Autonomic NS 3: Noradrenaline & Isoprenaline Flashcards
oral adminstration of Noradrenaline
ineffective
Explain why Noradrenaline is not given Subcutaneous or Intramuscular
It’s a strong rapid vasoconstrictor
—> Necrosis
Noradrenaline is only adminstrated by
IV infusion
effect of Noradrenaline on the Heart
Reflex Bradycardia, caused by:
* sudden increase in blood pressure caused by increased Vasoconstriction
* Vagal stimulation
this maskes the effect noradrenaline has on Beta 1
Reflex Bradycardia caused by Noradrenaline can be antagonised by
Atropine;
* Atropine is parasympatholytic, preventing vagal stimulation, preventing the reflex
effect of Noradrenaline on Blood pressure
Increases both systolic & diastolic
IV infusion dosage of Noradrenaline
1/1000 diluted in saline/ glucose
+
Monitor BP & ECG
explain why IV infusion of Noradrenaline shouldn’t be suddenly stopped
to avoid sudden drop in blood pressure
Noradrenaline after atropine leads to
Tachycardia (Beta 1)
receptors stimulated by Isoprenaline
Beta 1 & Beta 2
effect of Isoprenaline on the heart
Increase all Cardiac properties
effect of Isoprenaline on the blood vessels
Vasodilatation of Skeletal & Coronary vessels
No VC (Alpha 1)
effect of Isoprenaline on blood pressure
general Hypotension
* decreases Diastolic bp (due to VD of skeletal & coronary vessels)
effect of Isoprenaline on bronchi
brochodilatation
effect of Isoprenaline on GIT
relaxation of walls
