McFadden E R, Denison D M, Waller J F, Assoufi B, Peacock A, Sopwith T
J Clin Invest. 1982 Mar;69(3):700-5. doi: 10.1172/jci110498.
In an effect to determine how far inspired air could penetrate into the respiratory tract before being brought to body conditions, we measured the temperature in the airways of the anterior basilar segment of the right lower lobe in five normal subjects while they breathed air at subfreezing and ambient conditions. During quiet breathing, most of the heating of the incoming gas took place in the upper airways as expected. However, as the thermal burden was increased by rapid inspirations, frigid air, and hyperventilation, the temperature of the distal airways progressively fell and the point at which the incoming air reached body conditions moved deep into the periphery of the lung. These findings demonstrate that heat and water transfer is not localized to one region, but rather is a continuous process that begins the moment the air enters the body and involves as much of the respiratory tract as necessary to complete the task.
为了确定吸入空气在达到人体条件之前能深入呼吸道多远，我们在五名正常受试者于低于冰点和环境条件下呼吸空气时，测量了右下叶前基底段气道中的温度。在安静呼吸时，如预期的那样，进入气体的大部分加热发生在上呼吸道。然而，随着快速吸气、冷空气和过度通气增加了热负荷，远端气道的温度逐渐下降，进入空气达到人体条件的点深入到肺的外周。这些发现表明，热和水的传递并非局限于一个区域，而是一个连续的过程，从空气进入身体的那一刻就开始了，并且涉及完成该任务所需的尽可能多的呼吸道部分。
