The Cardiovascular System

1. The Cardiovascular System Weeks 4 & 5

2. Anithypertensive Drugs Chapter 26

3. Hypertension (HTN) AKA high blood pressure 1 in 3 Americans have HTN May not have symptoms- pt may feel fine Hard to convince to take meds

4. Hypertension Diagnosis rarely made on a single blood pressure measurement Diagnosis made: Sustained systolic blood pressure of greater than 140 mm Hg or Diastolic pressure of greater than 90 to 99 mmHg After taking multiple measurements over several visits

5. Blood Pressure • Blood pressure is determined by these factors: • Cardiac output (CO) • Peripheral resistance (PR) • Blood Volume • Other factors can influence BP. • When renal blood flow is decreased, the RAA mechanism is activated: • Vasoconstriction and sodium and water retention

6. Classes for Hypertension • Diuretics • Centrally Acting Sympatholytic Drugs • Adrenergic Blockers • Arterial Vasodilators • Direct Acting Vasodilators • Calcium Channel Blockers • Drugs that effect the RAAS • ACE Inhibitors • Angiotensin Receptor Blockers

7. Diuretics • MOA: Increased sodium excretion • Lowers blood pressure by increasing the amount of urine produced by the kidneys • Used in mild hypertension alone • In moderate to severe hypertension the diuretics are combined with other antihypertensive drugs. • Profile Drugs: • furosemide (Lasix) • hydrochlorothiazide (HCTZ)

8. Diuretics SE/NC: • Dehydration • Monitor I&Os • Monitor for dehydration • Don’t give extra fluids unless ordered by an MD • Electrolyte Imbalance • Monitor electrolytes, especially K+ • Orthostatic Hypotension • Monitor BP • Tell pt to get up slowly

9. Centrally Acting Sympatholytic Drugs • Act directly on CNS to decrease BP • clonidine (Catapres): • MOA: • Acts directly on CNS to decrease BP • Stimulates inhibitory alpha-2 receptors • Reduces activity of nerves to heart, kidneys, and blood vessels • Use: Reduces BP • Adverse effects—dry mouth, constipation, hypotension, and drowsiness • Nursing Consideration: • Withdrawal symptoms if discontinued without tapering • Rebound HTN • Monitor BP and HR

10. Alpha, Beta, and Adrenergic Blockers • Alpha-1 blockers: • Block receptors on vascular smooth muscle • Vasodilation and decreased peripheral resistance • Beta-blockers: • Block receptors on heart, decreasing CO • Block release of renin in kidneys • Adrenergic neuronal blockers: • Prevent release of NE and deplete stored NE • MOA: • for all blocks sympathetic nervous system • causing R/D which lowers BP

11. Adrenergic Blockers SE/NC • Orthostatic Hypotension and Bradycardia • Teach pt to rise slowly • Monitor HR and BP • Hold if HR<60 and SBP<100 • Dizziness • Nausea • Bronchoconstriction • Especially for B2 Blockers or non-selective Beta-Blockers • Use cautiously in pts with COPD

12. Drugs that Reduce Sympathetic Activity • Alpha Blockers • doxazosin (Cardura) • prazosin (Minipress) • terazosin (Hytrin) • Beta Blockers • atenolol (Tenormin) • metoprolol (Lopressor) • carvedilol (Coreg)

13. Arterial Vasodilators (2 classes) • They act directly on vascular smooth muscle to cause relaxation, resulting in vasodilation (MOA). • Direct-Acting Vasodilators (one class) • Profile Drug Hydralazine (Apresoline), nitroprusside (Nipride) • They are often used in combination with diuretics and beta-blockers. • Calcium channel blockers (second class) produce arteriolar vasodilation, by interfering with the influx of CA in cardiac and smooth muscle (MOA). • Profile Drugs –See chart on next slide • Adverse effects include nausea, headache, hypotension, and reflex tachycardia.

14. Calcium Channel Blockers • Dilitiazem (Cardizem) • Verapamil (Calan) • Amlodipine (Norvasc)

15. Hypertensive Crisis Treatment • USE: • Hypertensive crisis: • Development of severe, sudden hypertension • Malignant hypertension: • Vascular inflammation • Necrosis of blood vessels • Treatment: Direct Acting Vasodilators: • diazoxide (Hyperstat) • sodium nitroprusside (Nipride) • hydralazine (Apresoline)

16. The Renin-Angiotensin Aldosterone System

17. Step by Step of the RAAS • The brain thinks the BP is too low • Renin is secreted by the kidneys, angiotensinogen is released by the liver • Renin and angiotensinogen is converted into angiotensin I • Angiotensin I is converted into angiotensin II by the agiotensin-converting enzyme • Angiotensin II has 2 primary responses: • It is a potent vasoconstrictor (raising BP) • It causes aldosterone to be released, which increases sodium reabsorption in the kidneys • Sodium reabsorption causes the body to retain water… which raises blood volume and BP

18. ACE Inhibitors • MOA: Block the ACE enzyme • Blocks the conversion of angiotensin I to angiotensin II (blocks the formation of angiotensin II) • Examples of ACE Inhibitors: • Lisinopril (Zestril) • Captopril (Capoten) • Enalapril (Vasotec) Easy way to remember if a medication is an ACE. Generic name ends in PRIL.

19. Angiotensin Receptor Blockers (ARBs) • Used to prevent angiotensin II from acting on angiotensin receptors • MOA: Block the effect of angiotensin II after it is formed Examples of ARBs: • Losartan (Cozaar) • Valsartan (Diovan) Easy way to remember if a medication is an ARB. Generic name ends in SARTAN.

20. Common side Effects for ACE inhibitors and ARBs • Hypotension • Hyperkalemia • Persistent cough (only with the ACE inhibitors)

21. Patient Education and Monitoring • Hypertension is a chronic disease requiring lifelong treatment and medical supervision. • Patients must understand the importance of taking all their medications and having regular medical checkups.

22. Preferred Therapy • Selection of therapy depends on other existing conditions: • Diuretics and beta-blockers have the longest record of proven effectiveness in treating hypertension. • ACE inhibitors and ARBs are the most frequently prescribed antihypertensive agents. • Adrenergic blocking drugs would be indicated for patients with excessive sympathetic activation.

23. Question One • The patient is on two antihypertensive drugs in one combined drug. The nurse recognizes that the advantage of multidrug treatment is: • A. Blood pressure decreases faster • B. Adverse effects are fewer and patient adherence is greater • C. There is less daily medication dosing • D. Multidrug therapy treats the patient’s other medical conditions

24. Question Two • The generic names of all but one drug in the classification end in “pril” • A. Angiotensin II receptor antagonists • B. Diuretics • C. Angiotensin-converting enzyme inhibitors • D. Beta-adrenergic blocking agents

25. Question Three • The generic names of all drugs in the classification end in “sartan” • A. Angiotensin II receptor antagonists • B. Diuretics • C. Angiotensin-converting enzyme inhibitors • D. Beta-adrenergic blocking agents

26. Question Four • The class of antihypertensives that increases urine production by affecting the renin-angiotensin-aldosterone pathway is the: • A. calcium channel blockers • B. Adrenergic blockers • C. ACE inhibitors • D. Direct-acting vasodilators

27. Question Five • The class of antihypertensives that relax smooth muscles in the blood vessels to decrease peripheral resistance are the: • A. Angiotensin receptor blockers • B. Beta adrenergic blockers • C. ACE inhibitors • D. Direct acting vasodilators

28. Antianginal Drugs Chapter 24

29. Coronary Heart Disease Caused by a restriction in blood flow to the myocardium Myocardium does not receive nutrients or O2 from the blood flowing through the heart It receives nutrients and O2 from the R and L coronary arteries, which branch off to smaller vessels and circle the heart

31. Angina- what symptoms does the pt have? • Sharp pain the chest • Often moves to the L side of the neck and jaw and down the L arm • Usually preceded by physical exertion or emotional excitement • Why do these events cause these symptoms?

32. Classification of Angina Pectoris

33. Drugs to Treat Anginal Episodes • MONA • Morphine • Oxygen • Nitroglycerin • Aspirin • Always apply OXYGEN as soon as you can to decrease myocardial oxygen demand • Check BP • if normal give Nitro • If low give Morphine • Have them chew 4 baby ASA (324mg) • To get the thinnest blood through the coronary arteries

34. Nitrates –Two Classes • MOA: Main effect is vasodilation • Reduces cardiac workload • Reduces oxygen consumption • To get most oxygenated blood to coronary arteries • Drugs to treat angina include nitroglycerin, isosorbidedinitrate,and isosorbidemononitrate. • They are clasified as short and long acting. • NC: Always make sure the BP is checked before a nitrate is given and in between each dose. • If ordered, give nitro every 5min x 3dose and then call 911

35. Nirtrates: Two Classes -Short vs. Long Acting • Short acting nitrates: • USE: Taken sublingually or IV to quickly stop an acute anginal attack in progress • nitroglycerin (Nitrostat, Nitrobid, Nitro-Dur) • Long acting nitrates: • USE: taken orally or through a patch to decrease frequency and severity of anginal episodes (preventative) • isosorbidedinitrate (Isordil) • isosorbidemononitrate (Imdur, Ismo)

36. Side effects • Hypotension/orthostatic hypotension • Reflex tachycardia • Headache • Flushing of skin • For Long Acting Nitrates: Tolerance commonly occurs with the long acting nitrates when taken for extended periods of time • NC: Pts are instructed to remove patch for 6-12 hours/day, usually at night, to delay the onset of tolerance “nitro break”

37. Beta-Adrenergic Blocking Drugs • Decrease heart rate and force of contractions: • Decrease cardiac workload • Decrease oxygen consumption • Adverse effects: • Drowsiness • GI disturbances • Nausea and diarrhea • Hypotension

38. Calcium Channel Blockers • Relax arterial smooth muscle: • Arteriolar vasodilation • Reduction of blood pressure • Reduction of cardiac workload and oxygen consumption • Common adverse effects: • Flushing • Dizziness • Hypotension • Profile drugs: • Verapamil (Calan) • Amlodipine (Norvasc)

39. Preferred Therapy for Angina Pectoris

40. Myocardial Infarction (MI) The result of a sudden occlusion of a coronary artery Early diagnosis and treatment of MI increases chances of survival Primary cause is CAD Goals of pharmacologic treatment are: Restoring blood supply to myocardium as quickly as possible through use of thrombolytics Reducing myocardial oxygen demand with organic nitrates, beta blockers, or CCBs to prevent another MI

41. MI Thrombolytics dissolve the existing clots that are blocking the coronary arteries Will restore blood flow to myocardium most effective when administered from 20 minutes to 12 hours after the onset of MI symptoms Several other drugs may be administered to prevent reinfarction and reduce mortality Beta blockers Antiplatelets and anticoagulants ACE inhibitors Analgesics

42. Cerebrovascular accident (CVA) Types Thrombotic/Embolic (most common) Hemorrhagic Symptoms are the same, but treatment very different! Thrombolytics given for thrombotic stroke Should be given within 3 hours of the attack If presented with symptom older than 3hrs, heparin/coumadin initiated Usually surgery for hemorrhagic stroke

43. Question One • A nurse has an order to administer a dose of nitroglycerin ointment (Nitro-Bid) to a client. The nurse would avoid doing which of the following in preparing the medication for administration? • A. Applying the dose in an even layer • B. Washing off the previous application • C. Using the fingers to spread the ointment • D. Using the manufacturer’s applicator papers

44. Question 2 The patient should remove the transdermal nitroglycerin patch at night to: Prevent overdose Prevent adverse reactions Ensure the dosage is appropriate Delay development of tolerance

45. Question 3 The nurse is administering nitroglycerin to a client is who complaining of chest pain. What would the nurse identify as a common side effect of this medication? Pulse rate of 120 beats per minute Increase in systolic blood pressure Onset of nausea and vomiting Client complains of a headache

46. Question 4 The patient taking calcium channel blockers should use extreme caution when taking which of the following medications? Acetaminophen (Tylenol) Ibuprofen (Motrin) Digoxin (Lanoxin) Ranitidine (Zantac)

47. Question 5 The patient is complaining of a viselike pain in his chest that subsides with rest. The patient is likely experiencing: A stroke A myocardial infarction Angina A cerebral vascular accident

48. Treatment for Heart Failure Chapter 22

49. Chronic Heart Failure

50. Physiology The amount of blood received in the right side should equal the amount out through the left side Preload and afterload are 2 important factors What is preload? How about afterload?