Hypertension

Question 1

High Ceiling Loop Diuretics

Answer 1

Drug: Furosemide (Lasix)

Action: Inhibits Na and H2O reabsorption loop of Henle and increases urine formation.

As the bodys plasma volume decreases, aldosterone production increases, promoting sodium reabsorption and loss of K and H ions, thus decreasing B/P and cardiac output.

Side Effects:
-hypokalemia
-hyponatremia
-hypochloremia
-hypotension (loss of volume, relaxation of
smooth muscle)
-OTOTOXICITY esp with aminoglycosides
-hyperglycemia
-hyperuricemia
-Increase anti coagulation effects w/ anticoagulant
- If taken with NSAID, decreases effectiveness

Question 2

Thiazides (diuretic)

Answer 2

Drug: Hydrochlorothiazide

Action: Acts on distal convoluted tubule.

Use: decrease blood pressure

Side Effects:
hypokalemia
hyponatremia
hypochloremia
hypotension (loss of volume, relaxation of 
      smooth muscle)
hyperglycemia
hyperuricemia

• Don’t take with digoxin (increases digoxin toxicity)
• decreases effectiveness of anti diabetics

Question 3

Potassium sparing diuretic

Answer 3

Drug: Spironolactone

Action: Blocks aldosterone in distal nephron, causes potassium retention, and increases sodium excretion.

Side effects:
hyperkalemia

Drug interactions:

• Thiazide & loop diuretics (furosemide)
• Agents that raise potassium levels
• salicylates decrease diuretic effect

Question 4

Osmotic diuretics

Answer 4

Drug: Mannitol

Actions: given parenterally, acts on the proximal convoluted tubule.

Therapeutic uses:
Renal failure prophylaxis
Reduce intracranial pressure
Reduce intraocular pressure

Adverse effects:
Edema
Fluid
Electrolyte imbalance

Question 5

Nursing responsibilities for diuretics

Answer 5

Monitor BP
teach about orthostatic hypotension
take meds as directed
dont double missed dose
do not stop abruptly
monitor weight gain and peripheral edema

Question 6

Beta 1 adrenergic blockers

Answer 6

end in -olol

Drugs:
Metoprolol
Propranolol

Monitor BP and apical pulse

Side effects:
dizziness
lightheaded
anorexia
if diabetic, monitor glucose
DO NOT STOP ABRUPTLY, need to taper

Question 7

ARB (angiotensin II receptor blockers)

Answer 7

end in -artan

Drugs:
Losartan
Valartan

Action:
selectively bind angiotensin II receptors, blood vessels prevent vasoconstriction and in adrenal cortex it prevents the release of aldosterone.

Question 8

ACE inhibitors (angiotensin converting enzyme inhibitor)

Answer 8

end in -pril

Drugs:
Captopril
Enalapril
Lisinopril

Action:
drug that blocks ACE, the enzyme responsible for converting angiotensin I to angiotensin II in the lungs; this blocking prevents the vasoconstriction and aldosterone release related to angiotensin II. Decreases preload and afterload.

Side effects:

• orthostatic hypotension
• unrelenting cough
• angioedema
• hyperkalemia

Question 9

Calcium Channel blockers

Answer 9

Amlodipine
Ditalizem
Verapamil

MOA: Inhibits calcium movement into coronary and vascular smooth muscle cells by blocking calcium channels cell membranes thus decreasing myocardial oxygen demand.

Contraindicated in asthma.

Interacts with digoxin= digoxin toxicity

Question 10

Vasodilators

Answer 10

Drugs: Nitroglycerin, Nitroprusside

General Action:
exert direct action on arteries and veins by decreasing peripheral vascular resistance by relaxing smooth muscle.

Nitroglycerine:
given sublingual, for angina
0.4 mg repeated every 5 minutes for 3 doses

Action: dilates all blood vessels but primarily venous circulation (coronary arteries)

Things to remember:

• potent
• decomposes in light, must be wrapped in foil or -in a brow bottle
• good for 24 hours
• cyanide toxicity (dyspnea, headache, vomiting, -dizziness, ataxia, loss of consciousness, imperceptible pulse, absent reflexes, dilated pupils, pink color, distant heart sounds, and shallow breathing)
• discard drugs in red or blue bags

Question 11

Lanoxin/Digoxin

Answer 11

A cardiac glycoside

Overall, this drug increases cardiac output/decrease myocardial workload to relieve symptoms of heart failure. Also treats AFIB, atrial flutter, and paroxysmal atrial tachycardia. It slows the heart rate

Digoxin increases intracellular calcium and allows more calcium to enter myocardial cells during depolarization , causing the following effects:

• increases myocardial contraction.
• increased C/O and renal perfusion
• slowed heart rate
• decreased conduction in AV node.

This drug has a very narrow margin of safety, be careful! Also is excreted, unchanged, in the urine, so monitor renal function and renal impairment. If impairment exists, can accumulate and cause toxicity.

Contraindications:
Grapefruit juice
antacids
lasix/furosemide
St. John’s wort
Ginseng, Hawthorne, licorice 

Teachings:
daily weight
BP <60 hold meds
monitor toxic effects

Adverse effects:

• Bradycardia
• anorexia
• arrhythmia a

Antagonist:
Digoxin immune fab (ovine, digibind)

Question 12

Phenytoin (anti epileptic)

Answer 12

The hydantoins stabilize nerve membranes throughout the CNS directly by influencing ionic channels in the cell membrane, thereby decreasing excitability and hyperexcitability to stimulation. By decreasing conduction through nerve pathways, they reduce the tonic–clonic, muscular, and emotional responses to stimulation. BASICALLY it reduces voltage frequency and spread of electrical charges.

May cause gingival hyperplasia, steven johnson syndrome, photosensitivity, hepatotoxicity, decreased folic acid, birth defects. May decrease effectiveness of oral contraceptives, you must monitor folic acid.

Take on an empty stomach. If taken IV, you can only use normal saline. Administer slowly to prevent cardiovascular arrest. Stop tube feeding 1 hour before and after.