Autonomic Nervous System

1. Autonomic Nervous System Chapter 17,18, 19, 20

2. Central Nervous System or CNS • Brain and spinal cord: receives and processes incoming sensory information and responds by sending out signals that initiate or modify a process.

3. Peripheral Nervous System • Includes all the neurons and ganglia found outside the CNS • Includes the • Sympathetic receptors (adrenergic) • Parasympathetic receptors (cholinergic)

5. Sympathetic Nervous System • Helps the body cope with external stimuli and functions during stress (triggers the flight or fight response) • Vasoconstriction – increase in blood pressure • Increased heart rate • Increased respiratory rate • Cold, sweaty palms • Pupil dilation

6. Sympathetic Nervous System

7. Parasympathetic Nervous System • Works to save energy, aids in digestion, and supports restorative, resting body functions. • Decrease in heart rate • Increased gastro intestinal tract tone and peristalsis • Urinary sphincter relaxation • Vasodilation – decrease in blood pressure

8. The Race Horse and the Cow Sympathetic Nervous System Parasympathetic

9. Norepinephrine and epinephrine • Both always present in the blood. • Norepinephrine varies according to the amount of stress present and will cause transient changes in heart rate and systemic arteries and veins. • Epinephrine is a constant in regulating heart rate, vasoconstriction in systemic arteries and veins and vasodilation of muscles and liver.

10. Adrenergic Receptors • Norepinephrine produces its effects by combining with adrenergic receptors • Alpha • Beta

11. Adrenergic Receptors • Found in: • Cardiovascular • Endocrine • Gastrointestinal • Genitourinary • Respiratory • Ocular

12. Alpha Receptors • Alpha 1: adrenergic receptors located on postsynaptic effector cells. • Smooth muscles of blood vessels: Constriction • Bladder sphincter • Penis • Uterus • Pupillary muscles of iris

13. Adrenergic Receptor • Alpha 1 • Therapeutic Uses • Control topical superficial bleeding • Treat nasal congestion • Elevate blood pressure • Delay absorption of local anesthesia • Decrease intraocular pressure (pressure in eye)

14. Alpha 2 • Same as the Alpha 1 but are located in the presynaptic nerve terminals.

15. Adrenergic Receptor • Beta 1 • Cardiovascular • Cardiac muscle: increased contractility • Atrioventricular node (AV): increased heart rate • Sinoatrial node: increase (SA) in heart rate • Endocrine • Pancreas (insulin)

16. Cardiac Conduction System

17. Beta 1 Drugs • Predominately works on vascular smooth muscle of the heart.

18. Adrenergic Receptor • Beta 2 • Cardiovascular • Dilation of blood vessels • Endocrine • Uterine relaxation • Respiratory: dilation of bronchial muscles

19. Beta 2 Drugs • Used in Asthma to relieve bronchocontriction. • Used to delay pre-term labor by relaxing the uterus.

20. Dopamine • Adrenergic neurotransmitter – essential for normal brain function. • Studies focus on connection between dopamine malfunction in schizophrenia and Parkinson’s Disease. • Role of dopamine: stimulants and depressants.

21. Body Responses – “fight or flight” • Increase in blood pressure and cardiac output. • Increase blood flow to brain, heart and skeletal muscles. • Decrease blood flow to skin and organs not needed for “fight”. • Increase in glycogen for energy, mental activity, muscle strength, blood coagulation, respiratory rate, pupil dilation to aid vision, and increase in sweating.

22. Fight of Flight Response • Can be a problem if the body stay in the “fight or flight” mode. • Type A personalities? • High stress environment? • Medications may be needed reduce the physiologic body responses.

23. Parasympathetic Nervous System Rest and Digest Save energy Decreased heart rate

24. Sympathetic Nervous System • Protective mechanisms designed to help person cope with the stress or get away from it.

25. Body Responses – “rest and digest” • Dilation of blood vessels in skin • Decrease heart rate • Increase secretion of digestive enzymes • Constriction of smooth muscle of bronchi • Increase in sweat glands - cooling • Contraction of smooth muscles of urinary bladder • Contraction of smooth muscle of skeletal system

26. Adrenergic Drugs • What do they do? • Stimulation of the sympathetic nervous system.

27. Indications • Respiratory conditions • Topical nasal congestion • Ophthalmic conditions • Cardiovascular

28. Lungs Asthma and COPD (Chronic Obstructive Pulmonary Disease): Beta 2 drugs or bronchodilators are used to relieve broncho-constriction and broncho-spasm. Action: dilation of bronchioles

29. Asthma

30. OTC Adrenergic Drugs • Common cold: anti-histamines • Allergy: nasal or oral to relieve nasal congestion

31. Heart • Direct stimulation of receptors • Alpha 1 – • Vasoconstriction of blood vessels which increases blood pressure • Pressor or vasopressor effect to maintain blood pressure • Beta 1 • Increased force of myocardial contraction • Increased speed of electrical conduction in the heart.

32. Heart: SA Node

33. Ophthalmic Conditions • Used to reduce intraocular pressure in treatment of glaucoma.

34. Glaucoma

35. Contraindications • Only contraindications to use of adrenergic drugs are: • Drug allergy • Severe hypertension

36. Adrenergic Drugs • Epinephrine • Pseudoephedrine – Sudafed • Isoproterenol (Isuprel) • Phenylephrine (Neo-Synephrine) • Clonidine (antihypertensive)

37. pseudoephedrine • Trade names: Sudafed, Afrin nose spray • Functional Classification: Adrenergic • Therapeutic classification: allergy, cold and cough remedies, nasal drying agents / decongestants • Action: stimulates alpha and beta adrenergic receptors

39. Forms and Dosage • How supplied: tabs, chew tabs, extended release tabs, liquid or drops • Dosing: 30 to 60 mg / dose q 6-8 hours PO • Maximum dose 240 mg/24 hours • Sustained release: 120 mg PO q 12 hours

40. Contraindications • Severe Hypertension • Severe coronary artery disease (CAD) • Use with caution in pregnancy, breast feeding and renal failure

41. Side Effects • Dizziness, nervousness, restlessness, insomnia and arrhythmias • Seizures • Cardiovascular collapse

42. Additional Information • Primarily excreted renally – adjust in patients with renal impairment • May cause false-positive for amphetamines – athletes • Currently need to ask pharmacist for Sudafed – OTC has been limited due to abuse

43. Nursing Implications • Assess for congestion • Monitor pulse and blood pressure before beginning therapy • Assess lung sound for signs of bronchial secretions

44. Allergies

45. Anaphylactic Shock

46. Epinephrine • Epinephrine would be the drug of choice • Classification: Adrenergic • Action: affects both the beta 1 (cardiac) and beta 2 (pulmonary) receptors • produces bronchodilation • inhibits hypersensitivity reaction of mast cells.

47. Epinephrine • Therapeutic Effects: • Bronchodilation • Maintenance of heart rate and blood pressure • Adverse Side Effects: • Nervousness, restlessness, tremors, angina, arrhythmias, hypertension, tachycardia

48. How it is given? • Sub-Q or IV or inhaled • Epi-pen is given to clients with severe allergy reactions • Not given by mouth because drug is inactivated by gastric juices • Can be inhaled in asthma attack