Whitelaw W A, Derenne J P, Milic-Emili J
Respir Physiol. 1975 Mar;23(2):181-99. doi: 10.1016/0034-5687(75)90059-6.
The output of the "respiratory centers" has been estimated by measuring ventilation, inspiratory muscle power, EMG of the diaphragm, and by various other means, each of which has serious disadvantages. The static pressure generated by the inspiratory muscles at FRC against an obstructed airway is here suggested as a useful alternative. Ten conscious, normal, sitting human subjects were subjected to CO2 rebreathing (Read, 1967) and their airways were occluded at end-expiration at intervals without the subjects being aware in advance. The inspiratory pressure waves so generated were found to be distorted by conscious or unconscious responses to the occlusion which had a minimum latency of 0.15 sec. The pressure generated at 0.1 sec after the onset of inspiration (P0.1) was nevertheless easy to measure and was reproducible in each subject. The CO2 response obtained by plotting P0.1 against PCO2, was curvilinear, the P0.1 increasing more rapidly at high PCO2. The P0.1 is independent of pulmonary mechanics. Since it measures the rate of rise of inspiratory activity and not the peak activity it is also independent of mechanisms that alter the respiratory pattern by affecting inspiratory duration, in particular the vagal volume-related inspiratory-inhibitory reflex. It is concluded that measurements of P0.1 represent a useful index of the output of the respiratory centers.
通过测量通气量、吸气肌力量、膈肌肌电图以及其他各种方法，对“呼吸中枢”的输出进行了评估，而每种方法都存在严重缺陷。本文建议，用吸气肌在功能残气量（FRC）时对抗阻塞气道所产生的静压作为一种有效的替代方法。让10名清醒、正常、坐着的人体受试者进行二氧化碳再呼吸试验（Read，1967），并在呼气末不定期阻塞他们的气道，且不让受试者事先知晓。结果发现，如此产生的吸气压力波会因对阻塞的有意识或无意识反应而发生畸变，这种反应的最短潜伏期为0.15秒。然而，吸气开始后0.1秒时产生的压力（P0.1）很容易测量，并且在每个受试者身上都具有可重复性。通过将P0.1与二氧化碳分压（PCO2）作图得到的二氧化碳反应呈曲线关系，在高PCO2时P0.1增加得更快。P0.1与肺力学无关。由于它测量的是吸气活动的上升速率而非峰值活动，所以它也不受通过影响吸气持续时间来改变呼吸模式的机制的影响，特别是迷走神经容量相关的吸气抑制反射。得出的结论是，P0.1的测量值是呼吸中枢输出的一个有用指标。
