Initiating the Breath: The Drive to Breathe, Muscle Pump
The initiation of a breath is the consequence of the interaction of a complex set of neural inputs to the respiratory centers of the brain and the mechanical properties of the ventilatory pump. Automatic and volitional elements must be considered, as well as behavioral effects resulting from symptoms and psychological factors. A range of pathological conditions may alter different pieces of the respiratory system resulting in changes in respiratory pattern and, in some cases, gas exchange. This chapter will outline the physiology of the key neuromechanical components of the respiratory system responsible for initiation of the breath and review the tests that may be used to assess the system.
KeywordsDiaphragm muscle Diaphragm motor units Motor unit recruitment Ventilatory control
- Burke RE. Motor units: anatomy, physiology and functional organization. In: Brookhart JM, Mountcastle VB, editors. Handbook of physiology, Sec. 1, Vol. III, Part 1, The nervous system. Bethesda: American Physiological Society; 1981. p. 345–422.Google Scholar
- McCloskey DI, Gandevia S, Potter EK, Colebatch JG. Muscle sense and effort; motor commands and judgments about muscular contractions. In: Desmedt JE, editor. Motor control mechanisms in health and disease. New York: Raven Press; 1983.Google Scholar
- Miller MR, Crapo R, Hankinson J, et al; ATS/ERS Task Force. General considerations for lung function testing. Eur Respir J 2005;26:153–61.Google Scholar
- Sieck GC. Neural control of the inspiratory pump. NIPS. 1991;6:260–4.Google Scholar