Shock part 3 lecture Flashcards
Alpha 1 is in vascular smooth muscle cells which increases TPR and increases blood pressure
If you stimulate B1 receptor which increases heart rate, increase contractility, and increases AV conduction
B2 is in vascular smooth muscle cells but airway smooth muscle cells and cause airway dilation that’s only relevant though during analphatic shock but for other types of shock that’s usually not the issue…drugs may cause bronchodilator but that’s not going to save your patients unless the patient is undergo anaphylactic shock so that’s just an added benefit of that
Fight or flight causes vasoconstriction and vasodilation, squeezing blood out of nonessential organs and dilating in the blood vessels going into essential organs so diverting blood in the essential organs and putting them to essential organs like skeletal muscle
What organs do you need in fight or flight mode?
skeletal muscle
What organs don’t you need in a fight or flight mode? GI, skin, stomach, nonessential organs
Sympathomimetics (mimics fight or flight)
Catecholamine
____________
Epinephrine
Dopamine
Norepinephrine
Epinephrine,Norepineprine, and dopamine are all made from __________
tyrosine
Direct-acting sympathomomimetics aka catecholamines have a short duration of action
Dopamine is a catecholamine but dopamine receptors can be found where?
peripheral tissues
If you administer dopamine IV is it going to end up in the brain??
NO
If dopamine is administered systemically it does not significantly cross the brain brain barrier-no effects on CNS
With increasing dose,dopamine starts to bind and activate adrenergic receptor due to its structural similarity to Epi and NE—> sympathomimetic effects
Dopamine dose-dependent effects
Low dose
D1
Vasodilation
Intermediate dose of dopamine
B(1) adrengergic receptor activation
increase contractility and increase heart rate
High dose of dopamine
starts to activate alpha 1 adrengeric receptor
causes what?
vasoconstriction
