Pulmonary and Bronchial Circulation
Pulmonary blood flow is the denominator of the ventilation-perfusion ratio, V A/Q, and is of equal importance with breathing in determining the overall efficiency of pulmonary gas exchange (Table 104.1). A major hemodynamic difference between the systemic and pulmonary circulations [4,6] is that the entire cardiac output passes through the lungs — which has only about 1% of the body mass — and it does so with a mean pulmonary arterial-to-left atrial driving pressure that is less than one-tenth that of the systemic circulation. The difference is that in the pulmonary circulation the small muscular arteries and arterioles, both by their enormous number and their low basal smooth muscle tone, contribute much less to total flow resistance than their systemic counterparts.
KeywordsPermeability Hydrolysis Filtration Dopamine Pneumonia
Unable to display preview. Download preview PDF.
- 2.Deffenbach ME, Charan NB, Lakshminarayan S, Butler J (1987) The bronchial circulation: small, but a vital attribute of the lung. Am Rev Respir Dis 135:463–481Google Scholar
- 4.Grover RF, Wagner WW Jr, McMurtry I, Reeves JT (1984) Pulmonary circulation. In: Shepherd JT, Abboud FM (eds) Handbook of physiology: the cardiovascular system. III. American Physiological Society, Bethesda, pp 103–136Google Scholar
- 5.Gunteroth WG, Luchtel DL, Kawabori I (1982) Pulmonary micro-circulation — tubules rather than sheet and post. J Appl physiol 53:510–515Google Scholar
- 6.Harris P, Heath D (1978) The human pulmonary circulation, 2nd edn. Livingston, EdinburghGoogle Scholar
- 9.Staub NC (1984) Pathophysiology of pulmonary edema. In: Staub NC, Taylor AE (eds) Edema. Raven, New YorkGoogle Scholar
- 10.Staub NC (1990) Pathways for lung liquid clearance. In: Brigham KL, Stahlman MT (eds) Respiratory distress syndromes: molecules to man. Vanderbilt, Nashville, pp 33–43Google Scholar