Pulmonary Edema

Pulmonary Edema





It is less confusing to think of the colloid osmotic pressure as a positive number with a minimum value of zero (NO PROTEIN).





When the rate of fluid filtration from the capillary 
into the interstitium is the rate of lymphatic removal and evaporation - no net fluid accumulation.


• However, when the rate of fluid filtration from the 
capillary into the interstitium is > the rate of lymphatic removal and evaporation - there is net 


fluid accumulation PULMONARY EDEMA.



Cardiogenic Pulmonary Edema



In a normal lung, the driving force for fluid filtration is 
~1 mmHg

• If in CHF the pulmonary capillary pressure increases 
to ~25 mmHg

• Assuming that at least initially Pi ~ 8 mmHg, plasma 
protein osmotic pressure is ~28 mmHg, interstitial 

fluid protein osmotic pressure is ~14 mmHg, and 
remains 0.98

• Then [(25 8) 0.98(28 14)] = ~ 19 mmHg






Treatment for pulmonary edema


Decrease Preload: diuretics, sit patient up in bed, n
itrates, morphine, dialysis.
Improve Cardiac Performance: Nitrates, Inotropes, 
Digoxin.
Decrease Afterload: ACE inhibitors, nitroprusside
Increase Pi: Continuous positive airway pressure, 
mechanical ventilation
Decreasing LpA, or osmotic pressure has not been 
attempted.
Non-cardiogenic Pulmonary Edema

If there is endothelial damage Lp
increases and Jv increases





Capillary endothelium loses barrier function
– Does not require change in hemodynamics
– Forces that oppose Pc decrease
– LpA increases
– leaky capillaries and increased fluid filtration!

Treatment of non-cardiogenic pulmonary edema


Treatment / Removal of offending source (infection , aspiration , inhalation)
• Mechanical Ventilation if necessary (with low tidal volumes)
• Many experimental therapies (antiinflammatory among others)


DDx Cardiogenic versus Non-cardiogenic


Underlying condition: Myocardial infarction vs. severe infection
• X-ray appearance
• Estimates of Pc (central venous pressure, BNP peptide)
• Measurement of Pc (Swann-Ganz Catheter)
• Measurement of Alveolar protein concentration (estimate of πi)


Hanta virus = both cardiogenic and non-cardiogenic pulmonary edema

High altitude pulmonary edema (HAPE)

cardiogenic = pulm venoconstriction
non-cardiogenic = protein in alveolar fluid

Pulmonary Edema

into the interstitium is the rate of lymphatic 

Treatment for pulmonary edema

• Decrease Preload: diuretics, sit patient up in bed, n
  • itrates, morphine, dialysis.
• Improve Cardiac Performance: Nitrates, Inotropes, 
  • Digoxin.
• Decrease Afterload: ACE inhibitors, nitroprusside
• Increase Pi: Continuous positive airway pressure, 
  • mechanical ventilation
• Decreasing LpA, or osmotic pressure has not been 
  • attempted.

Non-cardiogenic Pulmonary Edema

If there is endothelial damage Lp

increases and Jv increases

Capillary endothelium loses barrier function

– Does not require change in hemodynamics

– Forces that oppose Pc decrease

– LpA increases

– leaky capillaries and increased fluid filtration!

Treatment of non-cardiogenic pulmonary edema

Treatment / Removal of offending source (infection , aspiration , inhalation)
• Mechanical Ventilation if necessary (with low tidal volumes)
• Many experimental therapies (antiinflammatory among others)


DDx Cardiogenic versus Non-cardiogenic


Underlying condition: Myocardial infarction vs. severe infection
• X-ray appearance
• Estimates of Pc (central venous pressure, BNP peptide)
• Measurement of Pc (Swann-Ganz Catheter)
• Measurement of Alveolar protein concentration (estimate of πi)


Hanta virus = both cardiogenic and non-cardiogenic pulmonary edema

High altitude pulmonary edema (HAPE)

• cardiogenic = pulm venoconstriction
• non-cardiogenic = protein in alveolar fluid