Flash Pulmonary Edema

Today in morning report we touched on the causes of flash pulmonary edema. We haven't addressed this on the blog previously, so I thought we would go over it:

Flash pulmonary edema is a particularly sudden form of Acute Decompensated CHF (in patient without chronic CHF). Mechanism of flash pulmonary edema is a sudden increased in LV end-diastolic pressure

Classic causes of flash pulmonary Edema:

1) Primary Cardiac Problems
- Mitral stenosis: in setting of tachycardia, atrial fibrillation, or high circulating volume of pregnancy
- Acute mitral or aortic regurgitation
- Arrythmia in a patient with pre-existing diastolic dysfunction
- Sudden Pump failure: acute MI or stress-induced cardiomyopathy

2) Hypertensive Emergency

3) Renovascular
Bilateral renal artery stenosis more commonly than unilateral. Patient with RAS are predisposed to developping flash pulmonary edema because of "(i) defective natriuresis; (ii) increased haemodynamic burden and exacerbation of diastolic dysfunction and (iii) failure of the pulmonary capillary blood–gas barrier" (Messerli FH. Eur Heart J (2011) 32 (18): 2231-2235). 

Acute Treatment is centered around decreasing preload as well as afterload:
- Lasix
- (Morphine) Limiting supporting data. In theory, decreased sympathetic drive, thus leads to veno/arterial vasodilatation
- Nitroglycerin (venodilator thus reduces preload,  weaker arterial vasodilator)
- Oxygen
- P= Position (sitting up) but also Pressure (ie. Non-Invasive Positive Pressure Ventillation aka CPAP or BiPAP)

Have a great day!