Anesthesia Pharmacology Chapter
6: Autonomic (ANS) Pharmacology
Practice Questions
Click on the correct answer.
Primary neurotransmitter released by postganglionic neurons of the autonomic sympathetic system:
- epinephrine
- dopamine
- dobutamine
- norepinephrine
- phenylephrine
Decreased heart rate following norepinephrine infusion is most likely due to:
- direct norepinephrine activation of muscarinic receptors at the SA node
- heart rate cannot decrease following norepinephrine infusion because norepinephrine activates beta-1 adrenergic receptors
- activation of the baroreceptor system causing a reflex-mediated decrease in heart rate
- peripheral vasodilation
- none of the above
Vascular effects of norepinephrine (Levophed):
- significantly decreases glomerularl filtration rates
- effective in treating variant (Prinzmetal's) angina
- norepinephrine pressor effects blocked by prazosin (Minipress)
- increased blood flow to liver, kidney, and skeletal muscle
Immediate synthetic precursor of norepinephrine:
- epinephrine
- tyrosine
- tyrosine hydroxylase
- dopamine
- dopa
CNS neurotransmitter associated with the basal ganglia and motor control:
- dopamine
- acetylcholine
- both
- neither
Low doses, this precursor of norepinephrine causes renovascular dilation:
- epinephrine
- dopa
- dopamine (Intropin)
- dobutamine (Dobutrex)
- nitroprusside sodium (Nipride)
Pharmacological action(s) of dopamine (Intropin):
- positive inotropism
- promotes myocardial norepinephrine release
- increases glomerular filtration rates (low-dose)
- vasoconstriction by alpha-1 receptor activation (high-dose)
- all the above
Significant therapeutic use for dopamine:
- management of sleep cycles
- treatment of Raynaud's phenomenon
- treatment of cardiogenic/hypovolemic shock
- management of tachyarrhythmias
Has limited action at alpha-adrenergic receptors
- phenylephrine (Neo-Synephrine)
- methoxamine (Vasoxyl)
- norepinephrine (Levophed)
- isoproterenol (Isuprel)
- prazosin (Minipress)
Effect of IV isoproterenol (Isuprel) infusions on blood pressure:
- significant vasopressor effect
- significant hypotensive effect
- slight decrease in mean pressure with a significant decrease in diastolic pressure
- significant increase in systolic pressure with minimal effect on diastolic pressure
Adverse effects associated with isoproterenol (Isuprel) administration:
- palpitations
- tachycardia
- arrhythmias
- A & C
- A,B & C