Diuretics

Question 1

Types of Diuretics:

Answer 1

• Loop Diuretics
• Thiazide
• Osmotic Diuretics
• Potassium Sparing Diuretics

Question 2

Normal urine output is considered to be __ ml/hour or greater

Answer 2

30 ml/hr

Question 3

Loop Diuretics include:

Answer 3

• Furosemide (Lasix)
• Bumetanide
• Ethacrynic acid
• Torsemide

Question 4

Thiazides include:

Answer 4

Hydrocholorothiazide

Question 5

Osmotic include:

Answer 5

Mannitol

Question 6

Potassium Sparing include:

Answer 6

Spironolactone

Question 7

Diuretics: LOOP

Furosemide (Lasix)

Answer 7

-Indications:
Very powerful diuretic given for massive movement of fluids, usually in both acute and chronic heart failure; if a lesser diuretic such as a thiazide can be used, it is generally best to do so.

-MOA:
Rapid acting loop diuretic, inhibits Na and Cl reabsorption in ASCENDING LOOP OF HENLE

-Therapeutic Action:
Decreases edema, decreases BP

-Adverse Effects:
postural hypotension, loss of K, Na, Mg, Cl; HYPOKALEMIA, HYPONATREMIA, HYPOCHLOREMIA, Nausea and vomiting, dehydration; tinnitus, aplastic anemia; circulatory collapse

Question 8

Furosemide (Continued…)

Answer 8

-Nursing Implications:

check K level before giving(3.5- 5.0); check BP before giving (>110/60); Weigh daily to evaluate its effectiveness; rapid IV use has caused cardiac arrest; monitor pts closely during high volume diuresis for hypotension, circulatory collapse.

-Dosage:

Oral, IV, IM, 20 mg- 80 mg; IV action starts in 5 minutes and lasts for 2 hours.

Question 9

Furosemide Drug Interactions:

Answer 9

• If low potassium, high risk for DIG TOXICITY
• Digoxin toxicity causes many different drug dysrhythmias
• Hearing loss when combined with other ototoxic drugs such as aminoglycosides
• Lithium - causes high sodium levels
• Hypotension when combined with any other antiyhypertensive

Question 10

Hydrochlorothiazide (Hydrodiuril)

Answer 10

-MOA:
Blocks reabsorption of Na and Cl in early segment of the distal convoluted tubule. Drug not effective if there is low GFR < 15-20 ml/min

-Indication:
Hypertension, frequently 1st choice drug especially in African Americans. Can also be used in mild to moderate heart failure, mobilize edema associated with hepatic or renal disease

-Dosage:
Given orally, dosage depends on formulation

Question 11

Hydrochlorothiazide (Hydrodiuril) Cont…

Answer 11

-Adverse Effects:
Hyponatremia, hypochloremia, dehydration, hypokalemia; can cross placental barrier causing severe harm and is CONTRAINDICATED DURING PREGNANCY. Also can enter breast milk; elevate glucose levels in diabetes; May precipitate gouty arthritis

-Drug Interactions:
Promote digoxin toxicity due to promoting potassium loss; Increase effects of hypotension when combined with other anti-hypertensives.

• Can elevate glucose levels in diabetes!
• Can elevate uric acid levels
• Give in conjunction with furosemide

Question 12

Mannitol (Osmitrol)

MOST EFFICACIOUS DIURETIC
Rarely used in HF patients

Answer 12

-Osmotic diuretic (only one at this time in USA)

-MOA:
In the proximal convoluted tubule, mannitol creates osmotic action that inhibits passive reabsorption of water. No significant effect on excretion of K

-Indications:
Can prevent or slow onset of renal failure in severe hypotension, hypovolemic shock; Reduction of ICP, caused by cerebral edema; reduction of intraocular pressure in cases not responding to usual therapy.

Question 13

Mannitol (Osmitrol) cont…

Answer 13

-Adverse Effects:
Headache, N&V, Electrolyte imbalance possible, pulmonary edema and congestive heart failure edema.

-Administration:
Solutions are 5-25% and usually crystallized; warm in water; Administer per IV infusion to obtain urine flow rate of 30-50ml. (ONLY GIVEN IV)

Question 14

Potassium Sparing Diuretics:

Two Categories:

Answer 14

Aldosterone Antagonists:
-Spironolactone

Nonaldosterone Antagonist:

• Triamterine
• Amiloride

Question 15

Spironolactone (Aldactone)

Answer 15

-Classification:
Potassium Sparing Diuretic (Aldosterone Antagonists)

-MOA:
Blocks action of aldosterone in the distal nephron; Since aldosterone promotes Na uptake in exchange for K secretion, inhibition of aldosterone causes retention of K and excretion of Na.

-Indication:
Hypertension and mild edema; Usually given in combo with a Loop or thiazide diuretic because of low diuresis

Question 16

Spironolactone (Aldactone) Cont.

Answer 16

-Adverse Effects:
Hyperkalemia >5.0 (injection of insulin can reverse this) resulting in fatal cardiac dysrhythmias such as VFib. Endocrine effects such as gynecomastia and menstrual irregularities since the drug is similar in chemical structure to steroid hormones

-Nursing Implications:
NEVER give Aldactone in conjunction with potassium, salt substitutes, or another potassium sparing drug

Question 17

Don’t give substitute _______ with Spironolactone (Aldactone); WILL KILL PATIENT

Answer 17

potassium

Question 18

Triamterine (Dyrenium)

Answer 18

-Classification:
Non-Aldosterone Sparing Diuretic

-MOA:
Disrupts sodium-potassium exchange DIRECTLY in the distal nephron

-Indications:
Hypertension and edema (scant diuresis); used mainly to counteract the potassium wasting effects of lasix, etc.

-Adverse Effects:
Commonly N/V, leg cramps, dizziness; hyperkalemia, also use caution if combined with ACE inhibitors, ARBS, direct renin inhibitors

Question 19

Prototype: Potassium Chloride

potassium supplementation

Answer 19

-MOA:
Replacement

• Transmission of nerve impulses especially in the heart, hypo or hyperkalemia will both cause cardiac dysrhythmias
• Potassium is lost in vomiting, diarrhea, wound drainage, PROLONGED DIURESIS; diabetic ketoacidosis

-Oral:
Make sure to give large pills with water and with patient sitting up

-Liquid KCl:
Dilute in orange juice according to directions

Question 20

Potassium Chloride NURSING IMPLICATIONS:

Answer 20

• IV, can only be given per IV drip
• NEVER push and no faster than 10 meq per hour****
• never add KCL to an existing IV;
• Dilute 10 meq in 100 ml (D5W); 40meq/500-1000mL;
• check K level before giving each dose (X3);
• Mix K well in the IV solution.

Question 21

Potassium Chloride Cont..

Answer 21

-Adverse Effects:
Oral KCl can irritate GI tract causing abdominal discomfort, N&V, diarrhea; large pills can cause SEVERE intestinal ulcers can resulting in bleeding and perforation.

• Hyperkalemia can cause cardiac dysrhythmias- (mild, 5-7: Prolonged PR, Tented t waves); (severe >7: cardiac arrest due to V-tach or V-Fib).
• FINAL WARNING: potassium given IV push OR more than 10 meq/hour will cause INSTANT DEATH!!!!!****

Question 22

Excess Potassium: Symptoms in addition to cardiac can include:

Answer 22

• Confusion
• Anxiety
• Dyspnea
• Heaviness or tingling of legs
• Numbness/tingling of hands, lips, feet

Question 23

Steps to Control/Remove Excess Potassium

1. Withhold potassium containing ____/___ including potassium sparing diuretics

Answer 23

Foods/meds

Question 24

2. Infuse _______ ________ to counteract cardiotoxicity

Answer 24

Calcium gluconate

Question 25

3. Infuse ______ and ______to push potassium intracellularly

Answer 25

insulin and glucose

Question 26

4. Infuse _______ __________ to increase pH and increase cellular intake of potassium

Answer 26

sodium bicarbonate

Question 27

5. Give either oral or by enema _______, an exchange resin that removes K (most common ways)

Answer 27

Kayexalate (sodium polyesterene sulfonate)

Question 28

6. Do ________ or ________ to remove potassium

Answer 28

peritoneal or hemodialysis