Mechanism's _ symptom that the lung artery has illness coming on under high pressure

Mechanism's _ symptom that the lung artery has illness coming on under high pressure
1.The onset mechanism lung circulates and includes right ventricle, lung artery capillary and pulmonary vein, its main function is to carry on blood flow dynamics of air exchange and have four following characteristics: The pressure is low: The intersection of lung and artery pressure 19/16mmHg at the normal quiet interest, press for (12 2) on average MmHg, systolic pressure less than 25mmHg is 1/6 of aorta, lung blood vessel pour into, pigeonhole low the intersection of lung and artery and left the intersection of heart and room pressure difference only 6mmHg too, it is l/7- 1/10 of the normal aorta pressure; Resistance is small: Because lung blood vessel short and tube wall great to expand degree so blood flow the intersection of resistance and little normal the intersection of people and the intersection of lung and blood vessel resistance the intersection of systemic circulation and 1/5 - l/10 of resistance; The velocity of flow is fast: Dirty all blood that accepts the heart fights out of lung but its procedure is far shorter than systemic circulation, so the velocity of flow is fast; The capacity is large: Bed area of blood vessel of the lung can hold 900mL blood, accounts for all oligemic 9%.
Lung arterial pressure =Blood vessel resistance * of lung Lung blood flow volume + Pressure of atrium sinistrum
So lung the intersection of artery and the intersection of pressure and level decide by the intersection of lung and the intersection of blood vessel and resistance, the intersection of lung and blood flow volume and left the intersection of room and the intersection of pressure and the intersection of lung and artery, include 3 requirements and blood vessel of structure roughly, namely the elasticity type artery of external diameter> 1000 m lies between skin type artery and external diameter can make the blood vessel resistance of lung increase.
(3)High pressure of pulmonary vein (the lung artery high pressure of sex behind capillary) : Because lung circulate characteristic determine lung move - press difference to be very light among the vein, 2- 10mmHg therefore some disease make the intersection of lung and venous pressure lung arterial pressure rise while being corresponding even raise, only, common the left room function is not complete that can also happen at bicuspid valve pathological change, left room mucus tumour of hearts of room three for a long time, the complying with low lung when as the venous pressure of lung is raised of left room is arteriolar
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