Autonomics V Flashcards
What are the receptors that epinepherine acts on?
alpha and beta receptors
Small doses of epinepherine act on what two receptors? What does this elicit?
Beta 1, increases pulse pressure, HR, SV, and CO
Beta 2-decrease TPR
Moderate doses of epinepherine act on what receptors? What does this elicit?
Beta 1 increased pulse pressure
Beta 2 -decrease TPR (slight)
Alpha 1 increased TPR (larger)
Higher doses of epinepherine act on what receptors? What does this elicit?
mainly alpha 1 to increase TPR
Why is it that epinepherine works on the beta receptors at low doses, but at high doses the alpha receptors dominate?
More specific to beta
What is the effect of administration of epinephrine SQ?
local vasoconstriction
What is the effect of epinepherine on the heart? What is the receptor utilized here?
Tachycarida–beta 1
What is phentolamine?
Alpha receptor blocker
What happens to BP if you give Phentolamine before epinepherine? Why?
Phen before epi = decreased BP since beta 2 effect of epi predominates
What are the types of drugs that pts may be taking that contraindicate epinepherine?
alpha 1 blockers
What happens if you administer epi to a pt taking beta blockers?
Overshoot BP
What is the main site of action for epinephrine as far as TPR goes?
Arterioles and precapillary sphincters
What happens with cutaneous blood flow with epi administration?
Redistribution of blood flow
What happens with blood flow to muscles with epinepherine administration?
Increased
What happes to cerebral blood flow with epinepherine administration?
No effect
What happes to renal blood flow with epinepherine administration?
Decreased
What happes to coronary blood flow with epinepherine administration?
Increased
What does inotropy mean?
Contraction process
What does lusitropy mean?
Relaxation process
What is the effect of epi on vascular smooth muscle?
Contraction
Are beta blockers a concern when using epinephrine locally?
No
What are the receptors that NE works on?
Beta 1 and alpha
Does NE have much effect on beta 2 receptors?
No
What is the effect of NE on TPR?
Increases
What is the effect of NE on SBP? DBP? Pulse pressure?
Increases