Sympathomimetic- Norepinephrine Flashcards
NE receptors
a1 a2 b1
minimal b2 per flood
what medication is the immediate precursor to EPI
NE
NE activates beta 1 which increases what 3 things in the heart
HR, conduction, and contractility
NE is a potent alpha 1 agonist - what are the effects
intense arterial and venous vasoconstriction in all vascular beds
does NE vasoconstrict the coronary arteries
no
NE causes greater increase in what 4 things related to BP compared to EPI
SVR, SBP, DBP & MAP
NE heart rate change is minimal due to what
baroreceptor reflexes triggered by arterial vasoconstriction are counter acted by beta 1 mediated increases in HR
EPI or NE has a greater chronotropic effect
EPI
higher doses of NE- what effect predominates
vasoconstriction
NE and EPI increases total peripheral vascular resistance more than which drug
dobutamine
what are the NE metabolic effects
minimal
what are the effects in the blood sugar with NE
hyperglycemia is unlikely
IV NE has intense vasoconstriction of what body systems
skeletal muscle
liver
kidneys
skin vascular beds
NE has peripheral vasoconstriction such that what condition is seen
metabolic acidosis
continuous infusion of NE dose
2-16mcg/min
why do we place NE in a 5% glucose solution
prevents oxidation of the drug
chronic infusion or increase in circulation of NE may be associated with what three things
pheochromocytoma
precapillary vasoconstriction
loss of protein free fluid into the extracellular spcae
what additional monitoring is needed with NE
hemodynamic monitoring
what additional vascular access do we need with NE
CVL- due to risk of extravasation
metabolism of NE
eliminated by REUPTAKE into the ADRENERGIC NERVE ENDINGS where it is stored for future release
- only small amounts are metabolized
NE is a first line agent to treat
refractory hypotension during severe sepsis
after a CABG- why give NE
treat low systemic vascular resistance
what is the primary use for NE
potent vasoconstrictor to increase PVR and MAP
NE effects in splanchnic blood flow and UOP in severely hypotensive septic patients
increase in blood flow and urine output
Why is NE used cautiously in patients with RV failure
alpha effects of…
increases PAWP
increases right partial pressure
NE and increased peripheral resistance and increased after load will result in what
decreased CO and increase work of LV
NE & hr
may cause tachycardia- more seen with EPI
side effect of NE
organ ischemia
NE and renal effects
renal arterial vasoconstriction may lead to oliguria and renal failure
large doses of NE and adequate fluids volume resuscitation can do what to renal blood flow
increase perfusion pressure of renal blood flow
how does NE augment stroke volume and CO
vasoconstriction and increase venous return due to decrease venous capacitance
(The measure of a BLOOD VESSEL’s ability to increase the volume of BLOOD it holds without a large increase in BLOOD PRESSURE. Thevascular capacitanceis equal to the change in volume divided by the change in pressure).
