Mechanical arrangement of costal and crural diaphragms in dogs

• DOI: 10.1152/jappl.1984.56.6.1484
• Publication Date: 2017-12-21T13:15:43Z
• Authors: M. Decramer; A. De Troyer; S. Kelly; P. T. Macklem
• Keywords: Diaphragm (acoustics); Supine position

To assess the mechanical arrangement of costal and crural parts diaphragm, we studied changes in diaphragmatic length with piezoelectric crystals 17 supine anesthetized dogs. During control resting inspiration, part usually shortened more earlier than part. After phrenicotomy, always lengthened during whereas or lengthened. These interanimal differences disappeared after opening abdomen; then inspiration. stimulation one part, relaxed nonstimulated However, when compared relationship between transdiaphragmatic pressure (Pdi) obtained passive deflation, lengthening either was small. This difference predicted measured Pdi-length decreased magnitude as lung volume increased above functional residual capacity (FRC) approached. results indicate that 1) even quiet breathing diaphragm dog is not a single entity; 2) at FRC portions behave if they were mechanically arranged partly parallel series; 3) gradually move into pure series increases.