ppt chapter 51-1

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Diuretic AgentsDiuretic Agents

Chapter 51


Classes of DiureticsClasses of Diuretics

• Thiazide and Thiazide-like Diuretics

• Loop Diuretics

• Carbonic Anhydrase Inhibitors

• Potassium-Sparing Diuretics

• Osmotic Diuretics


Function of Diuretic AgentsFunction of Diuretic Agents

• Increase the amount of urine produced by the kidneys

• Increase sodium excretion


Indications for Diuretic UseIndications for Diuretic Use

• Edema associated with congestive heart failure

• Acute pulmonary edema

• Liver disease (including cirrhosis)

• Renal disease

• Hypertension

• Conditions that cause hyperkalemia


Sites of Action of Diuretics Sites of Action of Diuretics


Thiazide and Thiazide-Like DiureticsThiazide and Thiazide-Like Diuretics

• Hydrochlorothiazide (HydroDIURIL)

• Chlorothiazide (Diuril)

• Bendroflumethiazide (Naturetin)

• Benzthiazide (Exna)

• Hydroflumethiazide (Diucardin)

• Methyclothiazide (Aquatensen)

• Polythiazide (Renese)

• Trichlormethiazide (Diurese)


Thiazide and Thiazide-Like Diuretics (cont.)


• Actions

– Action is to block the chloride pump

– Keeps chloride and the sodium in the tubule to be excreted in the urine, thus preventing the reabsorption of both in the vascular system

• Indications

– Treatment of edema associated with CHF, liver, or renal disease

– Monotherapy or adjuncts for the treatment of hypertension




• Pharmacokinetics

– Well absorbed for the GI tract, metabolized in the liver and excreted in the urine.

• Contraindications

– Allergy to thiazides or sulfonamides

– Fluid and electrolyte imbalances, and renal and liver disease

– Bipolar disorders

– Pregnancy and lactation




• Caution

– Gout

– Systemic lupus

– Diabetes

– Hyperparathyroidism

• Adverse Effects

– Related to interference with the normal regulatory mechanisms of the nephron

– Hypokalemia

– Lithium




• Adverse Effects (cont.)

– Decreased calcium excretion

– Altered blood glucose levels

– Urine will be slightly alkalinized

• Drug-to-Drug Interactions

– Cholestyramine or colestipol

– Digoxin

– Antidiabetic agents


QuestionQuestion

What is the action of thiazide diuretics?

A. Blocks the chloride pump

B. Blocks the sodium pump

C. Blocks the potassium pump

D. Blocks the carbonic anhydrase pump


AnswerAnswer

A. Blocks the chloride pump

Rationale: Thiazide and thiazide-like diuretics act to block the chloride pump. Chloride is actively pumped out of the tubule by cells lining the ascending limb of the loop of Henle and the distal tubule.


Loop DiureticsLoop Diuretics

• Furosemide (Lasix)

– Most commonly used; less powerful than new drugs; larger margin of safety for home use

• Bumetanide (Bumex) and Torsemide (Demadex)

– New drugs; more powerful than Lasix

• Ethacrynic acid (Edecrin)

– First loop diuretic introduced, used less frequently in the clinical setting


Loop Diuretics (cont.)Loop Diuretics (cont.)• Actions

– Block the chloride pump in the ascending loop of Henle

– This causes reabsorption of sodium and chloride

• Indications

– Acute CHF

– Acute pulmonary edema

– Edema associated with CHF

– Edema associated with renal or liver disease

– Hypertension


Loop Diuretics (cont.)Loop Diuretics (cont.)


– Metabolized and excreted primarily through the urine


– Allergy

– Electrolyte depletion

– Anuria

– Severe renal failure

– Hepatic coma




• Caution

– SLE, gout, and diabetes mellitus

• Adverse Effects

– Related to the imbalance in electrolytes and fluid

– Hypokalemia

– Alkalosis

– Hypocalcemia




– Aminoglycosides or cisplatine

– Anticoagulation

– Indomethacin, ibuprofen, salicylates, or NSAIDs


Carbonic Anhydrase InhibitorsCarbonic Anhydrase Inhibitors

• Actions

– Block the effects of carbonic anhydrase; slow down the movement of hydrogen ions

– More sodium and bicarbonate are lost in the urine

• Indications

– Adjuncts to other diuretics

– Glaucoma


Carbonic Anhydrase Inhibitors (cont.)Carbonic Anhydrase Inhibitors (cont.)


– Rapidly absorbed and widely distributed

– Excreted in the urine


– Allergy

– Angle closure glaucoma



• Caution

– Lactation

– Fluid or electrolyte imbalances

– Renal or hepatic disease

– Adrenocortical insufficiency

– Respiratory acidosis

– COPD



• Adverse Effects

– Related to disturbances in acid and base balance and electrolyte balances

– Metabolic acidosis

– Hypokalemia

– Paresthesias of extremities, confusion, drowsiness


– Salicylates and lithium


QuestionQuestion

Please answer the following statement as true or false.

The loop diuretics cause the body to excrete a copious amount of potassium-rich urine.


AnswerAnswer

False

Rationale: The loop diuretics have a similar effect in the descending loop of Henle and in the distal convoluted

tubule, resulting in the production of a copious amount of sodium-rich urine.


Potassium-Sparing DiureticsPotassium-Sparing Diuretics

• Actions

– Cause a loss of sodium while retaining potassium

– Block the actions of aldosterone in the distal tubule

• Indications

– Adjuncts with thiazide or loop diuretics

– Patients who are at risk for hypokalemia


– Well absorbed, protein bound, and widely distributed

– Metabolized in the liver and excreted in the urine


Potassium-Sparing Diuretics (cont.)Potassium-Sparing Diuretics (cont.)


– Allergy

– Hyperkalemia, renal disease, or anuria

– Patients taking amiloride or triamterene

• Caution


• Adverse Effects

– Hyperkalemia


– Salicylates


Osmotic DiureticsOsmotic Diuretics• Actions

– Pull water into the renal tubule without sodium loss

• Indications

– Increased cranial pressure or acute renal failure due to shock, drug overdose, or trauma


– Freely filtered at the renal glomerulus, poorly reabsorbed by the renal tubule

– Not secreted by the tubule

– Resistant to metabolism


Osmotic Diuretics (cont.)Osmotic Diuretics (cont.)


– Renal disease and anuria

– Pulmonary congestion

– Intracranial bleeding, dehydration

– CHF

• Adverse Effects

– Related to sudden drop in fluid levels

– Nausea, vomiting, hypotension, light-headedness, confusion, and headache


Use of Diuretic Agents Across the Lifespan

Use of Diuretic Agents Across the Lifespan


Prototype Thiazide and Thiazide-Like Diuretics

Prototype Thiazide and Thiazide-Like Diuretics


Prototype Loop DiureticsPrototype Loop Diuretics


Prototype Carbonic Anhydrase InhibitorsPrototype Carbonic Anhydrase Inhibitors


Prototype Potassium-Sparing DiureticsPrototype Potassium-Sparing Diuretics


Prototype Osmotic Diuretics Prototype Osmotic Diuretics


Prototype Osmotic Diuretics (Continued) Prototype Osmotic Diuretics (Continued)


QuestionQuestion

How do carbonic anhydrase inhibitors work?

A. Slow down the reabsorption of sodium

B. Speeds up creation of sodium bicarbonate

C. Balances acidic and alkaline solutes in urine

D. Slows down the movement of hydrogen ions


AnswerAnswer

D. Slows down the movement of hydrogen ions

Rationale: Diuretics that block the effects of carbonic anhydrase slow down the movement of hydrogen ions. As a result, more sodium and bicarbonate are lost in the urine.


Nursing Considerations for Thiazide and Thiazide-Like Diuretics

Nursing Considerations for Thiazide and Thiazide-Like Diuretics

• Assessment: History and Physical Exam

• Nursing Diagnosis

• Implementation

• Evaluation


Nursing Considerations for Loop DiureticsNursing Considerations for Loop Diuretics



• Implementation

• Evaluation


Nursing Considerations for Carbonic Anhydrase Inhibitors

Nursing Considerations for Carbonic Anhydrase Inhibitors



• Implementation

• Evaluation


Nursing Considerations for Potassium-Sparing Diuretics

Nursing Considerations for Potassium-Sparing Diuretics



• Implementation

• Evaluation


Nursing Considerations for Osmotic Diuretics

Nursing Considerations for Osmotic Diuretics



• Implementation

• Evaluation

ppt chapter 51-1

Documents

action of thiazide diuretics

classes of diuretics

diuretics act

chloride pumprationale

chloride pumpb

blockthe chloride pump

diuretic use edema

loop ofhenle