Abstract

Thoracoabdominal movements (TAM) represent two parallel pathways for the distribution of body wall volume displacements. Thoracic and abdominal pathways provide two “degrees of freedom” by which body wall movements accommodate lung volume changes (12). During spontaneous breathing in normal humans, inspiration is the “active phase” of respiration, and expiration is normally passive. Respiratory movements of the thorax and abdominal wall are both driven by the actions of the diaphragm, as well as by muscles intrinsic to each structure. To a useful approximation, abdominal movements reflect directly the movements of the diaphragm in quiet breathing. Thoracic movements may be passive (caused by the action of the diaphragm, using the abdominal contents as a fulcrum to lift the lower rib cage) or active (caused by action of the intercostal and thoracic “accessory” inspiratory and expiratory muscles). During normal quiet breathing, thoracic and abdominal movements are in large part, passive, closely synchronized (in phase), reflecting primarily the action of the diaphragm driving both structures (8). It may be said that TAM during resting breathing are relatively unitary: not only are thoracic and abdominal movements in phase, but their relative amplitudes are nearly constant. This constitutes TAM manifesting only one “degree of freedom,” (despite the potential for utilizing two degrees of freedom).KeywordsRespiratory MuscleSpontaneous BreathingnonREM SleepExpiratory MuscleQuiet BreathingThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.