Pulmonary Circulation Flashcards
What can be described as low pressure/high flow system
pulmonary artery and its branches
What % of blood volume is found in the lungs?
9% (450 mL)
what can be described as high pressure/low flow system?
the bronchial arteries ( supplying the lung tissue itself)
What is the pressure gradient in the pulmonary system?
The difference btw the mean pulmonary arterial pressure and the diastolic pressure in the left atrium …. the gradient is approximetly 7mm Hg
What is the mean normal pressure in the left atrium?
2 mm Hg
In order to increase blood flow to the lungs during excersise…
the number of open capillaries increases as much as 3X normal, the capillaries become more distended, and there is an increase in pulmonary arterial pressure.
What are the zone pressures for the lung at rest?
The apices of the lungs has a zone 2 pattern of pulmonary blood flow, while the remainder of the lungs show a zone 3 pattern.
Why do blood in the systemic arteries contain less oxygen per deciliter than blood that has equilibrated with the alveolar air?
The physiological shunt.
What does a reduction of blood flow to a portion of the lung do?
Lowers alveolar pCO2 and results in a constriction of the bronchi supplying that portion of the lung.
