Chowanetz W, Schott J, Jany B
Dtsch Med Wochenschr. 1987 May 8;112(19):752-7. doi: 10.1055/s-2008-1068133.
27 subjects with healthy lungs received during conscious mouth breathing of room air simultaneously also nasally applied O2. The mean O2 concentration of the expiratory air at the mouth was a measure for the effective inspiratory oxygen concentration. Application through a nasal mask at 4 l/min O2 flow proved only slightly superior to the airtight nose frame (25.2 vs 23.6 per cent by volume O2), whereas the highest concentration was achieved by mask and reservoir (35.3 vol.%; 2P less than 0.001). The five habitual mouth breathers of the subject group did not show any O2 uptake through the nose in any of the experiments, the mean nasal share of the inspiration being calculated at 2.5% against 25% for the other subjects (2P less than 0.001). The interindividual differences proved independent of nose resistance and are ascribed to changing active positioning of the soft palate. This mechanism must be taken into consideration when assessing the arterial blood gases in oronasal respiration.
27名肺部健康的受试者在清醒状态下经口呼吸室内空气的同时，也经鼻给予氧气。口腔呼出气体的平均氧气浓度作为有效吸入氧气浓度的指标。通过鼻罩以4升/分钟的氧气流量给药仅略优于气密鼻架（氧气体积百分比分别为25.2%和23.6%），而通过面罩和储氧袋可达到最高浓度（35.3体积%；P<0.001）。受试者组中的5名习惯性口呼吸者在任何实验中均未显示经鼻摄取氧气，其吸气的平均经鼻比例计算为2.5%，而其他受试者为25%（P<0.001）。个体差异被证明与鼻阻力无关，归因于软腭主动位置的变化。在评估口鼻呼吸时的动脉血气时，必须考虑这一机制。
