1. Drugs for Hypertension17
Drugs for Hypertension

2. Directory
Classroom Response System
Lecture Note Presentation

3. Question 1
Which of the following is not a nonpharmacologic method of controlling hypertension?

4. Question 1 Choices Weight loss Smoking cessation Moderate exercise
Decreased potassium and magnesium intake

5. Question 1 Answer Weight loss Smoking cessation Moderate exercise
Decreased potassium and magnesium intake

6. Question 2
An otherwise healthy man has been diagnosed with hypertension. You suspect that the physician will order:

7. Question 2 Choices Hydrochlorothiazide (Microzide) Captopril (Capoten)
Nifedipine (Adalat, Procardia)
Enalapril (Vasotec)

8. Question 2 Answer Hydrochlorothiazide (Microzide) Captopril (Capoten)
Nifedipine (Adalat, Procardia)
Enalapril (Vasotec)

9. Question 3
The patient is on two antihypertensive drugs. The nurse recognizes that the advantage of multidrug treatment is:

10. Question 3 Choices Blood pressure decreases faster.
Adverse effects are fewer and patient adherence is greater.
There is less daily medication dosing.
Multidrug therapy treats the patient’s other medical conditions.

11. Question 3 Answer Blood pressure decreases faster.
Adverse effects are fewer and patient adherence is greater.
There is less daily medication dosing.
Multidrug therapy treats the patient’s other medical conditions.

12. Question 4
The patient is taking furosemide (Lasix) 40 mg bid. The patient should be monitored for:

13. Question 4 Choices Hyperkalemia Hypokalemia Hypernatremia
Hypercalcemia

14. Question 4 Answer
Hyperkalemia
Hypokalemia
Hypernatremia
Hypercalcemia

15. Learning Outcomes Explain how hypertension is defined.
Summarize the long-term consequences of untreated hypertension.
Describe how the pumping action of the heart creates blood pressure.
Explain the effects of cardiac output, peripheral resistance, and blood volume on blood pressure.

16. Learning Outcomes
Discuss how the vasomotor center, baroreceptors, emotions, and hormones influence blood pressure.
Discuss the role of therapeutic lifestyle changes in the management of hypertension.
Describe general principles guiding the pharmacotherapy of hypertension.

17. Learning Outcomes
For each of the classes listed in the Drug Snapshot, identify representative medications and explain the mechanism of drug action, primary actions, and important adverse effects.

18. Core Concept 17.1
Hypertension is defined as the consistent elevation of arterial blood pressure.

19. Hypertension Consistent elevation of arterial blood pressure
Rarely made on a single blood pressure measurement
Diagnosis made:
Sustained systolic blood pressure of greater than 140 mm Hg

20. Hypertension
Or diastolic pressure of greater than mm Hg after multiple measurements are made over several clinic visits.

23. Core Concept 17.2
Failure to treat hypertension can lead to stroke, heart failure or myocardial infarction.

24. Hypertension Primary/Essential No specific cause Risk Factors
Advancing age
Weight gain, particularly around the hips & thighs

25. Hypertension Primary/Essential Blacks Men Hereditary component,
Tobacco use
High-fat diets

26. Secondary Hypertension
Certain diseases
Cushing’s syndrome
Hyperthyroidism
Chronic renal disease

27. Secondary Hypertension
Certain drugs
Corticosteroids
Oral contraceptives
Erythropoietin (epoetin alfa)
Therapeutic goal
Treat or remove the underlying condition

28. Blood pressure is caused by the pumping action of the heart.
Core Concept 17.3
Blood pressure is caused by the pumping action of the heart.

29. Pumping Action of the Heart
Pressure can be measured in nearly any vessel in the body
Commonly refers to the pressure in the arteries.¥
Pumping action of the heart is the source of blood pressure

30. Pumping Action of the Heart
Arteries closest to the heart, such as the aorta, have the highest pressure.
Pressure decreases gradually as the blood travels farther from the heart, until it falls close to zero in the largest veins

31. Figure 17.1 Blood pressure changes throughout the circulation

32. Blood Pressure Systolic pressure Diastolic pressure
The ventricles of the heart contract and eject blood
Diastolic pressure
The ventricles relax
The heart temporarily stops ejecting
Blood pressure in the arteries will fall

33. Blood Pressure
Measured in units of millimeters mercury, abbreviated as mm Hg.

34. Figure (a) Systolic pressure occurs when the heart ejects blood, creating high pressure in the arteries. (b) Diastolic pressure occurs when the heart relaxes, resulting in less pressure in the arteries.

35. Core Concept 17.4
The primary factors responsible for blood pressure are cardiac output, the resistance of the small arteries, and blood volume.

36. Cardiac Output The volume of blood pumped per minute
Resting cardiac output is approximately 5 liters per minute (L/min)
Strenuous exercise can increase this output to as much as 35 L/min

37. Cardiac Output
Drugs that change the cardiac output have the potential to influence a patient’s blood pressure
higher the cardiac output, the higher the blood pressure.

38. Peripheral Resistance
Blood flows at high speeds through the vascular system
Bumps and drags across the walls of the vessels
Friction reduces the velocity of the blood

39. Blood Volume Total amount of blood in the vascular system
Average person maintains a relatively constant blood volume of approximately 5 L
Change with

40. Blood Volume Certain regulatory factors Certain disease states
More blood in the vascular system will exert additional pressure on the walls of the arteries and raise blood pressure.

41. Figure 17.3 Primary factors affecting blood pressure

42. Core Concept 17.5
Many nervous and hormonal factors help to keep blood pressure within normal limits.

43. Figure 17.4 Blood pressure is controlled by the actions of the cardiovascular system and kidneys.

44. Figure 17.5 Hormonal and nervous factors influencing blood pressure

45. Concept Review 17.1
Because hypertension may cause no symptoms, how would you convince a patient to take his or her medication regularly?

46. Core Concept 17.6
Positive lifestyle changes can reduce blood pressure and lessen the need for medications.

47. Life Style Changes
Implement a medically supervised, safe weight-reduction plan, if 20% or more over normal body weight.
Stop using tobacco.
Restrict salt (sodium) intake, and eat foods rich in potassium and magnesium.

48. Life Style Changes Limit alcohol consumption.
Implement a medically supervised aerobic exercise plan.
Reduce sources of stress and learn to implement coping strategies.

49. Core Concept 17.7
Selection of specific antihypertension drugs depends on the severity of the disease.

50. Goal of Therapy
The goal of antihypertensive therapy is to reduce blood pressure to normal levels so that the long-term consequences of hypertension may be prevented

51. Figure 17.6 Mechanism of action of antihypertensive drugs

52. Primary Antihypertensive Agents
Diuretics
Renin-angiotensin-aldosterone inhibitors
Calcium channel blockers (CCBs)
Beta-adrenergic blockers

53. Core Concept 17.8
Diuretics are often drugs of first choice for treating mild to moderate hypertension.

54. Actions of Diuretic
Increase the amount of urine produced by the kidneys. Widely used in the treatment of hypertension and heart failure.
Reduce blood volume through the urinary excretion of water and electrolytes
Mechanisms of actions differ

55. Electrolyte Imbalance
Loss of potassium, sodium, and magnesium
Loss of potassium, or hypokalemia
Can lead to serious abnormalities in cardiac rhythm
Thiazide or loop diuretics

57. Concept Review 17.2
State the major reasons why patients should continue lifestyle changes even though their antihypertensive drugs appear to be effective.

58. Core Concept 17.9
Calcium channel blockers have emerged as important drugs in the treatment of hypertension.

59. Calcium Channel Blockers
Group of about 10 drugs
Used to treat a number of cardiovascular diseases
Angina pectoris
Cardiac dysrhythmias
HTN.

60. Mechanism of Action
Contraction of a muscle regulated by amount of calcium ion inside muscle cell
Contraction occurs when calcium enters the cell through channels in the plasma membrane

61. Mechanism of Action
CCBs block these channels prevent Ca+2 from entering the cell
Inhibits muscular contraction
At low doses cause vasodilation in arterioles
Decreases blood pressure

62. Mechanism of Action
Some CCBs are selective for calcium channels in arterioles
Others affect channels in both arterioles and cardiac mus

64. Core Concept 17.10
Blocking the renin-angiotensin-aldosterone system leads to a decrease in blood pressure.

65. Renin-Angiotensin-Aldosterone System (RAAS)
One of the primary homeostatic mechanisms controlling blood pressure and fluid balance in the body
Drugs that modify the RAAS decrease blood pressure and increase urine volume.
Block angiotensin II, thus decreasing blood pressure through two mechanisms: dilating arteries and decreasing blood volume.

67. Table 17.5 (continued) ACE Inhibitors and Angiotensin-Receptor Blockers Used for Hypertension

68. Core Concept 17.11
Alpha- and beta-adrenergic blockers are commonly used to treat hypertension.

69. Alpha and Beta Blockers
Blocking the sympathetic “fight or flight” responses
Drugs can cause the heart rate to slow, blood pressure to decline and the bronchi to dilate

70. Alpha and Beta Blockers
Actions
Blockade of alpha1 receptors in the arterioles
Blockade of beta1 receptors in the heart
Nonselective blockade of both beta1 and beta2 receptors
Stimulation of alpha2-adrenergic receptors in the brainstem (centrally acting)

72. Table 17.6 (continued) Adrenergic Blockers and Central-Acting Agents Used for Hypertension

73. Concept Review 17.3
Why is it important for the patient to weigh himself or herself on a regular basis when taking antihypertensive drugs?

74. Core Concept 17.12
Vasodilators lower blood pressure by relaxing arteriolar smooth muscle.

75. Vasodilators
Affect vascular smooth muscle highly effective at lowering blood pressure
Not drug of first choice
Many adverse effects
Direct vasodilators produce reflex tachycardia
Normal physiological response to sudden decrease in blood pressure

76. Vasodilators
Forces the heart to work harder, blood pressure increases, counteracting the effect
Sodium and water retention
Kidney retains more sodium and water, blood volume increases, raises blood pressure