Clinical study on labor analgesia with inhalation of nitrous oxide in active stage of labor

Objective:To investigate the efficiency of the inhalation of nitrous oxide premixed with oxygen(50%:50%) for labor analgesia and its effects on mother and fetus. Methods:320 primiparae were randomly divided into the observation group and control group,with 160 cases in each group. The observation group was treated with the inhalation of nitrous oxide with oxygen,the control group only with oxygen. The degree of labor pains,delivery process,ways of delivery,Apgars score,postpartum hemorrhage and the blood gas analyses of maternal radius artery and fetal umbilical artery in all cases were observed respectively,and compared with each other. Results:The efficiency of analgesia in active stage of labor in the observation group was significantly superior to that in the control group, with a significant difference(P0.001), but there were no significant differences in the time of labor, postpartum hemorrhage, Apgars score, blood gas analysis between two groups (P0.05). Conclusion:The inhalation of nitrous oxide premixed with oxygen for labor analgesia benefits pregnant women,without side effects on both mother and fetus,which is a safe,simple and effective method.