High Risk Pregnancy Labor and Delivery Unit, Enrique C. Sotomayor Obstetrics and Gynecology Hospital, Pedro Pablo Gómez s/n y 6 de Marzo, Guayaquil, Ecuador.
Arch Gynecol Obstet. 2012 Sep;286(3):627-31. doi: 10.1007/s00404-012-2359-6. Epub 2012 May 9.
To analyze the benefits of an inhaled analgesia procedure over intrapartum pain and the degree of satisfaction of using this method.
This was a pilot study carried out at a low-income hospital setting in which women with singleton pregnancies, cephalic presentation and active phase of labor were requested to inhale ad libitum a 50-50 % mixture of nitrous oxide and oxygen (N(2)O-O(2)) (Oxicalm(®), Indura S.A-Indura Ecuador) using a face mask with an auto-demand valve. Effect over labor pain and dynamics and side effects were recorded.
A total of 126 gravids participated with a mean age of 21.6 ± 6.7 years, 50.8 % of which were adolescents. As assessed by the Visual Analog Scale 1 h after initiating the procedure pain significantly decreased 56.2 % on average (8.9-4.9 points, p = 0.001), while increasing cervical dilation and effacement by 28.4 and 21.7 %, respectively. Overall vaginal delivery was achieved in 96.9 % of cases, with an average procedure initiation to delivery time interval of 2 ± 1 h and mixture consumption of 0.93 kg. Vaginal delivery rates were 36.5, 78.6 and 89.7 % for the first, second and third hour, respectively. During that time maternal hemodynamic parameters remained unaltered. Mean duration of the second stage of delivery was 6.2 min. Obstetrical and neonatal outcome was otherwise favorable. Main adverse effect of using the mixture was dizziness (43.7 %) referred by gravids as mild and tolerable. A 96 % of users answered that they would recommend the method and graded it in 92.9 % as good/excellent.
Inhaled intrapartum analgesia using a N(2)O-O(2) 50-50 % mixture provided rapid pain alleviation. It is an appealing, effective and safe method for the management of pain during labor, most useful at institutions with infrastructure and personnel limitations.
分析分娩镇痛吸入程序相对于产时疼痛的益处，以及使用该方法的满意度程度。
这是在一家低收入医院进行的试点研究，要求单胎妊娠、头位、活跃期的孕妇使用带有自动需求阀的面罩随意吸入 50-50%的氧化亚氮和氧气（N(2)O-O(2)）（Oxicalm(®)，Indura S.A-Indura Ecuador）混合物。记录对分娩疼痛的影响以及产程动力学和副作用。
共有 126 名孕妇参与，平均年龄为 21.6±6.7 岁，其中 50.8%为青少年。通过视觉模拟评分法评估，在开始该程序 1 小时后，疼痛平均显著减轻 56.2%（8.9-4.9 分，p=0.001），同时宫颈扩张和消退分别增加 28.4%和 21.7%。总体阴道分娩率为 96.9%，平均启动程序到分娩的时间间隔为 2±1 小时，混合物消耗量为 0.93 公斤。在第一、第二和第三小时，阴道分娩率分别为 36.5%、78.6%和 89.7%。在此期间，产妇的血液动力学参数保持不变。第二产程的平均持续时间为 6.2 分钟。产科和新生儿结局均良好。使用该混合物的主要不良反应是头晕（43.7%），孕妇认为头晕轻度且可耐受。96%的使用者表示会推荐该方法，并将其评分 92.9%为良好/优秀。
吸入分娩镇痛使用 50-50%的 N(2)O-O(2)混合物可迅速缓解疼痛。对于管理分娩疼痛，它是一种吸引人、有效且安全的方法，在基础设施和人员有限的机构中最有用。
