Chapter 32 and 33: Diuretics

Question 1

what is a major organ in excretion and homeostasis?

Answer 1

-kidneys
-homeostasis:fluid balance (diuretic = decreased blood pressure and increased heart rate) , electrolyte balance, acid base balance (potassium/hydrogen)
-endocrine functions of the kidney: renin(secreted in response to low BP or sodium), erythropioetin, calcitrol

Question 2

when is diuretic therapy good for?

Answer 2

-edema
-pulmonary edema
-HTN
-HF
-renal failure
-liver failure or cirrhosis (scarring of the liver)

Question 3

what are common adverse effects of diuretic therapy?

Answer 3

-electrolyte imbalance (esp k)
-dehydration: kidneys need to be wet, and blood pressure determines how much blood is getting to the kidneys (how wet they are)
-hypotension: monitor BP and HR

Question 4

what are loop (high ceiling) diuretics?

Answer 4

-they’re the most effective types of diuretics
-they block sodium reabsorption in the loop of henle
-oral or parental
-bind extensively to plasma proteins (the bound part acts like a reservoir releasing the drug over time)
-indications: edema (fluid retention)

Question 5

what is the prototype drug for loop (high ceiling) diuretics?

Answer 5

-furosemide (lasix)
-therapeutic use: acute edema, HTN
-action: blocks sodium/potassium/chloride sympoter in loop of henle preventing reabsorption
-adverse effects: hyovolemia, orthostatic hypotension, fainting, tachycardia,dysrrhytmias,n/v, ototoxicity
-be cautious with pt with known sulfonamide allergy (some diuretics like furosemide are sulfonamide derivatives)

Question 6

what are drug interactions with loop diuretics?

Answer 6

-loop diuretics= hypokalemia, and if used with digoxin (if potassium levels are already really low=digoxin toxicity) = arrythmias (low potassium + digoxin toxity = big risk for arrhythmia)
-corticosteroids + lasix + amphotreicin b = potassium loss
-decreased elimination of lithium
-decreased diuretic effect with NSAIDS

Question 7

what are nursing considerations for loop (high ceiling) diuretics?

Answer 7

-complete health history
-monitor VS (apical HR,rhythm, BP)
-establish safety precautions
-observe older adults carefully
-ensure ready access to bathroom
-administer early in the day
-watch potassium levels

Question 8

what are drugs similar to lasix?

Answer 8

-bumex: used for ascites, peripheral edema
-edecrin: can be used for pts allergic to sulfonamides, but causes most severe hearing loss

Question 9

what are thiazide diuretics?

Answer 9

-most commonly prescribed diuretics
-blocks sodium reabsorption, by inhibiting the sodium/chloride symporter at the early distal tube, causing more diuresis
-available only in po except chlorothiazide
-adverse effects similar to loop diuretics but no ototoxicity
-indications: edema, HTN

Question 10

what is the prototype drug for thiazide diuretics?

Answer 10

-hydrochlorothiazide (HCTZ)
-therapuetic effects: edema, HTN, HF

Question 11

what are the adverse and serious effects of HCTZ

Answer 11

-adverse: hypotension, headache, dizziness, electrolyte imbalance, dysrrthymias, gout attacks
-serious: blood dyscrasis (abnormal conditions of the blood, bone marrow or lymph tissue)

Question 12

what are contra/precautions for HCTZ?

Answer 12

-anuria
-prior sensitivity to thiazide diuretics or sulfonamides antibiotics
-diabetes (worry about the eyes, heart, kidneys, feet)
-hypovolemia, hypotension

Question 13

what are considerations for thiazide diuretics?

Answer 13

-get baseline and periodic serum electrolyte values
-caution with electrolyte drinks
-encourage water intake instead of alcohol or caffeinated drinks
-ensure ready access to bathroom
-measure BP before therapy and at regular intervals
-monitor I&O
-monitor for therapeutic effectiveness and adverse effects

Question 14

what is the txt of overdose for loop, thiazine, potassium sparing diuretics?

Answer 14

-loop: supportive meaures, replace fluids and electrolytes, possible administration of vasopressors
-thiazine: infusions of fluids with electrolytes
-potassium; therapies to counteract hyperkalemia, administer cationic exchange resin

Question 15

what are potassium-sparing diuretics?

Answer 15

-less effective than the other 2 types of diuretics but can prevent hypokalemia
-action: two types (sodium channel inhibitors of aldosterone antagonist)
-sodium channel inhibitors: block sodium channels in the distal tube that are suppose to be reabsorbing sodium , so only sodium is excreted not potassium
-aldosterone antagonist: inhibit aldosterone = decreased sodium reabsorption, and increase sodium, chloride, and water excretion

Question 16

what is the prototype drug for potassium sparing diuretics?

Answer 16

-spironolactone (aldactone) which is an aldosterone antagonist
-inhibits action of aldosterone in distal tubes and collecting ducts c
-therapeutic effects: mild HTN
-action:Inhibits action of aldosterone in distal tubule and collecting ducts of nephron
Sodium, chloride, and water excretion are increased.
Body retains potassium.
-do not give with ACE inhibitors as both increase potassium levels = may cause arrhytmias

Question 17

what are adverse and serious effects of aldactone?

Answer 17

-adverse:muscle weakness, flaccid paralysis, parasthesia, bradycardia,fatigue,shock, decreaesd fertility
-serious:life threathening cardiac dysrrhytmias

Question 18

what are drug interactions for potassium sparing diuretics?

Answer 18

-acidosis with ammonium chloride
-decreased diuretic affects with salicytes
-decreases effects of digoxin (which is used to improve strength and contractability of the heart)
-if taken with potassium supplements, ACE (angiotensin converting enzyme) inhibitors, or ARB (Angiotensin II Receptor Blocker) can cause hyperkalemia
-ACE causes the sodium reabsorption and loss of potassium, but ace inhibitors casue potassium reabsorption and sodium excretion
-if the ACE inhibitors irritate the pt, put them on ARB