Johnson L P, Parkin J L, Stevens M H, Otto W C, McCandless G A
Arch Otolaryngol. 1980 Feb;106(2):100-2. doi: 10.1001/archotol.1980.00790260032010.
An investigation was made of the incidence of "negative myringotomy" or the absence of middle ear effusion when preoperative impedance testing and examination predicted such fluid. The effect of general anesthesia on the clearance of middle ear fluid was studied by comparing preanesthesia and postanesthesia tympanograms with the findings at myringotomy. The effect of nitrous oxide and positive pressure ventilation without nitrous oxide to increase middle ear pressure are mechanisms that could clear low viscosity fluid from the middle ear.
针对“鼓膜切开术阴性”（即术前阻抗测试和检查预测有中耳积液，但术中未发现积液）的发生率展开了一项调查。通过比较麻醉前和麻醉后的鼓室图以及鼓膜切开术时的发现，研究了全身麻醉对中耳积液清除的影响。氧化亚氮以及无氧化亚氮的正压通气增加中耳压力的作用机制，可能是清除中耳低粘度液体的方式。
