Jones P L, Rosen M, Mushin W W, Jones E V
Br Med J. 1969 Aug 2;3(5665):259-62. doi: 10.1136/bmj.3.5665.259.
Methoxyflurane (0.35%) in air and nitrous oxide/oxygen (50%/50%) self-administered intermittently in the usual way have been compared as analgesics for labour. There were 25 patients in each group. Objective assessment by an anaesthetist showed that methoxyflurane is the more effective analgesic, and this was supported by the opinion of the multiparae. Nausea and vomiting were significantly less with methoxyflurane. Fifty per cent. nitrous oxide in oxygen given intermittently does not appear to be the best analgesic concentration. Nevertheless, since a considerable variation in sensitivity exists, it would probably be unwise to consider the introduction of higher concentrations for use by unsupervised midwives.This trial confirms the predictions made by us using a method for screening inhalational analgesics, in which methoxyflurane and nitrous oxide were given continuously.
将空气中的甲氧氟烷（0.35%）与氧化亚氮/氧气（50%/50%）按常规方式间歇性自我给药，作为分娩镇痛剂进行了比较。每组有25名患者。麻醉师的客观评估表明，甲氧氟烷是更有效的镇痛剂，经产妇的意见也支持了这一点。甲氧氟烷引起的恶心和呕吐明显较少。间歇性给予50%的氧化亚氮/氧气似乎不是最佳镇痛浓度。然而，由于敏感性存在相当大的差异，考虑让未经监督的助产士使用更高浓度的药物可能不明智。该试验证实了我们使用一种吸入性镇痛剂筛选方法所做的预测，在该方法中，甲氧氟烷和氧化亚氮是持续给药的。
