[Effect and safety of electroacupuncture analgesia at the latent stage of labor on the epidural analgesia].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) analgesia at the latent stage of labor on epidural analgesia, labor outcome and neonatal score so as to provide the reference to the clinical labor analgesia. METHODS: According to the random number table, 104 primipara of vaginal delivery were divided into three groups, named an EA group (37 cases), a sham-EA group (36 cases) and an epidural block group (31 cases). In the EA group, when the cervix opened up by 1 cm, Han's acupoint nerve stimulation apparatus was attached to bilateral Hegu (LI4) and bilateral Sanyinjiao (SP6) to achieve EA analgesia till the active stage (the cervix up 3 cm). In the sham-EA group, the procedure was same as the EA group, but with the sham-stimulation. In the epidural block, EA was not used in intervention. When the cervix opened up 3 cm, the epidural block and the patient-controlled epidural analgesia were all adopted in each group. The score of visual analogue scale (VAS) and the dosage of Sufentanil and Ropivacaine in patient-controlled analgesia pump at the different time points were compared among the groups. Respectively, in 1 h of EA stimulation (T1), 2 h of EA stimulation (T2), at the moment of epidural block (T3) and the complete open of the cervix (T6), the venous blood sample was collected to determine the concentration of beta-endorphin (beta-EP), and the use time of oxytocin, the bleeding amount and the state of newborn were recorded. RESULTS: There was no statistical difference in immediate of EA stimulation (T0) among the groups in VAS score (P>0.05). But, in T1 to T6, VAS score in the EA group was reduced obviously as compared with the sham-EA group and the epidural block group separately (P<0.05). There was no statistical difference in the use time of oxytocin among the three groups (P>0.05). In the sham-EA group and the epidural block group, bleeding amount during labor and in 24 h after labor was all higher than that of the EA group (P<0.05). In each group, the concentration of beta-EP in T3 and T6 was increased obviously as compared with that in T1 and T2 respectively (P<0.05). In the EA group, the concentration of beta-EP in T1 to T3 and in T6 was higher than that in sham-EA group and the epidural block group respectively (P<0.05). The dosage of Ropivacaine and Sufentanil in the EA group was less than that in either the sham-EA group or the epidural block group (P<0.05). There was no significant difference in amniotic fluid turbidity rate and Apgar score among the three groups (P>0.05). CONCLUSION: Electroacupuncture analgesia at the latent stage of labor effectively relieves labor pain of primipara, increases the concentration of beta-EP, enhances the effect of epidural block analgesia, reduces labor bleeding and has no side effect on newborn. The combination of electroacupuncture analgesia and the epidural anesthesia in the latent stage is applicable in the whole process of labor.

[Effect of preemptive electroacupuncture on pain reactions in primiparous parturients during vaginal delivery].

OBJECTIVE: To investigate the effect of preemptive electroacupuncture (EA) plus epidural block (EB) on pain reactions and stress hormone levels in primiparous parturients during labor. METHODS: A total of 104 primiparous parturients undergoing vaginal delivery were randomly divided into PA group (n=31), sham EA group (n=36) and EA group (n=37). EA (2 Hz/100 Hz, a tolerable strength) was applied to bilateral Hegu (LI4) and Sanyinjiao (SP6) beginning from the latency of the 1st birth process when the orifice of uterus was opened to about 1 cm wider till the active stage when the orifice of the uterus opened about 3 cm wider. Patients in the sham EA group received shallow acupuncture needle stimulation (without cutaneous penetration of the needle tip, and without stimulation electric current output). All the patients of the 3 groups were given EB (1% Lidocaine, 0.05% Sufentanil and 0.1% Ropivacaine) and patient-controlled epidural analgesia (PCEA) when the orifice of the uterus opened about 3 cm wider. The pain severity was assessed by using Visual Analogue Scale (VAS) at time-points of immediately after EA, 1 h after EA, 2 h after EA, immediately after EB, 1 h after EB, 2 h after EB and full open of the uterus orifice. The contents of serum adrenocorticotrophic hormone (ACTH) and cortisol (COR) were assayed by using ELISA. RESULTS: There was no significant difference in the VAS score at the immediate time of post-EA among the three groups (P>0.05). Compared with the EB group, the VAS scores at all time-points except the immediate time of post-EA were significantly decreased in the EA group (P<0.05). One and 2 h after EB, and after full open of the uterus orifice, the VAS scores in the 3 groups were all evidently decreased (P<0.05), and those of the EA group were significantly lower than those of the sham EA and EB groups (P<0.05). The three groups had a significant increase in the levels of serum ACTH and COR at time-points of 1 and 2 h after EA, immediately after EB, and when the orifice of the uterus was fully opened (P<0.05), presenting a gradual increase of their level during the course of labor. Compared with the EB group, the levels of serum ACTH and COR contents were considerably decreased in the EA group (rather than in the sham EA group) (P<0.05). The dosages of Ropivacaine and Sufentanil, the total pressing times and the effective pressing times of PCEA pump were significantly lower in the EA group than those in the EB and sham EA groups (P<0.05). CONCLUSION: EA plus epidural analgesia, given during the latency period of labor, can effectively alleviate pain, inhibit stress response and reduce the dosage of anesthetics in primiparous parturients throughout the labor process.