lesson 6- Pulmonary Ventilation and Circulation Flashcards
Hypoventilation
Reduced alveolar minute ventilation
hyperventilation
Increased alveolar minute ventilation
what is dead space
The volume of the airways that are ventilated but no gas exchange occurs
types of Dead space
Anatomical dead space
Alveolar dead space
Anatomical Dead Space
Conducting zone of the respiratory system without alveoli, ventilated but no gas exchange
What is the Alveolar dead space
Non-perfused but ventilated alveolus
Perfused Alveolus
An alveolus with pulmonary capillaries with blood flowing through it
How do you approximate the volume of anatomical dead space in humans
it is approximately 2ml per kg after 6 years
What factors affect Anatomical Dead space
Weight
Age
Posture
Position of jaw and neck
How does the position of the jaw and neck affect Anatomical Dead Space
It increases the anatomical dead space but reduces airway resistance
What is the Physiological Dead space
Both Anatomical And Alveolar dead space
What is the formula for the alveolar minute ventilation
(Tidal Volume-dead space) x respiratory rate
how does the pulmonary minute blood flow relate to the alveolar minute ventilation
They are approximately equal and well matched
What is the diff. b/w pressure in Pulmonary circulation and systemic circulation
Pressure in pulmonary circulation is far lower than the pressure in systemic circulation
What is the diff. b/w resistance in Pulmonary circulation and systemic circulation
Resistance in the systemic circulation is far greater than resistance in the pulmonary circulation
How does Resistance relate to Pressure
Resistance and pressure are directly proportional
What equation can you use to relate Resistance and pressure
V = IR
Where V is Pressure
I is flow
What is the diff. b/w the blood flow in Pulmonary circulation and systemic circulation
The blood flow in both Pulmonary and systemic circulations is approximately the same
What is the diff. b/w capacity in Pulmonary circulation and systemic circulation
Pulmonary circulation has a higher capacity than Systemic circulation
How much blood is stored in the lungs
About 12% of the total blood volume
how does the systemic circulation react to hypoxia
there is vasodilation to allow more oxygen-rich blood to reach the tissue
how does the pulmonary circulation react to hypoxia
there is vasoconstriction to divert deoxygenated blood from the hypoxic alveolus, for more efficient oxygenation of blood
What factors lead to increasing pulmonary vasorestriction(causing pulmonary vasoconstriction)
Decreased levels of alveolar partial pressure of oxygen
Increased alveolar partial pressure of CO2
Acidosis
