Ostfeld E, Crispin M, Blonder J, Szeinberg A
Ann Otol Rhinol Laryngol. 1980 Mar-Apr;89(2 Pt 1):165-7. doi: 10.1177/000348948008900214.
The middle ear gas composition during 180 minutes ventilation with nitrous oxide-oxygen mixture was determined in 12 mongrel dogs. The mean relative concentration of N2O in the middle ear (ME) rose to 12,26.4 and 29.3% after 60, 120 and 180 minutes respectively. During this period, the relative concentration of N2 dropped from a mean of 83.2% in the air-ventilated dogs to 54.8%, without an essential change in the concentrations of O2 or CO2. The elimination of N2O from the ME during 30 minutes of postanesthetic ventilation with O2 was incomplete, an average of 11.4% N2O remaining in the ME. At the same time, the mean relative concentration of O2 reached 19%, higher than the O2 relative concentration normally present in the ME. The results indicate that gas diffusion may occur across the ME mucosa for N2O as well as for O2, producing selective changes in the middle ear gas composition.
在12只杂种犬中测定了使用氧化亚氮 - 氧气混合气体通气180分钟期间的中耳气体成分。中耳（ME）中氧化亚氮的平均相对浓度在60、120和180分钟后分别升至12、26.4和29.3%。在此期间，氮气的相对浓度从通气空气的犬只中的平均83.2%降至54.8%，而氧气或二氧化碳的浓度没有实质性变化。在麻醉后用氧气通气30分钟期间，中耳中氧化亚氮的消除不完全，平均有11.4%的氧化亚氮残留在中耳中。同时，氧气的平均相对浓度达到19%，高于中耳中正常存在的氧气相对浓度。结果表明，氧化亚氮和氧气都可能通过中耳黏膜发生气体扩散，从而使中耳气体成分产生选择性变化。
