Flashcards in Alveolar destruction & +++ pulmonary artery press. Deck (33):
True or false type two respiratory failure is any cause of inadequate ventilation?
What's diffuses easier across the alveolar membrane: CO2 or O2?
Approximately how many alveoli do you have in your lungs?
200 to 300 million
What four things are the alveolar capillary membrane composed of?
Player of surfactant
type alveolar cell
vascular endothelial cell
How thick is the alveoli – capillary membrane?
2 cells thick
What is the average surface area for diffusion of gases in the lungs?
Why are the lungs ideally suited for gas exchange?
Large surface area and thinness
3 physiological effects of disrupting the a – c membrane?
1. abnormal gas exchange
2 abnormal lung mechanics
3 pulmonary vascular complications
What does Fick's law determine??
Rate of diffusion of the gas
Should there be a limitation in diffusion of oxygen in a normal person at maximum exercise?
Nope. only perfusion limited
When would you get a diffusion limitation of oxygen transfer? 2 situations
at rest if abnormal A-C membrane
during exercise if less severe disease
How much faster does CO2 diffuse out compared to O2?
When is one of the only times he would get a high PaCO2?
low ventilation ie. type 2 reap failure
How is emphysema an exception in the restrictive lung disease category?
It has increased lung compliance not stiffer
What is the pattern of breathing for restrictive lung diseases?
Short and shallow rate
Increased work of breathing needs to overcome the stiffness of what in the lungs?
elastic/reduced compliance of lungs
What is the PaO2 and PaCO2 of someone in respiratory muscle fatigue/failure?
PaO2 is less than 60mmHg
PaCO2 is greater than 50 mmHg
What is a hallmark reduction in someone with stiff lungs?
reduced vital capacity
Compliance of the lungs are affected by two things they are?
Surface tension in alveoli
Over compliant/elastic lungs are what disease?
Pulmonary fibrosis does what to the compliance of the lungs?
For a minute ventilation a person will adopt a pattern of breathing that is what?
Minimizes the work of breathing
how is maximum ventilation affected in restrictive lung diseases?
reduced especially in exercise
What does asbestosis do to lungs?
abnormal increases in fibrosis and diffuse inflammation that destroys A-C membrane
What kind of crackles do you hear with asbestosis?
inspiratory crackles of airways popping open due to collapses
What does the following indicate?
tender pulsatile hapatomegaly
How do you get a tricuspid pan-systolic murmur?
when you have right ventricular dilatation and the cusps don't come together perfectly due to inexperience with higher pressures
Pulmonary hypertension does what to the right atrial and systemic venous pressures??
What is ascites?
accumulation of fluid in the peritoneal cavity causing swelling
What happens when you increase systemic venous pressure to the systemic capillary bed? 3 things:
Three most common causes of increased pulmonary area vascular resistance:
obstruction (emboli, pulm HTN)
obliteration (emphysema, fibrosis)
The three most common causes of pulmonary hypertension?
Increased left atrial pressure (mitral stenosis)
Increased pulmonary blood flow (shunts, HTN)
Increased pulmonary vascular resistance