Topographical distribution of inspired gas in excised lobes of dogs.

Abstract

Regional distribution of gas was studied in excised lobes of dogs by scanning the lobes after single inflations with radio-active xenon started from various preinspiratory volumes. The distribution of gas was substantially uniform throughout each lobe, but small differences were found between upper and lower lobes. It is concluded that the uneven ventilation distribution in the intact dog is caused not only by regional differences in pleural pressure but also by differences in elastic properties between upper and lower lobes. The effect of the latter factor, although small, is not negligible.