Lichtenthal P, Philip J, Sloss L J, Gabel R, Lesch M
Chest. 1977 Sep;72(3):316-22. doi: 10.1378/chest.72.3.316.
Nitrous oxide (concentrations of 30 to 50%) was administered to 22 healthy volunteer subjects via nasal prongs, rebreathing mask, and an airlines mask to assess the efficiency of systems of delivery and the hemodynamic effects. The end-expired concentration of nitrous oxide, expressed as a percentage of the inspired concentration of nitrous oxide, was 19% for nasal prongs, 34% for the rebreathing mask, and 95% for the airlines mask (most accurate delivery). The pulse rate fell from a mean of 79+/-3 beats per minute to 67+/-2 with nasal prongs, to 64+/-2 with the rebreathing mask, and to 64+/-2 with the airlines mask. Both systolic and diastolic pressures fell from means of 122+/-4 and 74+/-2 mm Hg, respectively, to 98+/-3 mm Hg and 64+/-2 mm Hg, respectively, with the airlines apparatus. The fall in systolic blood pressure (slope, -0.79) exceeded that in the diastolic (slope, -0.35). In additional eight normal subjects, administration of 30% nitrous oxide via airlines mask produced identical changes in blood pressure and pulse rate, but there was no effect from 30 minutes of administration of 30% nitrous oxide on the end-systolic volume index, cardiac index, ejection fraction, normalized wall velocity determined echocardiographically, ejection time, or the ratio of preejection period to ejection time.
通过鼻管、再呼吸面罩和航空面罩，向22名健康志愿者受试者给予一氧化二氮（浓度为30%至50%），以评估给药系统的效率和血流动力学效应。以一氧化二氮吸入浓度的百分比表示的呼气末一氧化二氮浓度，鼻管给药时为19%，再呼吸面罩给药时为34%，航空面罩给药时为95%（给药最准确）。使用鼻管给药时，脉搏率从平均每分钟79±3次降至67±2次，使用再呼吸面罩给药时降至64±2次，使用航空面罩给药时降至64±2次。使用航空设备时，收缩压和舒张压分别从平均122±4毫米汞柱和74±2毫米汞柱降至98±3毫米汞柱和64±2毫米汞柱。收缩压的下降幅度（斜率为-0.79）超过舒张压（斜率为-0.35）。在另外8名正常受试者中，通过航空面罩给予30%一氧化二氮会使血压和脉搏率发生相同变化，但给予30%一氧化二氮30分钟对收缩末期容积指数、心脏指数、射血分数、经超声心动图测定的归一化壁速度、射血时间或射血前期与射血时间之比没有影响。
