Ch. 18 & 19 Flashcards
Autonomic Nervous System:
- ) Sympathetic (Adrenergic)
2. ) Parasympathetic (Cholinergic)
Sympathetic & Parasympathetic Systems:
- ) Act on organs but produce opposite responses
- ) Drugs act by either:
- stimulating response
- depress response
Neurotransmitters:
Chemical substance:
-carries impulses from one neuron to another
Sympathetic NS:
Norepinephrine:
- Transmits impulses between postganglionic neuron & tissue receptor
Parasympathetic NS:
Acetylcholine:
-Transmits impulses between preganglionic & postganglionic neurons
Sympathetic NS (Adrenergic Branch):
- ) “Fight or flight” system
- ) Physical/Emotional stress
- ANS suppresses non vital body functions
Promotes Self-Preservation:
- ) Pupils
- ) Bronchioles dilate
- ) Increase in rate & force of heart concentration
- ) Shunt blood to major organs
- ) Breakdown of glycogen to glucose
Drugs that Affect the Autonomic NS:
- ) Sympathomimetic (adrenergic)
- Sympatholytic (adrenergic blocking) - ) Parasympathomimetic (cholinergic)
- Parasympatholytic (anticholinergic)
Adrenergics & Adrenergic Blockers:
Alpha & Beta receptors found in Sympathetic NS
Alpha 1 Receptors:
- ) Smooth muscle tissue of peripheral blood vessels
- ) Sphincter of GU tracts, prostate & bladder
- causes vasoconstriction
- control release of norepinephrine
Beta 1 Receptors (1):
Muscles of heart
-Kidneys
Beta 1 Receptors (2):
Stimulation:
1. ) Increased heart rate 2. ) More forceful heart muscle contraction
Beta 2 Receptors (1):
- ) Bronchial smooth muscles
2. ) Walls of blood vessels, smooth muscle of the GI, Lungs, Uterus
Beta 2 Receptors (2):
- Stimulation
- Bronchial muscle relaxation
- Improved gas exchange
- Tx: bronchial asthma
3 Classifications of Sympathomimetics (1):
1.) Direct-acting:
-Directly stimulate the adrenergic receptor
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Ex: epinephrine & norepinephrine
3 Classifications of Sympathomimetics (2):
2.) Indirect-acting:
-Stimulate release of norepinephrine from terminal nerve endings
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Ex: Amphetamine
3 Classifications of Sympathomimetics (3):
3.) Mixed-acting:
(a): Stimulate adrenergic receptor sites
(b): Stimulate release of norepinephrine from terminal nerve endings
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Ex: pseudoephedrine
Nonselective Sympathomimetics:
- ) Excite all receptors equally
2. ) More side effects occur
Nonselective Sympathomimetics - Ex: epinephrine(1):
- ) Good for emergency situations
2. ) Increased BP, heart rate, & airflow through lungs
Nonselective Sympathomimetics - Ex: epinephrine(2):
SE:
-Anorexia, N/V, nervousness, tremors, HA, insomnia, syncope, dizziness
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Adverse Reactions:
-Palpitations, tachycardia, dsypnea, ventricular fibrillation
Selective Sympathomimetics:
- ) Acts on specific receptors
2. ) Less side effects because more specific
Selective Sympathomimetics - Ex: albuterol sulfate (Proventil) (1):
- ) Selective for beta 2-adrenergic receptors
2. ) Acts on bronchi for bronchodilation
Selective Sympathomimetics - Ex: albuterol sulfate (Proventil) (2):
Asthmatic –> better to take
-albuterol (acts on beta 2) –> fewer undesired effects
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High doses (may affect beta 1 receptors) –> cardiac SE
Selective Sympathomimetics - Ex: albuterol sulfate (Proventil) (3):
Used to prevent/tx bronchospasms
— inhalation, po
Ex: albuterol sulfate (Proventil):
SE:
-Tremors, dizziness, nervousness, restless
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Adverse Reactions:
-Palpitations, tachycardia, cardiac dysrhythmias
Adrenergic Blockers (Sympatholytics, Adrenergic Antagonists):
- ) Block effects of adrenergic neurotransmitters
- ) Antagonists to adrenergic agonists (sympathomimetics)
- blocking either alpha- or beta- receptor sites
Alpha - Adrenergic Blockers:
1.) Selective or Nonselective
2.) Cause vasodilation —> decreased
-BP (dizziness) –> pulse rate increases to compensate (good for PVD)
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Tx: peripheral vascular disease
Beta-Adrenergic Blockers (beta blockers) (1):
Decrease heart rate —> decrease blood pressure
-Selective or Nonselective
Beta-Adrenergic Blockers (beta blockers) (2):
causes bronchoconstriction
-Ex: propranolol (inderal)
Beta-Adrenergic Blockers (beta blockers:
metoprolol tartrate (Lopressor)
- Good for resp pts
———————————————–
drug is more selective beta-1 blocker
Main Uses for Cholinergic Drugs:
- ) Stimulate bladder and GI tone
- ) Constrict pupils
- ) Increase neuromuscular transmission
Anticholinergics (parasympatholytic) (1):
Inhibit action or acetylcholine
Anticholinergics (parasympatholytic) (2):
Main body tissues/organs affected:
- ) Heart
- ) Respiratory Tract
- ) GI Tract
- ) Urinary Bladder
- ) Eyes
- ) Exocrine Glands
Anticholinergic Drugs:
May cause problems:
- Bronchial asthma - Benign prostatic hypertrophy (BPH)
Anticholinergic Drugs - Ex: Atropine sulfate:
Derived from:
-Atropa Belladonna plant
Atropine sulfate (1):
Reduces:
- ) Motility of GI tract
- ) Secretions of saliva
- ) Bronchial secretions
- Sweat
Atropine sulfate (2):
- ) Dilates pupils
- ) Interferes with ability of eye to focus
- ) **Contraindicated in clients w/ narrow angle glaucoma
- ) May increase pressure within the eye
Atropine sulfate (3):
Promotes retention of urine by the bladder
Not for men with BPH
Major SE: Anticholinergics (1):
- ) Dry mouth
- ) Constipation
- ) Urinary Tension
- ) Blurred Vision
- ) Photophobia
- ) Headache
Major SE: Anticholinergics (2):
- ) Can’t see
- ) Can’t spit
- ) Can’t pee
- ) Can’t shit
Synthetic Anticholinergics:
Less likely to affect pupils compared to natural derivatives
Ex: glycopyrrolate (Robinul)
Nursing Interventions (anticholinergics) (1):
DO NOT give to clients with:
- ) Narrow angle glaucoma
- ) BPH
- ) Geriatric clients
Nursing Interventions (anticholinergics) (2):
Call physician if:
- ) Blurred visions
- ) headaches
- ) Urinary retention
- ) Palpitations
Nursing Interventions (anticholinergics):
- ) Monitor bowel sounds
- ) Encourage adequate fluid intake
- ) Help relieve dry mouth:
- Mouth Care
- Hard Candy
