oxygen). Group C was subjected to remifentanil PCA pump. Group D was the control group with no analgesia intervention. All the treatment were stopped when cervix was open completely. Visual analogue pain score (VAS), maternal lower limb motor block score (MBS), vital signs, patients satisfaction, side effects, complications, labor time, the amount of oxytocin, mode of delivery, postpartum hemorrhage, fetal and newborn child situation were recorded.Results:Three methods of analgesia could provide safe and effective analgesia. The degree of pain in order was the group A, group C, group B and group D. The labor time were shorted in the group A and B compared with the group C. The active phase of group A was shorter than that of the group B, group C and group D (127.54±60.693 min vs 166.76±59.530 min,258.67±71.940 min and 207.59±68.039 min, all P<0.05). The expulsive stages had no significant difference in all groups. Compared with the group D (43.3%), the rates of uterine-incision delivery were decreased significantly (respectively 13.3%,16.7%and 20.0%,all P<0.05). MBS had no significant difference in all groups (all P>0.05). All maternal women after labor could go around in the room in three groups. The rates of fetal distress in uterus, apnoea neonatorum and postpartum hemorrhage had no significant difference in all groups (all P>0.05). Compared with group D, the satisfaction degree of postnatal recovery in group A, B and C were increased significantly (all P<0,05). Compared with group B and C the satisfaction degree of postnatal recovery in group A was increased significantly (P<0.05).Conclusions:CSEA+ PCEA with Sufentanil and Ropivacaine combined, nitrous oxide inhalation and remifentanil PCA all relive significantly the puerperal pain, decrease significantly the cesarean rate, and also provid safety for puerperal, fetal and newborn child.In this experimental conditions, remifentanil PCA doesn't shorten labor time. CSEA is more effective by shortening the birth process and more suitable for labor analgesia compared to remifentanil and nitrous oxide analgesia.