Chapter 17 Adrenergic Agonists

Front 1

Therapeutic Applications of Alpha1 activation

Back 1

-Vasoconstriction
- Mydriasis (pupil dilation)

Front 2

Vasoconstriction can cause

Back 2

-Hemostasis- stopping bleeding
-Nasal decongestion
-Adjunct to Lacal Anesthetics to delay absorption by reducing blood flow to the site of administration prolonging anesthesia
-Elevates blood pressure

Front 3

Clinical consequences of Alpha2 activation

Back 3

inhibits norepinephrine release- no clinical applications related to the activation of Alpha2

Front 4

Therapeutic applications of Beta1 activation

Back 4

-Increases the force of contraction in heart failure and improves cardiac performance
-Increases heart rate and force of contraction and improve tissue perfusion in shock
-Enhances impulse conduction through the AV node helping overcome atrioventricular heart block (only temporary)
-Initiate contraction in a heart that has stopped beating in cardiac arrest (not the drug of choice)

Front 5

Adverse effects of Beta1 activation

Back 5

- tachycardia from overstimulation
-Dysrhythmias from overstimulation
- Angina Pectoris, pain in the chest from not enough oxygen to meet demands

Front 6

Therapeutic Applications of Beta2 activation

Back 6

-Asthma- promotes bronchodilation to help relieve or prevent asthma attacks
-Delay of preterm labor- relaxes uterine smooth muscle

Front 7

Adverse effects of Beta2 activation

Back 7

-Hyperglycemia-promotes breakdown of glycogen into glucose in patients with diabetes
-Tremor- most common side effect due to enhanced muscle contraction

Front 8

Treatment of Anaphylactic Shock

Back 8

Epinephrine injected IM
-activates 3 types of adrenergic receptors alpha1, beta1, and beta2
-increases cardiac output, increases bp, dilates bronchioles

Front 9

Therapeutic uses of epinephrine

Back 9

-Delays absorption of local anesthetics
-Controls superficial bleeding
-Elevates BP
-Overcomes AV heart block
-Restores cardiac function in cardiac arrest
-Promotes bronchodilation
-Treatment of choice for anaphylactic shock

Front 10

Epinephrine cannot be given __________________

Inactivation of epinephine

Back 10

-Orally

-Has a short half life because of enzymatic inactivation and uptake into adrenergic nerves

Front 11

Adverse effects of Epinephrine

Back 11

-Hypertensive crisis (need continuous cardiac monitoring)
-Dysrhythmias due to excessive activation of beta1 receptors
-Angina Pectoris
-Necrosis Following extravasation of IV line
-Hyperglycemia in diabetic patients

Front 12

Epinephrine Drug Interactions

Back 12

-MAO inhibitors- prolong and intensify epinephrine
-Tricyclic Antidepressants- intensify and prolong epinephrine
-General Anesthetics- can cause tachydysrhythmias
-Alpha-Adrenergic Blocking agents- prevent receptor activation by epinephrine
-Beta-Adrenergic Blocking Agents- prevent receptor activation by epinephrine

Front 13

How does Norepinephrine and Epinephrine Differ?

Back 13

NE does not activate beta2 receptors

NE has limited clinical applications only ones are:
--hypotensive states
--cardiac arrest

Front 14

Isoproterenol (activates beta receptors) Therapeutic uses

Back 14

Cardiovascular
-AV heart block
-Cardiac arrest
-Shock

Prevents bronchospasm during anesthesia

Front 15

Adverse effects of Isoproterenol

Back 15

-tachydysrhythmias
-angina pectoris
-hyperglycemia in diabetics

Front 16

Drug interactions of Isoprotenerenol

Back 16

Same as Epinephrine
-Effects are enhanced by MAO inhibitors and tricyclic antidepressants and reduced by beta-adrenergic blocking agents

Front 17

Dopamine therapeutic uses

Back 17

-Shock
-Heart failure
-Acute Renal failure

Front 18

Adverse effects of Dopamine

Back 18

-tachycardia
-dysrhythmias
-anginal pain
-necrosis from extravasation of IV

Front 19

Drug interactions of Dopamine

Back 19

-MAO inhibitors can intensify the effects of dopamine so if taking an MAO inhibitor dopamine dose must be reduced by 90%
-Tricyclic antidepressants can also intensify dopamine's actions
-Diuretics can complement the effects of dopamine on the kidney

Front 20

Why are adrenergic agonists known as sympathomimetics?

Back 20

Their effects mimic those caused by the sympathetic nervous system

Front 21

What do you do if an IV delivering epinephrine or dopamine becomes extravasated?

Back 21

-Stop the infusion and infiltrate the region with PHENTOLAMINE to minimize injury

Front 22

Baseline data needed for dopamine preadministration assessment?

Back 22

FULL ASSESSMENT OF:
Cardiac status
Hemodynamic status
Renal Status

Front 23

How can you minimize adverse effects from dopamine and epinephrine?

Back 23

Cardiovascular effects-- reduce with a beta-adrenergic blocking agent (e.g. propranolol)

Front 24

Dobutamine therapeutic uses

Back 24

Improvement of hemodynamic status in Heart failure

Front 25

Adverse effects of dobutamine?

Back 25

tachycardia
monitor BP and ECG closely

Front 26

Drug interactions of dobutamine

Back 26

-Same as Dopamine
MAO increases effects (decrease dobutamine dose at least 90%)
-Tricyclic antidepressants may cause a moderate increase in effects

Front 27

Evaluating therapeutic effects of dobutamine

Back 27

-Monitor heart rate, ECG, blood pressure and urine output
-Monitor central venous pressure and pulmonary wedge pressure when possible