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| 1. According to the JNC 7 guidelines, what are the drug(s) of choice for a patient with uncomplicated hypertension? |
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Definition
| 1. The drugs of choice for those patients with uncomplicated hypertension are diuretics. BB have been considered first line with JNC7 but this may change with the new guidelines. Typically, BB are indicated if pt is s/p MI. |
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| 2. What is the action of the ACE inhibitors and what does this cause? |
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Definition
1. ACE inhibitors inhibit the angiotensin converting enzyme. This does not allow angiotensin I to form into angiotensin II. Since angiotensin II is a potent vasoconstrictor, vasodilation occurs. Also the decrease in angiotensin II causes a decrease in aldosterone synthesis which in turn decreases sodium and water retention, decreasing blood pressure
2. Also the ACE inhibitors have action against Kininase II. This enzyme degrades bradykinin-a vasodilator. If the enzyme is blocked there is more bradykinin available to contribute to vasodilation. |
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| 3. How do the angiotensin II receptor antagonists work? How do they differ from the ACE inhibitors? |
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Definition
1. Angiotensin II receptor antagonists exert their effect on the receptor itself. The do not allow angiotensin II to bind to the receptor, decreasing its effect.
2. They differ from ACE inhibitors in that they work on the receptor itself and also do not have activity related to bradykinin. This decreases the occurrence of cough and angioedema. |
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| 4. What are the differences in the selective and non selective beta blockers? |
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Definition
| 1. The selective beta blockers have somewhat less side effects. They primarily exert their effect on beta 1 receptors. They can be used with caution in pts with respiratory conditions. The nonselective beta blockers have action against beta 2 receptors causing, in some patients, respiratory side effects. They also cause more hyperglycemia than the selective beta blockers. |
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Term
| 5. How do the subcategories of the calcium channel blockers differ? |
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Definition
1. Calcium channel blockers are broken down into two categories, the non-dihydropyridines and the dihydropyridines.
1. Non-dihydropyridines are further categorized into the diphenylalkylamine based and the benzothiazepine based.
1. These decrease the rate of recovery of calcium channels causing depression of the SA node firing and slowing AV node conduction. They have more of an effect on heart rate than the dihydropyridines. Not used in the control of BP as much as for tachy arrhythmias.
2. Dihydropyridines-do not affect the rate of recovery of the calcium channels. They act more on the periphery. Do not affect AV node conduction therefore have less effect on decreasing heart rate. They have a greater affinity for vascular calcium channels causing more vasodilation. Because of this, more peripheral edema is seen with this category. |
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| 6. Where are the alpha 1 receptors and what are are their actions? How do the peripheral alpha 1 adrenergic antagonists work? |
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Definition
| 1. Alpha 1 receptors are located in the eye, salivary glands, arterioles, post capillary venules, GI and GU sphincters. They are associated with excitation or stimulation (constriction). Peripheral alpha 1 adrenergic antagonists block alpha 1 receptors resulting in relaxation of all alpha 1 receptors. This causes vasodilation in post capillary venules, decreasing peripheral vascular resistance, causing decreased BP. However they are not very selective so they also cause vasodilation in all the other areas listed above. They do have a great deal of side effects because of this. Due to the relaxation of the GU sphincter, they are indicated in BPH. |
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| 7. What are the actions of the alpha 2 receptors? How do the alpha 2 agonists work? |
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Definition
1. The alpha 2 receptors are located in the nerve terminals of smooth muscles. They are associated with relaxation and inhibition.
2. The alpha 2 agonists act on the central alpha 2 receptors. This results in inhibition of cardiac acceleration and vasoconstriction centers in the brain. This causes decreased peripheral resistance, decreased renal vascular resistance, heart rate and BP. |
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| 8. Which electrolyte is most affected by the administration of Lasix? |
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Definition
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| 9. Which of the diuretics is potassium sparing? |
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Definition
2. Selective aldosterone receptor antagonists
These medications inhibit action of aldosterone which results in the inhibition sodium and water retention.
Have no activity if aldosterone is absent as in Addison’s disease.
The difference between the two classes above is the second is more specific to the receptors and does not cause the hormonal effects (gynecomastia, menstrual irregularities) that the first class does. |
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| 10. Which medication is used for acute abortive therapy in the treatment of chest pain? |
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Definition
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| 11. What is the goal of therapy when treating chest pain with nitrates? Because of this, what are the adverse effects? |
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Definition
To reduce preload, afterload and lower cardiac oxygen demand.
Adverse effects are headache, dizziness, hypotension, weakness. Can also cause reflex tachycardia. |
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| 12. What is the mechanism of action of digoxin? |
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Definition
| It inhibits the Na-K-ATPase membrane pump. This leads to an increase in intracellular sodium concentration and an increase in intracellular calcium-this causes an increase in the force of contraction of the heart. |
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