par Naeije, Robert 
;Peacock, Andrew
Référence Encyclopedia of Respiratory Medicine, Second Edition, Elsevier, Vol. 3, page (486-505)
Publication Publié, 2021-01
;Peacock, AndrewRéférence Encyclopedia of Respiratory Medicine, Second Edition, Elsevier, Vol. 3, page (486-505)
Publication Publié, 2021-01
Partie d'ouvrage collectif
| Résumé : | The pulmonary circulation is a high-flow/low-pressure circuit. Pulmonary vascular pressure-flow relationships in fully recruited lungs conform to distensible vessel models with a correction for hematocrit. Left atrial pressure is transmitted upstream to pulmonary artery pressure in a less than 1/1 ratio in steady flow conditions, but in a higher than 1/1 ratio in pulsatile flow conditions. The distribution of pulmonary perfusion is mainly determined by gravity, but corrected to some extent by hypoxia-induced vasoconstriction to preserve matching of flow to regional decrease in ventilation. Strenuous exercise and/or hypoxia may be a cause of pulmonary edema or right ventricular failure on high pulmonary vascular pressures. |
