AUTONOMIC NERVOUS SYSTEM imp ppt

AUTONOMIC NERVOUS SYSTEM PPT

1. Autonomic Nervous
System
Prepared by:
MR.VIJAYREDDY VANDALI
VICE-PRINCIPAL
SCHOOL OF NURSING
P P SAVANI UNIVERSITY
SURAT

4. Nervous SystemNervous System
Central Nervous System (CNS) - Brain and
spinal cord
Peripheral Nervous System (PNS) - Located
outside the brain & spinal cord
* Autonomic Nervous System (ANS) &
the somatic
The PNS receives stimuli from the CNS &
initiates responses to the stimuli after it’s
interpreted by the brain

5. Autonomic Nervous SystemAutonomic Nervous System
ANS acts on smooth muscles & glands
- Controls & regulation of the heart,
respiratory. system, GI tract, bladder,
eyes & glands
- Involuntary - person has little or no
control
Somatic - voluntary - person has control
(skeletal muscle)

6. ANSANS
ANS has 2 sets of neurons:
1. Afferent (sensory) - sends impulses to
the CNS for interpretation
2. Efferent - receives impulses (info.) from
the brain & transmits from the spinal
cord to the effector organ cells
- 2 branches - sympathetic &
parasympathetic nervous system

7. Functions of ANSFunctions of ANS
Sympathetic and parasympathetic divisions typically Sympathetic and parasympathetic divisions typically
function in opposition to each other. But this opposition function in opposition to each other. But this opposition
is better termed complementary in nature rather than is better termed complementary in nature rather than
antagonistic. For an analogy.antagonistic. For an analogy.
one may think of the sympathetic division as the one may think of the sympathetic division as the
accelerator and the parasympathetic division as the accelerator and the parasympathetic division as the
brake. brake.
The sympathetic division typically functions in actions The sympathetic division typically functions in actions
requiring quick responses. The parasympathetic division requiring quick responses. The parasympathetic division
functions with actions that do not require immediate functions with actions that do not require immediate
reaction. Consider sympathetic as "fight or flight" and reaction. Consider sympathetic as "fight or flight" and
parasympathetic as "rest and digparasympathetic as "rest and digest".est".

10. Figure 20-2.
Sympathetic and Parasympathetic Effects on Body Tissues

14. ANS - Sympathetic nervous ANS - Sympathetic nervous
system (Adrenergic) system (Adrenergic)
Sympathetic Nervous System (adrenergic)
Norepinephrine = neurotransmitter
- Drugs that mimic = adrenergic drugs,
sympathomimetics, or adrenomemetics
* Adrenergic agonists - Drugs initiate a
response
- Drugs that block = adrenergic blockers,
sympatholytics or adrenolytics
* Adrenergic antagonists - prevent a response

16. ANSANS
4 types of adrenergic receptor organ cells:
1. Alpha-1 = vasoconstriction of blood vessels
inc. blood return to heart, inc. circulation, inc. BP
2. Alpha-2 = inhibits release of norepinephrine
dec. in vasoconstriction, dec. BP
3. Beta-1 = inc. in heart rate & force on contraction
4. Beta-2 = relaxation of smooth muscle in bronchi,
uterus, peripheral blood vessels
Dopaminergic = dilate vessels, inc. in blood flow - only
dopamine activates this receptor

17. ANS - Parasympathetic Nervous ANS - Parasympathetic Nervous
System (Cholinergic) System (Cholinergic)
Parasympathetic or Cholinergic Nervous
System
Acetylcholine = neurotransmitter
- Drugs that mimic = cholinergic drugs,
parasympathomimetics
Cholinergic agonists - initiates a response
- Drugs that block = anticholinergic,
parasympatholytics
Cholinergic antagonists - prevents a response

18. ANSANS
Sympathomimetic
pathway
Norepinephrine
From adrenergic fiber
Inc. heart rate
Pupil dilation
Adrenergic
(sympathomimetic)
agents
Fight or Flight
Parasymathomimetic
pathway
Acetylcholine
From cholinergic fibers
Dec. heart rate
pupil constriction
Cholinergic
(parasympathomimetic
agents)

21. Chapter 21: Adrenergics and Chapter 21: Adrenergics and
Adrenergic BlockersAdrenergic Blockers
Drugs that Stimulate the sympathetic Nervous
System (adrenergics, adrenergic agonists,
sypathomimetics, or adrenomimetics)
Mimic the sympathetic neruotransmitters
norepinephrine and epinephrine
Act on one or more adrenergic receptor sites
located on the cells of smooth muscles -
heart, bronchioles, GI tract, bladder, eye
4 main receptors (alpha-1, alpha-2, beta-1,
beta-2)

22. SYMPATHETIC RESPONSESSYMPATHETIC RESPONSES

23. Sympathomimetics/Sympathomimetics/
AdrenomimeticsAdrenomimetics
Stimulate adrenergic receptors: 3 categories
1. Direct-acting = directly stimulates receptors
(epinephrine or norepinephrine)
2. Indirect-acting = stimulates release of norep.
from terminal nerve endings (amphetamine)
3. Mixed-acting (indirect & direct) = stimulates
receptor sites & release of norep. from nerve
endings (Ephedrine)

24. Sympathomimetic Agents/ Sympathomimetic Agents/
AdrenergicsAdrenergics
Action - Many of the adrenergic drugs
stimulate more than one of the adrenergic
receptor sites (alpha & Beta)
Response = Inc. BP, pupil dilation, inc. HR, &
bronchodilation
Use = Cardiac stimulation, bronchodilator,
decongestant
Side effects = Hyperness in body

25. Sympathomimetics/AdrenergicsSympathomimetics/Adrenergics
Albuterol - Beta-2 agonist (bronchodilation)
Use - bronchospasm, asthma, bronchitis
SE - nervousness, restlessness
CI - severe cardiac disease, HTN
Epinephrine - stimulates alpha & beta
Use - allergic reaction, cardiac arrest
SE - nervousness, agitation
CI - cardiac dysrhythmias

26. Adrenergic AgentsAdrenergic Agents
Dopamine - alpha-1 & beta-1
stimulation
Use - Hypotension, shock, inc. cardiac
output, improve perfusion to vital
organs
SE - N & V, headache
CI - V. Tach

27. Adrenergic Blockers Adrenergic Blockers
(antagonists/sympatholytics)(antagonists/sympatholytics)
Block alpha & beta receptor sites
(nonselective)
direct or indirect acting on the release of
norepinephrine and epinephrine
Use - Cardiac arrthymias (HR), HTN ( cardiac
output), angina (O2 demand)
SE - CHF, bronchospasm, bradycardia,
wheezing

28. Nonselective vs Selective Beta Nonselective vs Selective Beta
blockersblockers
Nonselective have an equal inhibitory effect
on B1 & B2 receptors -
- Drugs have lots of interactions due to lots of
alpha/beta receptor sites throughout body
- use with caution on clients with cardiac
failure or asthma
Selective B1 helpful in asthma clients

29. Adrenergic Blocking AgentsAdrenergic Blocking Agents
Inderal (Propranolol) - Nonselective
Use - angina, dysrhythmias, HTN, migraines
SE - Many d/t nonselective
CI - asthma, heart block > 1st degree
Minipress (Prazosin) - A blocker
Use - mild to mod. HTN
SE - orthostatic hypotension
Tenormin (Atenolol), Lopressor (Metoprolol)
B1 (cardio) selective
Use - mild to mod HTN, angina

30. Chapter 22: Cholinergics and Chapter 22: Cholinergics and
AnticholinergicsAnticholinergics
Cholinergics stimulate the parasympathetic
nervous system
Mimic the neurotransmitter acetylcholine
2 types of cholinergic receptors
1. muscarinic - stimulates smooth muscle &
slows HR
2. nicotinic - affect skeletal muscle
Many = nonselective & affect both receptors
Some affect only the muscarinic receptors
and not the nicotinic receptors

31. Parasympathetic ResponsesParasympathetic Responses

32. Cholinergic AgentsCholinergic Agents
Direct acting - act on the receptors to
activate a tissue response
Indirect acting - inhibit the action of the
enzyme cholinesterase
(acetylcholinesterase - ACH)
Major uses = Stimulate bladder & GI
tone, constrict pupils (miosis), neuro-
muscular transmission

33. Direct-acting Parasympathomimetic Direct-acting Parasympathomimetic
(cholinergic drugs)(cholinergic drugs)

34. Cholinergic Agent Cholinergic Agent
(Parasympathomimetics)(Parasympathomimetics)
Bethanechol (Urecholine) selective to
muscarinic receptors, mimic action of
acetylcholine
Use - For urinary retention
* Take on an empty stomach d/t inc. peristalsis
* Alert- Never give IM or IV – circulatory
collapse, hypotension, shock & cardiac arrest
poss.
Pilocarpine (Pilocar) - Ophthalmic - direct
acting

35. Cholinergic Blocking AgentsCholinergic Blocking Agents
Anticholinergics/ParasympatholyticsAnticholinergics/Parasympatholytics
Drugs that inhibit action of acetylcholine
(ACH) receptors
Affects the heart, resp. tract, GI tract, bladder,
eye, & exocrine glands.
Allows the sympathetic nervous system to
dominate
Anticholinergic & cholinergic drugs have
opposite effects
Major responses = dec. in GI motility, dec. in
salivation, dilation of pupil (mydriasis), inc.
pulse rate

36. AnticholinergicsAnticholinergics
Uses: Pre-op meds,bradycardia, GI/urinary
antispasmodic
SE: Dry mouth/mucus membranes
Atropine Sulfate - Inhibits ACH blocks
vagal effects on SA & AV nodes inc.
conduction & inc. HR
Use = Bradycardia, pre-up to dec. secretions,
peptic ulcer disease
SE = Many. Most frequent = dry mouth,
blurred vision, urine retention, constipation

37. AnticholinergicsAnticholinergics
Bentyl (Dicyclomine) - Inhibits ACH on
muscarinic receptors & dec. GI motility
Use - Irritable bowel syndrome
SE - constipation, urinary retention, dry mouth
Robinul (Glycopyrrolate) - Similar to above
Use - pre-op to dec. secretions, GI disorders
SE - Similar to above

38. AnticholinergicsAnticholinergics
Anticholinergics effect the CNS & benefit
people prone to motion sickness
Scopolamine Patch - Classified as an
antihistamine for motion sickness
- Topical skin patch behind the ear x3 days
Use = cruising on water, flying, car sickness
Other drugs = Dramamine, Bonine
SE = Dry mouth, visual disturbances d/t pupil
dilation

39. THANK YOUTHANK YOU