9. CP Pulmonary Blood Flow Flashcards
What are the systolic and diastolic pressures for the atria?
15/4 (right and left)
What are the systolic and diastolic pressures for the right ventricle?
25/0
What are the systolic and diastolic pressures for the left ventricle?
120/0
What are the systolic and diastolic pressures for the lungs?
25/15
What are the systolic and diastolic pressures for the aorta?
120/80
What is the function of the extra-alveolar capillaries?
They take oxygenated blood from the left ventricle and supply the tissue of the lungs and respiratory tract itself.
What is meant by the term “venous admixture” in reference to the extra-alveolar capillaries?
Blood that is used by the respiratory tissues is returned via the pulmonary veins, which is carrying freshly oxygenated blood. As such the pulmonary veins return blood that is both freshly oxygenated, and slightly used.
Why might low or very high lung volumes increase pulmonary vascular resistance?
The stretch of the tissue compresses the capillaries.
What is a normal blood flow per minute?
5L / min
What four molecules are chemical modulators of pulmonary blood flow?
NO
Thromboxane A2
Endothelin 1
Oxygen
What is the main player in chemical modulation of pulmonary blood flow?
What is it produced by?
NO (Nitric Oxide)
Produced by the endothelium
What is the role of oxygen in regulating pulmonary blood flow?
Oxygen relaxes (opens) blood vessels.
Therefore areas of low O2 in the lungs have a higher vascular resistance in order to shunt blood away from that area.
Under what conditions do thromboxane A2 and endothelin 1 play a role in pulmonary blood flow?
Pathological conditions
They are both vasoconstrictors
What are the “starling forces?”
Hydrostatic pressure (negative in this case)
Oncotic pressure
What chemicals are produced by immune activation in the lungs?
Leukotrienes
Prostaglandins / Thromboxane A2
