Adrenergic Agonists and Antagonists Flashcards
Epinephrine
Low dose physiological effects
Lower diastolic BP (B2) Increase CO (B1)
Epinephrine
High dose physiological effects
Increase TPR and CO (A1, A2, B1)
Bronchodilation (B2)
Decreased bronchial secretions (A1)
Epinephrine
Toxicity
Arrhythmias cerebral hemorrhage anxiety cold extremities pulmonary edema
Epinephrine
Indiciations
Anaphylaxis
Cardiac Arrest
Bronchospasm
Norepinephrine
Physiological Effects
Increase CO (B1) Increase TPR (A1, A2) Decrease HR (baroreflex) Overall increase MAP
Norepinephrine
Toxicity
Ischemia
Arrhythmias
HTN
Norepinephrine
Indications
Shock
Norepinephrine
Contraindications
Preexisting ischemic or vasoconstriction
Isoproterenol
Physiological Effects
Nonspecific B agonist Decrease TPR (B2) Increase CO (B1) Small decrease in MAP Bronchodilation (B2)
Isoproterenol
Indications
Bradycardia/heart block when TPR is high
Iroproterenol
Toxicity
Tachyarrhythmias
Isoproterenol
Contraindications
Angina with arrhythmias
Dobutamine
Physiological Effects
Selective B1 agonist Increase CO (B1)
Dobutamine
Toxicity
Hypotension (B2)
Arrhythmias (B1)
Dobutamine
Indications
Short term Rx for CHF or cardiogenic shock
Dopamine
Physiological Effects
Low Dose
Decrease TPR (D1 - vasodilation of renal and splanchnic circulation) Increases CO (B1)
Dopamine
Physiological Effects
High dose
Increases MAP and TPR (A1, A2, B1)
Dopamine
Toxicity
Low BP (low infusion rates) Ischemia (high infusion rates)
Dopamine
Indications
Cardiogenic Shock
Dopamine
Contraindications
Tachyarrhythmias
Ventricular fibrillation
Alpha-1 receptors located?
Vascular smooth muscle (contraction)
Pupillary dilation
Alpha-2 receptors located?
Adrenergic and cholinergic nerve terminals (inhibit NT release)
Beta-1 receptors located?
Heart (cardiac myocytes and SA pacemaker cells) Juxtaglomerular apparatus (increase renin release)
Beta-2 receptors located?
Vascular smooth muscle
Uterine smooth muscle
Respiratory smooth muscle
DILATION
