Distribution of airway resistance with developing pulmonary edema in dogs

developing pulmonary edema in dogs. J. Appl. Physiol. 32(l) : 20-24. 1972.-Lower airways resistance was partitioned and lung morphology studied in dogs under controlled vascular conditions. We found that as left atria1 pressure (Pla) was increased, periph-eral airways resistance (Rp) showed a gradual increase which was reversible if Pla was not raised above 15 mm Hg. However, above Pla 15 mm Hg Rp rose more steeply and was no longer reversible. The changes in central airways resistance (Rc) were less consistent and usually consisted of an increase in Rc between Pla = 0 and 15 and then a decrease to the control values as Pla was further increased. We conclude that raising left atria1 pressure affects the distribution of airways resistance with the major effect on the peripheral airways. The initial increase in Rp between Pla = 0 and 15 is most likely due to competition for space between arteries and small airways in the bronchovascular sheath, whereas th