Ohya N, Huang J, Fukunaga T, Toga H
Department of Internal Medicine, Kanazawa Medical University, Uchinada, Japan.
Tohoku J Exp Med. 1988 May;155(1):103-4. doi: 10.1620/tjem.155.103.
The mouth pressure curve after abrupt interruption during forced expiratory maneuver was investigated to evaluate the collapsing state of the airway downstream to the choke point. Immediately after the airflow interruption at the mouth by means of the electromagnetic valve, the mouth pressure suddenly increased (1st phase), followed by a slower rise (2nd phase) within about 100 msec until the pressure reaches the alveolar pressure. The pleural and alveolar pressures remained constant during this process. It was evidenced that, from point of view of mean flow, the airflow flowed at a rate of Vmax through the choke point during the second phase. Thus, it is strongly suggested that the choke point remained at the same point during the 2nd phase. From these results, the 2nd phase of the mouth pressure is expected to represent the specific characteristics for the downstream airway.
为评估阻塞点下游气道的塌陷状态，研究了用力呼气动作突然中断后的口腔压力曲线。通过电磁阀在口腔处气流中断后，口腔压力立即突然升高（第一阶段），随后在约100毫秒内缓慢上升（第二阶段），直至压力达到肺泡压力。在此过程中胸膜和肺泡压力保持恒定。有证据表明，从平均流量的角度来看，在第二阶段气流以Vmax的速率通过阻塞点。因此，强烈提示在第二阶段阻塞点保持在同一点。根据这些结果，预计口腔压力的第二阶段代表下游气道的特定特征。
