Fuller S D, Robinson N E
Department of Physiology, Michigan State University, East Lansing 48824-1101.
Respir Physiol. 1988 Dec;74(3):253-63. doi: 10.1016/0034-5687(88)90034-5.
Collateral airway resistance was measured during inflation of an excised lung lobe or a segment within the lobe. Gas blown into the outer lumen of a double lumen catheter (Vcoll) inflated the segment and exited via collateral airways. Pressure at the catheter tip (Pct) was measured through the inner lumen of the catheter, and transpulmonary pressure (Pao) was measured at the lobar bronchus. A pleural capsule measured pressure in the segmental subpleural alveoli (Ps). The segment was inflated with helium (He), air, or sulfurhexafluoride; the lobe was ventilated with air. Collateral airway resistance [Rcoll = (Pct-Pao)/Vcoll], intrasegmental airway resistance [Rs = (Pct-Ps)/Vcoll], and resistance of airways passing through the segment-lobar interface [Ri = (Ps-Pao)/Vcoll] were calculated. Rcoll, Rs, and Ri were decreased by lobar inflation and increased by segment inflation. The latter increase was due to nonlaminar flow in intrasegmental airways. The major resistance was Ri when Vcoll was laminar or transitional. Moody plots suggested that lobar inflation caused intrasegmental airway dilation whereas segment inflation did not affect segment airway geometry.
在离体肺叶或肺叶内的一个肺段充气过程中测量侧支气道阻力。吹入双腔导管外腔的气体（Vcoll）使该肺段充气，并通过侧支气道排出。通过导管内腔测量导管尖端的压力（Pct），并在叶支气管处测量跨肺压（Pao）。胸膜囊测量肺段胸膜下肺泡的压力（Ps）。用氦气（He）、空气或六氟化硫使肺段充气；用空气使肺叶通气。计算侧支气道阻力[Rcoll = (Pct - Pao)/Vcoll]、肺段内气道阻力[Rs = (Pct - Ps)/Vcoll]以及通过肺段 - 肺叶界面的气道阻力[Ri = (Ps - Pao)/Vcoll]。肺叶充气使Rcoll、Rs和Ri降低，而肺段充气使其升高。后者的升高是由于肺段内气道的非层流。当Vcoll为层流或过渡流时，主要阻力是Ri。穆迪图表明肺叶充气导致肺段内气道扩张，而肺段充气不影响肺段气道几何形状。
