Acute HF (Newman) Flashcards
3 neurohumoral systems activated in HF
renin
Naturetic peptides
symp system
Major determinants of afterload
systolic BP
size of ventricle
3 contraindications to heart transplant
> 65 yo
systemic disease
drug addicts/compliance
circumstance in which O2 delivery to the tissues is in adequate relative to their O2 requirements
heart failure
causes of acute heart failure
** DECREASED CONTRACTILITY**
–> dec CO and O2 delivery
acute MI
exacerbation of chronic HF
post operative
signs and symptoms of acute HF
dyspnea and fatigue pulmonary congestion dec BP cold extremities dec urine output
removing functional myocytes will decrease ____
contractility
Ejection fraction in acute HF
less than 50%
* on test?
how to measure O2 utilization
O2 in arterial blood - O2 in venous blood of a specific tissue
= arterial venous difference
normal tissues extract ___% of the O2 delivered to them
25%
**blood leaves heart 100% and returns to the pulmonary artery/RT heart at 70%
if the tissues extract way more than 25% O2 we know…
person is in HF
As CO decreases the amt of extraction of O2 (increases or decreases)
increases (From 3%0 to 60%)
**measure wil mixed venous something rather
In AHF, how is perfusion to the brain maintained?
vasoconstriction at kidneys, skin = limit blood flow to kidney and ~give to brian
A normal person and a HF pt have the same MAP. How is this possible?
the person in HF has very high TPR
When will the BP drop in HR causing shock?
when the TPR can no longer maintain BP