Clinical Study On Labor Analgesia And Maternal-Infantile Safety Of Electroacupuncture

1 OBJECTIVETo evaluate the clincal effect as well as maternal and infantile safety of electroacupuncture for labor analgesia using a single blind, randomized controlled trial in order to provide safe and effective analgesic method for clinical obstetrics.2 METHODS2.1 Diagnostic CriteriaAccording to "Obstetrics and Gynecology"(6th edition), chief editor:Le Jie, published by People's Medical Publishing House, the diagnostic criteria referred to definitions of "delivery", "term delivery" and "in labor". Inclusive, exclusive, eliminating, as well as dropping off criteria were strictly formulated.2.2 Criteria for Therapeutic Evaluation2.2.1 Clincial criteria for therapeutic evaluationVisual Analogue Scale(VAS) was employed to assess pain easement. And WHO pain grading standard was applied for observers to assess pain of parturients.2.2.2 Criteria for safety evaluationAccording to "Physiology"(6th edition), chief editor:Yao Tai, published by People's Medical Publishing House, the normal blood pressure, heart rate, respiratory rate were referred to in the research. According to "Obstetrics and Gynecology"(6th edition), chief editor:Le Jie, published by People's Medical Publishing House, the Apgar score of neonatus, amniotic fluid, and the amount of vaginal hemorrhage after 2 hours of postpartum were referred to in the research.2.3 Grouping and Treatment PlanOne hundred and four cases of parturients of head delivery were randomly divided into an electroacupuncture group and an epidural analgesic group, with the scale of 1:1,52 cases in each group. Meanwhile another 52 cases without analgesic methods were served for observation on analgesic effect and influnce on maternal and infentile safety.In electroacupuncture group, acupoints as bilateral Hegu(LI 4), Zusanli(ST 36), and Sanyinjiao(SP 6) were picked. After patients got needling sensation, the needls were linked by HANS with frequency 2/100Hz, intensity that parturients could endure. And it lasted until the cervix was fully opened with an alternation of stimulation for 30 mins and an intermission for 15 mins.In epidural analgesic group, PCEA was adopted and applied by anesthetist.Parturients in non-analgesic group got no analgesic treatments.Parturients in three groups were treated by routine obstetric regulations.2.4 Observation Indexes and Time Points2.4.1 Indexes of clinical therapeutic evaluationVAS scores, pain grades of uterine contraction, time of labor stage, dose of oxytocin, labor pattern, content ofβ-endorphin in peripheral blood. 2.4.2 Indexes of safetyBlood pressrue, heart rate, respiratory rate, amniotic fluid, the amount of vaginal hemorrhage after 2 hours of postpartum as well as Apgar score of neonatus.2.4.3 Observation time pointsAnalgesia was used when the cervix was open for 2-4cm, and indexes were observed and recorded at the time point before treatment,0.5h, 1h,2h,3h after the beginning of treatment, and the time point after treatment.2.5 Data Process and Statistical AnalysisEpidata3.1 was used to establish database, and CHISS software was used to analyze the results. Quantitative data in normal distribution was processed by analysis of variance, while in abnormal distrbution, it was analyzed by Kruskal Wallis test. And enumeration data was processed by chi-square test.3 RESULTS3.1 VAS3.1.1 Comparison among groupsVAS scores at 0.5h, 1h,2h,3h time points after beginning of treatment and the time point after treatment had extremely significant differences compared to that of before treatment (P<0.01)VAS scores in epidural analgesia group at each time point after beginning of treatment were all lower than those in electroacupuncture group and non-analgesic group, with significant differences (all P<0.01). VAS scores in electroacupuncture group at each time point after beginning of treatment were all lower than those in non-analgesia group, with significant differences (all P<0.01)3.1.2 Comparisons within group3.1.2.1 Electroacupuncture groupVAS scores in electroacupuncture group at 0.5h, 1h,2h,3h time points after beginning of treatment and the time point after treatment had extremely significant differences compared to that of before treatment (P<0.01);VAS scores at time points after beginning of treatment were all lower than that of before treatment;VAS score at 1h time point after beginning of treatment was lower than that at 0.5h, with a significant difference (P<0.05); VAS score at 3h time point after beginning of treatment was lower than that at 0.5h, with a significant difference (P< 0.05)3.1.2.2 Epidural analgesic groupVAS scores in epidural analgesic group at 0.5h, 1h,2h,3h time points after beginning of treatment and the time point after treatment were all lower than that of before treatment, with extremely significant differences (P<0.01);VAS score at 1h time point after beginning of treatment was lower than that at 0.5h time point, with a significant difference (P<0.05); VAS score at 2h time point after beginning of treatment was lower than that at 0.5h time point, with a significant difference (P<0.05);VAS score at the time point after treatment was higher than those at 1h,2h,3h time points after beginning of treatment, with significant differences (P<0.05)3.1.2.3 Non-analgesic groupVAS scores in non-analgesic group at 0.5h, 1h,2h,3h time points after beginning of treatment and the time point after treatment had extremely significant differences compared to that of before treatment (all P<0.01) and the scores increased in sequence.There were no significant differences between VAS scores at 2h and 3h time points after beginning of treatment,2h after beginning of treatment and the time point after treatment,3h after beginning of treatment and the time point after treatment (all P>0.05). However, there were significant differences of VAS scores among other time points (all P< 0.05)3.2 Pain grades of laborThere were no significant differences among groups before treatment (all P> 0.05), and after the beginning of treatment, there were significant differences after treatment compared to those of before treatment (all P< 0.05)At all the time points after beginning of treatment, pain grades distributed in general as:in electroacupuncture group, most parturients had the second grade of pain, while in epidural analgesic group, the first grade was for most, and in non-analgesic group, the third grade was for most. It illustrated that the analgesic effect got according to pain grades of uterine contraction in desending order was: electroacupuncture group, epidural analgesic group, and non-analgesic group.3.3 Time of stages of laborThe time of the first and second stages of labor in electroacupuncture group was the shortest, the time in epidural analgesic group was the longest, while in non-analgesic group the time cost was between them with significant differences(both P<0.05). The time of the third stage of labor in epidural analgesic group was the longest, followed by that of electroacupuncture group, and then that of non-analgesic group, but without significant differences (both P>0.05)3.4 Content ofβ-endorphin in peripheral bloodThere were no significant differences ofβ-endorphin content in peripheral blood before observation among three groups (all P>0.05), but at the time point of 2h after beginning of treatment, there were significant differences(all P<0.05).After treatment for 2h, content ofβ-endorphin both raised in electroacupuncture and epidural analgesic group, and it was higher in epidural analgesic group without a significant difference (P>0.05). Content ofβ-endorphin was higher in electroacupuncture and epidural analgesic group than that in non-analgesic group(both P<0.05).3.5 Index of safetyBlood pressure before treatment had no significant differences among three groups (all P>0.05);Parturients in three groups at every time point had abnormal heart rate but without significant differences (all P>0.05);At time points of 1h and 2h after treatment, the respiratory rates of parturients had significant differences among three groups(all P<0.05) and that indicated at time points of 1h and 2h after beginning of treatment, parturients in electroacupuncture group had quicker respiratory rate, but still in normal physiologic range.The amount of vaginal hemorrhage after labor among three groups had no significant differences (all P>0.05);Apgar scores of neonatus among three groups had no significant differences among three groups (all P>0.05)4 CONCLUSIONS(1)Electroacupuncture analgesia, easy and simple to operate, is safe and effective to be applied in the first stage of labor, and thus a favorable non-drug analgesic therapy.(2)Electroacupuncture analgesia applied to spontaneous labor can shorten the time of first and second stages of labor. Electroacupuncture possess effect on induction of labor.(3)Electroacupuncture analgesia has no influences on intervention of oxytocin,delivery patterns, the amount of vaginal hemorrhage after 2h of postpartum, as well as Apgar score of neonatus.The result shows electroacupuncture analgesia posses safty in the first stage of labor.(4)Electroacupuncture can raise content ofβ-endorphin in peripheral blood of parturients and thus increases pain threshold to relieve it.