Pulmonary Circulation Flashcards
What is the typical source of hemoptysis, where does this structure drain, and what is the significance?
bronchial circulation
drains into the left atrium
acts as a shunt because doesn’t get oxygenated
How do you calculate pulmonary vascular resistance (PVR)?
PAP - LAP = CO x PVR
Which has higher resistance, systemic or pulmonary circulation?
systemic
which has high elastance/low compliance, systemic or pulmonary circulation?
systemic circulation
which has a low pressure, systemic or pulmonary circulation?
pulmonary circulation
What are the 2 methods for measuring pulmonary arterial pressure and which one is better?
method 1 = echo for estimation (+/- 10 mmHg)
method 2 = pulmonary artery wedge/occlusion pressure BEST ONE
What are the normal pressures for RA, RV, PA, MAP PA, PCWP, CO, and PVR?
RA = 0-5 mmHg RV = 25/10 mmHg PA = 25/10 mmHg MAP PA = 15-20 PCWP = 5-8 mmHg CO = 5 L/min PVR = 1-2 woods units (WU)
On a swan Ganz cath, which top humps should be even if normal?
right ventricle and pulmonary artery
on a Swan Ganz Cath, which bottom humps should be even if normal?
- Right atrium to right ventricle
- Pulmonary artery to pulmonary artery occlusion/wedge pressure
If the cardiac output increased from 5L/min to 20L/min but the pulmonary pressure only increases 1/2 of expected increase, what are the mechanisms?
2 mechanisms
- high capacitance (more distensible vessels than systemic arteries)
- recruitment of unperfused vessels (west zones of the lung)
True of False: Gravity affects air pressure
False: gravity only affects blood pressure but not air pressure
Where are MAP and MVP highest in the lung?
at the bases due to gravity
Where is the mean alveolar pressure greatest?
it is the same everywhere
Where are West Zone 2 and when does blood flow occur?
West Zone 2 = Apices
Blood flow only occurs during systole and not during diastole because systole makes the Pa >PA but not enough pressure during diastole to make Pa >PA anymore so capillaries close
Where is West Zone 3 and what happens there?
Base of the lungs, blood flow always occurs in this area during systole and diastole
Where is West Zone 1 and what happens there?
West Zone 1 doesn’t exist in healthy individuals
there is no blood flow ever at this area because Pa
What does Zone 2 provide when CO increases?
vascular reserve because the pulmonary pressure is increased so there will not be collapse during diastole
what happens to the zones when a patient is given a bolus of fluid?
Zone 2 becomes Zone 3
what causes cariogenic pulmonary edema?
increased vascular hydrostatic pressure
what causes non-cariogenic pulmonary edema?
increased permeability of vessel and proteins leave the vasculature pulling fluid with it
how is cariogenic pulmonary edema related to pulmonary capillary wedge pressure?
when the pulmonary capillary wedge pressure increases, there is an increase of hydrostatic pressure leading to cardiogenic pulmonary edema
What is the classic CXR finding for pulmonary edema and why does it occur?
Kerley B lines,
occurs because interlobular septae fill with fluid
Which type of pulmonary edema forms faster given the same microvascular pressure?
non-cardiogenic pulmonary edema because there is increased permeability due to damaged vessels
If a patient comes in with respiratory failure and has a capillary wedge pressure of 20 mmHg, how would you treat them?
use diuretic
capillary wedge pressure = LAP which means that there is fluid overload which can be treated through diuresis
If a patient comes in with a crush injury and develops respiratory failure 6 hours later, what is the treatment?
lung protective ventilation
True or False: Diuretics help treat non-cariogenic shock
False, non-cardiogenic shock is not caused by fluid overload from heart failure but rather from leaky vessels within the lung
