Suwannachat Bunpode, Lumbiganon Pisake, Laopaiboon Malinee
Department of Obstetrics and Gynaecology, Kalasin Hospital, Amphur Muang, Thailand.
Cochrane Database Syst Rev. 2012 Aug 15;2012(8):CD006636. doi: 10.1002/14651858.CD006636.pub3.
Vacuum extraction is a common technique of assisted vaginal delivery. Traditionally, it has been recommended that the pressure is increased slowly in a stepwise procedure; some have advocated rapid increases in pressure.
To assess the efficacy and safety of rapid versus stepwise negative pressure application for assisted vaginal delivery by vacuum extraction.
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (4 April 2012).
Randomized controlled trials and quasi-randomized controlled trials of rapid (within two minutes) versus stepwise (as defined by trialists) increases in negative pressure application for vacuum extraction assisted vaginal delivery.
Two review authors independently assessed trials for inclusion and trial quality. The same two review authors extracted data. We entered data into Review Manager software and checked for accuracy. Data extraction and 'Risk of bias' assessment of the contact person's own study were also carried out by three independent assessors who were not involved in the new study.
We included two trials involving 754 participants.One new trial of 660 participants showed the same success rate of vacuum procedure of 98.2% by both methods (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.98 to 1.02).The two included trials showed significant reductions in the time between applying the vacuum cup and delivery, (one trial (74 women): mean difference (MD) -6.10 minutes, 95% CI -8.83 to -3.37 and the other trial (660 women): with median difference -4.4 minutes, 95% CI -4.8 to -4.0). The two included trials showed no significant difference in detachment rate (RR 0.85, 95% CI 0.38 to 1.86, 2 studies, 754 women), no significant difference in Apgar score below seven at one minute (RR 1.04, 95% CI 0.51 to 2.09) and five minutes (RR 1.00, 95% CI 0.29 to 3.42), no significant differences in scalp abrasions or lacerations, cephalhematoma, subgaleal hemorrhage and hyperbilirubinemia. There were no significant differences between the two methods in all secondary outcomes.
AUTHORS' CONCLUSIONS: The rapid negative pressure application for vacuum assisted vaginal birth reduces duration of the procedure whilst there is no evidence of differences in maternal and neonatal outcomes. Rapid method of negative application should be recommended for vacuum extraction assisted vaginal delivery.
真空吸引术是一种常见的阴道助产技术。传统上，建议在逐步操作过程中缓慢增加压力；也有人主张快速增加压力。
评估在真空吸引术辅助阴道分娩中，快速与逐步施加负压的有效性和安全性。
我们检索了Cochrane妊娠与分娩组试验注册库（2012年4月4日）。
关于真空吸引术辅助阴道分娩中，快速（两分钟内）与逐步（由试验者定义）增加负压的随机对照试验和半随机对照试验。
两位综述作者独立评估试验是否纳入及试验质量。同样由这两位综述作者提取数据。我们将数据录入Review Manager软件并检查准确性。三位未参与新研究的独立评估者还对联系人自己的研究进行了数据提取和“偏倚风险”评估。
我们纳入了两项试验，涉及754名参与者。一项有660名参与者的新试验表明，两种方法的真空操作成功率均为98.2%（风险比（RR）1.00，95%置信区间（CI）0.98至1.02）。纳入的两项试验显示，放置真空杯至分娩的时间显著缩短（一项试验（74名女性）：平均差（MD）-6.10分钟，95%CI -8.83至-3.37；另一项试验（660名女性）：中位数差-4.4分钟，95%CI -4.8至-4.0）。纳入的两项试验在脱落率方面无显著差异（RR 0.85，95%CI 0.38至1.86，2项研究，754名女性），在1分钟时Apgar评分低于7分方面无显著差异（RR 1.04，95%CI 0.51至2.09），在5分钟时也无显著差异（RR 1.00，95%CI 0.29至3.42），在头皮擦伤或撕裂伤、头颅血肿、帽状腱膜下出血和高胆红素血症方面无显著差异。两种方法在所有次要结局方面均无显著差异。
在真空辅助阴道分娩中快速施加负压可缩短操作时间，同时没有证据表明母婴结局存在差异。对于真空吸引术辅助阴道分娩，应推荐快速施加负压的方法。
