Lecture 41 Flashcards
Adrenergic Agonists 1
1
Q
Arterial Baroreceptors
A
- Sense arterial pressure indirectly
- Stretch of the elastic arterial walls
2
Q
Epinephrine
A
- Adrenaline
- Released from chromamaffin cells of adrenal medulla (endocrine hormone)
- EPI simulations all alpha and beta receptors
3
Q
Beta 1 Mechanism Review: Fight or Flight
A
- Increased inotropic and chrontropic on heart
- Dilated coronary vessels
- Lipolysis to some extent
- Increases HR and contractility
- Increases systolic AND diastolic BP
4
Q
Beta 2 Mechanism Review: Fight or Flight
A
- Increases blood flow to skeletal muscles and vasodilation
- Dilates bronchi to increase oxygen intake
- Increases glycogenolysis in muscle/liver
- Increases gluconeogenesis in liver
5
Q
Beta 3 Mechanism Review: Fight or Flight
A
- Lipolysis
- Relaxes detrusor muscle
6
Q
Alpha 1 Mechanism Review: Fight or Flight
A
- Vasoconstriction in skin/mesentery
- Increases systemic BP
7
Q
PK of EPI
A
- Administration via injection, intranasal, and topical to eye
- NOT ORAL (susceptible in liver metabolism)
- IV injection - slowly over 5-10 minutes during CPR
- ER use
- Loses potency after expiration date due to tendency to auto-oxidize (changes from clear to a pink or brown color)
8
Q
Epinephrine Uses
A
- Bronchi dilation
- Anaphylaxis
- Cardiopulmonary Resuscitation
- Direct intracardiac Injection
- Circulatory shock following resuscitation
- Surgical bleeding
- Decrease mucosa congestion
9
Q
Bronchi Dilation
A
- Beta 2 receptor activation
- Treats bronchospasm and severe asthma exacerbation
- Anaphylaxis ==> Use Epipen Autoinjector
- Ana-Kit: SC, IM, IV
- Primatene - OTC inhlaer (D/C due to chlorofluorocarbons)
- Racepinephrine (Asthmanetrin) - OTC inhaler, temporary relief of mild symptoms of intermittent asthma
10
Q
EPI: Antagonist of Histamine
A
- Vasoconstricts: decreases mucosal edema (alpha-1)
- Dilates bronchi (Beta-2)
- Stabilizes mast cells - increases histamine release (Beta-2)
11
Q
Histamine’s Role in Allergy
A
- Dilates and increases permeability of capillaries (edema)
- Constricts smooth muscle of bronchi
- Stimulation of mucus secretions
12
Q
Cardiac Resuscitation -Target/Drug
A
- Beta 1 receptor = cardiac
- Ana-Kit used in cardiac resuscitation
13
Q
Cardiac Arrest Causes
A
- Tachyarrhythmias
- Bradyarrhythmias (Decrease HR and AC conductance)
- Asystole - no HR/contraction
14
Q
Cardiac Resuscitation Steps
A
- First start CPR with electrical defibrillation
- EPI and vasopressin used to constrict blood vessels (alpha 1 effect and V1 receptors)
- Main purpose of epi/vasopressin is to increases cerebral/myocardial blood flow during CPR
- Antiarrhythmic drugs (amiodarone/lidocaine)
15
Q
Direct Intracardiac Injection
A
- Only in extreme emergencies
- Risks include: myocardial puncture, coronary artery rupture, pneumothorax
16
Q
Circulatory Shock
A
- Can occur after resuscitation
- IV infuse EPI for symptomatic bradycardia treatment
- Dopamine is first line preferable
- EPI increases the changes of spontaneous circulation