Chapter 20 Part 3 Flashcards
amount pumped by each ventricle in 1 minute
cardiac output
HR=
number of beats per minute
volume of blood pumped out by 1 ventricle with each beat. correlates with force of ventricular contraction
stroke volume
hr x sv=
co
entire blood supply passes through each side of the heat ``
1x/min
what side is pulmonary congestion on
left
left sided heart failure=
pulmonary congestion
in pulmonary congestion what side is fully functioning
right, but left has inadequate ejection
blood vessels in lungs fill with blood, pressure increases and fluid leaks from BV into lung tissue->
pulmonary edema-> suffocation
right sided heart failure=
peripheral congestion
blood is stagnant in peripheral congestion which means
fluids pool in tissue spaces and body impaired to obtain adequate nutrients and O2/ remove wastes. swelling in extremities
failure of 1 side= strain on other side->
complete heart failure
how do you treat congestion
diuretics, decrease BP, digitalis, heart transplant
if sudden drop in BV or heart weak->
SV drops and CO maintained via increase in HR and contractility
temporary stressors influence
HR via homeostatic mechanisms: neural, chemical and physical
factors that increase HR=
+ chronotropic factors
neg vice versa
normal hr
60-100
tachycardia
> 100 due to stress, elevated temp, drugs
bradycardia
<60 due to low temp, drugs or PNS. May warn of brain edema after head trauma
most important extrinsic control affecting HR
ans
emotional or physical stressord activates
SNS
whats is released at cardiac synapses
Ne
ans binds to beta 1 adrenergic receptors in heart which means
threshold reaches quicker
SA node fires more rapidly and heart
beats faster
