Hemodynamics Flashcards
stroke vol
def?
healthy vol?
avg vol?
amt of blood ejected by the each ventricle with each beat
- 60 to 130mL
- 70 to 80mL
preload result of low preload? relation with SV relationship with diastole avg pressure
amt of blood in each ventricle before contraction
- leads to low BP–> hypovolemic shock
- positive rel
- both at rest when in this phase
- 120/80mmHg
Afterload
-high force? causes? fix?
low force? cause? fix? result?
pressure rqd to open valves to eject blood that fills the ventricles
-aortic and pulmonary valve
high BP, caused by fatty deposits, plaque formation, anything that constricts the lumen. fix with med and life changes
-low BP, caused by dehydration, hypovolemia, fix with increasing bodily fluids and constricting the lumen-meds
contractility
result of low contractility, to fix?
the squeeze of ventricle muscles to squeeze blood thru aortic and pulmonary valve to the body
-CHF, reduce with lasix
what causes low contractility
sedentary lifestyle, food choice, and age
diseases that causes low contractility
medication that helps
fibrosis cardiomyopathy heart attack all lead to heart failure digoxin
compliance
how stiff the ventricles can become
factors that affect SV
afterload, preload, contractility
Frank-Starling Law
states that as the volume of blood sent to the ventricles by the end of diastole increases, the heart stretches more, and has to contract more to push the blood out
-high preload= high contractility and afterload–> high systole
what causes a low preload
anything that causes excessive loss of fluids
-N&V, D, excessive loss of blood, dehydration
relationship with afterload and sv
increase pressure, e.g. vasoconstrict, afterload incr, SV dec.
relationship with afterload and sv
increase pressure, e.g. vasoconstrict, afterload incr, SV dec.
CO normal AVG what inc? what dec?
amt if blood the heart ejects/min HR*SV 3500-8000mL/min 5500 increased by ex, flight/fight, stress hyposhock when really down, decreased by fluid loss, dehydrated
MAP
normal
avg
formula
how well the heart is perfusing tissue organs
avg pressure in arteries during one cardiac cycle
normal: 70 to 100mmHG
avg=60
[SBP+ 2(DBP)]/3
