Karch Focus on Pharmacology Chapter 51- Diuretic Agents
A patient with a longstanding diagnosis of chronic renal failure has experienced a significant decline in urine output in recent days, prompting him to seek care at a local clinic. A nurse at the clinic has suggested to a colleague that the administration of a diuretic such as hydrochlorothiazide may improve the patient's urine output. How should the colleague best respond to this suggestion?
"Actually, patients with renal failure usually can't take hydrochlorothiazide." Renal disease and severe renal impairment contraindicate the use of hydrochlorothiazide. HCTZ affects the kidneys, not the bladder, and is not administered intravenously.
After teaching a patient about the action of spironolactone, the nurse determines that the teaching was successful when the patient states: "I should take the medicine around dinnertime for the best effect." "I need to take the drug on an empty stomach." "I can still use my salt substitute if I want to." "I need to make sure I don't eat too many high potassium foods."
"I need to make sure I don't eat too many high potassium foods." The drug is a potassium sparing diuretic placing the patient at risk for hyperkalemia, especially if the patient consumes foods high in potassium. The patient should take the medication in the morning to prevent interfering with sleep by having to get up at night to void. The patient can take the drug with meals if GI upset occurs. Many salt substitutes contain potassium, which could increase the patient's risk for hyperkalemia.
A male client has been ordered spironolactone (Aldactone) for hypertension. Which statement by the client indicates a need for further education? "I will take the medication when my blood pressure is elevated." "I do not need to increase my potassium intake with this medication." "I may experience breast enlargement." "I will weigh myself daily."
"I will take the medication when my blood pressure is elevated." Spironolactone (Aldactone) should be taken daily to decrease blood pressure, not only when blood pressure is elevated. Spironolactone (Aldactone) is a potassium-sparing diuretic; therefore, no additional potassium is needed. Adverse reactions include gynecomastia, headache, diarrhea, and cramping. It is important that the client weigh himself daily.
Which instruction would be most appropriate for a client who is taking a diuretic?
"It's okay to take it with food." Instructions for a client taking a diuretic include taking the drug with food or meals if gastrointestinal upset occurs, taking the dose early in the morning to prevent interfering with sleep, implementing safety precautions if dizziness or weakness is a problem, and ensuring adequate fluid intake to prevent fluid rebound. -It is not necessary to lie down after taking the drug.
A client asks, "Why is my prescription being switched from furosemide to spironolactone?" What is the nurse's best response?
"You will lose less potassium with spironolactone than with furosemide." By inhibiting the effects of aldosterone in the distal tubules, spironolactone promotes potassium retention. The client will not have greater potassium losses, water losses, or sodium losses with spironolactone rather than furosemide.
What are the 5 classes of diuretics?
- Thiazide diuretics and thiazide-like diuretics - Loop diuretics - Potassium sparing diuretics - Osmotic diuretics - Carbonic anhydrase inhibitors
Carbonic Anhydrase Inhibitors agents include:
-acetazolamide (Diamox) -dichlorphenamide (Keveyis) -methazolamide (generic)
Potassium-Sparing Diuretic agents include:
-amiloride (Midamor) -eplerenone (Inspra) -spironolactone (Aldactone) -triamterene (Osmitrol)
A client is receiving hydrochlorothiazide. The nurse would expect this drug to begin acting within which time frame?
2 hours Hydrochlorothiazide has an onset of action of 2 hours, peaking in 4 to 6 hours, and lasting approximately 6 to 12 hours.
A client is receiving hydrochlorothiazide. The nurse would expect this drug to begin acting within which time frame? 1 hour 2 hours 3 hours 4 hours
2 hours Hydrochlorothiazide has an onset of action of 2 hours, peaking in 4 to 6 hours, and lasting approximately 6 to 12 hours.
A client receives a dose of furosemide intravenously at 8:00 AM. The nurse would expect this drug to exert is peak effects at which time? 8:15 AM 8:30 AM 8:45 AM 9:00 AM
8:30 AM Furosemide, when given intravenously, begins to act in 5 minutes, reaching peak effects in 30 minutes. In this case, this would be 8:30 AM.
A client has edema of the lower extremities and abdomen. What is the reason to administer a stronger diuretic than a thiazide diuretic to this client? A thiazide diuretic will provide peak effects in 2 hours. A thiazide diuretic will reabsorb potassium in the distal tubule. A thiazide diuretic will be excreted in more than 72 hours. A thiazide diuretic will be ineffective when immediate diuresis is needed.
A thiazide diuretic will be ineffective when immediate diuresis is needed. Thiazide diuretics are ineffective when immediate diuresis is required. A thiazide diuretic acts to reabsorb sodium, not potassium, in the distal convoluted tubule. A thiazide diuretic reaches its peak in 4 to 6 hours. A thiazide diuretic is excreted in 72 hours maximum.
Potassium-Sparing Diuretics are indicated for the treatment of:
Adjunctive treatment of edema caused by HF, liver disease, or renal disease; hypertension; hyperkalemia; and hyperaldosteronism (amiloride; brand name Midamor) (spironolactone; brand name Aldactone) (triamterene; brand name Osmitrol) Improve survival for patients with HF with reduced ejection fraction after acute MI; treatment for hypertension (epelerenone; brand name Inspra)
A nurse is caring for a client with acute renal failure. The health care provider has prescribed a diuretic therapy for the client to promote dieresis. What intervention should the nurse perform to prevent the inconvenience caused by increased urination? Administer the drug early in the day. Ask the client to decrease fluid intake. Gradually increase the drug dosage. Encourage the client to exercise.
Administer the drug early in the day. The nurse should administer the drug early in the day to prevent any nighttime sleep disturbance caused by increased urination when caring for a client receiving a diuretic therapy for acute renal failure. The nurse need not ask the client to decrease fluid intake, gradually increase the drug dosage, or encourage the client to exercise as these are not appropriate interventions and will not help in reducing the discomfort caused by increased urination.
A nurse is providing patient teaching for a 62-year-old woman who is taking triamterene. The nurse will teach the patient to avoid what in her diet? Mushrooms Avocados Bell peppers Fresh pineapple
Avocados The nurse will advise the patient to avoid foods high in potassium, which include apricots, avocados, bananas, cantaloupe, fish, honeydew, kiwi, meat, milk, oranges, potatoes, poultry, prunes, spinach, sweet potatoes, tomatoes, winter squash, and yams. Triamterene achieves its diuretic effect by inhibiting transport of sodium in the distal tubules independent of aldosterone. This mechanism causes increased loss of sodium, water, bicarbonate, and calcium and promotes retention of potassium and magnesium. Hyperkalemia can be a serious adverse effect of the drug.
When describing the action of chlorothiazide, what would a nurse include? Blocking of potassium secretion through the tubule Blocking the action of carbonic anhydrase Acting as an aldosterone antagonist Blocking of the chloride pump
Blocking of the chloride pump Chlorothiazide, a thiazide diuretic, blocks the chloride pump. Carbonic anhydrase inhibitors such as acetazolamide block the action of carbonic anhydrase. Spironolactone, a potassium sparing diuretic, acts as an aldosterone antagonist. Amiloride and triamterene, potassium sparing diuretics, block potassium secretion through the tubule.
An older adult client with a history of heart failure has presented to the emergency department in respiratory distress. Assessment reveals the presence of pulmonary edema, and an infusion of IV furosemide has been prescribed. For the duration of treatment, the nurse should prioritize assessments related to which expected age-related dysfunctions? Select all that apply. Renal function Respiratory function Hepatic function Cardiac function Cognitive function
Cardiac function Renal function Hepatic function In general, dose selection for the older adults requires caution, reflecting the increased likelihood that older adults have decreased cardiac, renal, or hepatic function. This medication therapy with the diuretic furosemide has a lower risk for affecting respirations or cognition.
A 75-year-old client is diagnosed with atrial fibrillation and chronic congestive heart failure. The health care provider orders a combination of digoxin and diuretics to treat the client's diseases. Recent laboratory results indicate that the client's potassium level is 2 mEq/L. This client is at risk for which problem? Congestive heart failure Digoxin toxicity Exacerbation of the atrial fibrillation Subtherapeutic levels of serum digoxin
Digoxin toxicity When digoxin and diuretics are given concomitantly, the risk of digoxin toxicity is increased due to diuretic-induced hypokalemia.
Diuretics increase the production and output of urine. Which statement helps explain how diuretics achieve these effects? Diuretics have no effect on reabsorption. Diuretics reduce the reabsorption of water in the kidneys. Diuretics increase the reabsorption of electrolytes in the kidneys. Diuretics increase production of nephrons.
Diuretics reduce the reabsorption of water in the kidneys. Diuretics increase urine production and output by reducing the reabsorption of water and electrolytes in the kidneys.
An elderly patient with a history of congestive heart failure has been admitted to hospital with failure to thrive and admission blood work reveals a hemoglobin level of 6.9 g/dL. The care team has consequently administered two units of packed red blood cells, but auscultation of the client's lungs now reveals diffuse crackles. Administration of what drug is likely to resolve the patient's pulmonary edema? Mannitol Furosemide Hydrochlorothiazide Triamterene
Furosemide Furosemide can be given intravenously to provide rapid relief from pulmonary edema. -Mannitol is not normally used to treat pulmonary edema and neither HCTZ nor triamterene is used in the acute treatment of pulmonary edema.
After teaching a group of nursing students about diuretics, the instructor determines that the teaching was successful when the group identifies which as a loop diuretic?
Furosemide Furosemide is an example of a loop diuretic. Hydrochlorothiazide is a thiazide diuretic. Acetazolamide is a carbonic anhydrase inhibitor. Spironolactone is a potassium-sparing diuretic.
A client prescribed both an ACE inhibitor and a beta-blocker for the treatment of hypertension has been consistently obtaining blood pressure readings in the vicinity of 145/90 mm Hg. As a result, the client's primary health care provider has prescribed furosemide. What order would be most consistent with this client's health needs? Furosemide 20 mg IV OD Furosemide 40 mg IV TID Furosemide 125 mg PO OD Furosemide 40 mg PO BID
Furosemide 40 mg PO BID For hypertension, furosemide is commonly given as 40 mg PO twice daily and gradually increased if necessary. The other prescriptions include incorrect routes, frequencies, or doses.
A male client has cirrhosis of the liver that has caused ascites. The nurse knows that what condition may occur if diuretics are used to reduce the ascites?
Hepatic encephalopathy Diuretics are often used to manage edema and ascites in clients with hepatic impairment. These drugs must be used with caution, because diuretic-induced fluid and electrolyte imbalances may precipitate or worsen hepatic encephalopathy and coma.
Thiazide Diuretics
Hydrochlorothiazide (HCTZ)
A 91-year-old client, who is being prepared for discharge, has been prescribed the diuretic spironolactone. While teaching the client about the drug, what major adverse effect should the nurse be sure to mention? Angina Hypertension Hyperkalemia Hypokalemia
Hyparkalemia The major adverse effect of potassium-sparing diuretics such as spironolactone is hyperkalemia. Clients receiving these drugs should not be given potassium supplements and should not be encouraged to eat foods high in potassium.
A client who has been taking hydrochlorothiazide arrives at the clinic for his 1-month follow-up appointment. The client tells the nurse that he feels weaker since he began taking the drug. What should the nurse consider as a possible cause of these symptoms? Hyperkalemia Hypercalcemia Hypocalcemia Hypokalemia
Hypokalemia Thiazides, such as hydrochlorothiazide, are potassium-losing diuretics, and their use can lead to hypokalemia. Symptoms of hypokalemia include muscle weakness, arrhythmia, hypotension, anorexia, and shallow respirations.
A health care provider has prescribed a loop diuretic for a client with hypertension. The client also has diabetes mellitus. What condition should the nurse monitor for in this client after administering the prescribed drug?
Increased blood glucose levels The nurse should monitor for increased blood glucose levels in the diabetic client receiving a loop diuretic. The blood glucometer test results for these clients may be elevated, or urine may test positive for glucose. Thiazide diuretic agents may cause gout attacks and sudden joint pain. The nurse need not monitor for a sudden increase in weight as the administration of loop diuretics to a diabetic client will not cause this effect.
When describing where bumetanide acts, what would the nurse include? Loop of Henle Collecting tubule Proximal convoluted tubule Glomerulus
Loop of Henle Bumetanide is a loop diuretic that blocks the chloride pump in the ascending loop of Henle. It also has a similar effect in the descending loop and in the distal convoluted tubule.
A client is diagnosed with increased intracranial pressure. Which would the nurse expect to be ordered?
Mannitol Mannitol is a powerful osmotic diuretic that is used to treat increased intracranial pressure. It is given intravenously and begins to work in 30 to 60 minutes. Furosemide, amiloride, and bumetanide are not indicated for the treatment of increased intracranial pressure.
Which would the nurse expect to find in a client receiving acetazolamide? Metabolic acidosis Metabolic alkalosis Respiratory acidosis Respiratory alkalosis
Metabolic acidosis Metabolic acidosis is a relatively common and potentially dangerous effect that occurs when bicarbonate is lost due to the action of carbonic anhydrase inhibitors. Metabolic alkalosis would occur if bicarbonate were retained. No respiratory acid-base imbalances are associated with this drug.
A client with renal impairment is in need of a diuretic. Because of the renal problem, potassium-sparing diuretics are contraindicated but may be used if there is no other option. If they are used at all, what nursing intervention would be most important for this client? Administration of a thiazide diuretic Monitoring of serum electrolytes, creatinine, and BUN Monitoring of CBC and serum albumin Administration of concurrent potassium
Monitoring of serum electrolytes, creatinine, and BUN Potassium-sparing diuretics are contraindicated in clients with renal impairment because of the high risk of hyperkalemia. If they are used at all, frequent monitoring of serum electrolytes, creatinine, and BUN is needed.
Edema
Movement of fluid into the interstitial spaces; occurs when the balance between osmotic pull (from plasma proteins) and hydrostatic push (from blood pressure) is imbalanced Abnormal accumulation of fluid in interstitial spaces of tissues.
A client is receiving hydrochlorothiazide. The nurse would expect to administer this drug by which route? Subcutaneous Intramuscular Oral Intravenous
Oral Hydrochlorothiazide is only available as an oral preparation. Only chlorothiazide can be given by intravenous infusion.
A client is unconscious and experiencing increasing intracranial pressure. What type of diuretic will the client most likely be prescribed?
Osmotic diuretic An osmotic diuretic is used to reduce intracranial pressure related to a head injury. Loop diuretics, potassium-sparing diuretics, and thiazide diuretics do not reduce intracranial pressure.
A client is prescribed furosemide to treat hypertension. What education should the nurse provide to the client?
Reduce the amount of sodium in the diet Reducing sodium intake in the diet helps diuretic drugs be more effective and allows smaller doses to be taken. Smaller doses are less likely to cause adverse effects. Thus, clients should avoid excessive table salt and obviously salty foods. These foods may aggravate edema or hypertension by causing sodium and water retention. Because diuresis occurs, potassium may be lost and foods higher in potassium may be required. The medication should be taken as prescribed and not doubled due to the side effects that may occur from too much of the medication. Clients should weigh themselves 2 to 3 times per week to assess fluid loss or gain.
What would contraindicate the use of indapamide? Renal disease Diabetes Gout Systemic lupus erythematosus
Renal disease Indapamide would be contraindicated in a client with severe renal disease, which may prevent the diuretic from working or precipitate a crisis stage due to blood flow changes brought about by the diuretic. Indapamide would be used cautiously in clients with diabetes, systemic lupus erythematosus, or gout
A male client has cirrhosis and is receiving diuretic therapy. The nurse knows that what drug will help prevent metabolic alkalosis or hypokalemia in this client? Hydrochlorothiazide Dyazide Bumetanide Spironolactone
Spironolactone For clients with cirrhosis, diuretic therapy should be initiated in a hospital setting, with small doses and careful monitoring. To prevent hypokalemia and metabolic alkalosis, supplemental potassium or spironolactone may be needed.
An adult client with a diagnosis of hypertension has been prescribed oral furosemide. What goal should the nurse identify when planning this client's medication teaching session? The client will be able to demonstrate correct technique for blood glucose monitoring. The client will accurately describe the basic structure and functions of the kidneys. The client will describe the rationale for increasing fluid intake. The client will identify strategies for limiting sodium intake.
The client will identify strategies for limiting sodium intake. The reason for furosemide use should guide client teaching. In most instances, it is necessary to initiate measures to limit sodium intake. Key considerations should include not adding salt to food during preparation or at the dinner table, reading food labels carefully to be aware of hidden sources of sodium, and avoiding processed or high-sodium foods. -Blood glucose monitoring is not indicated, and there is no need for increased fluid intake. -Renal anatomy and physiology are not priority teaching points.
A 64-year-old patient is admitted to the emergency department with pulmonary edema. The physician orders furosemide 40 mg IV. If the drug is available in a 100 mg/10 mL preparation, how will the nurse administer it?
The nurse will administer 4 mL over 1 to 2 minutes. For treatment of pulmonary edema in an adult patient, 40 mg of furosemide is administered intravenously over 1 to 2 minutes. (The dose can be increased to 80 mg if the first infusion fails to resolve the condition.) If the preparation is 100 mg/10 mL, this will require infusing 4 mL of the preparation. (40 mg x 10 mL/100 mg = 4 mL.)
Carbonic Anhydrase Inhibitors are indicated for the treatment of:
Treatment of edema, glaucoma; adjunctive treatment of epilepsy, altitude sickness (acetazolamide; brand name Diamox) Treatment of primary hyperkalemic paralysis (dichlorphenamide; brand name Keveyis) Treatment of glaucoma (methazolamide)
Osmotic Diuretics are indicated for the treatment of:
Treatment of elevated intracranial pressure, acute renal failure,
osmotic pull
drawing force of large molecules on water, pulling it into a tubule or capillary; essential for maintaining normal fluid balance within the body; used to draw out excess fluid into the vascular system or the renal tubule
A 49-year-old client reports frequent muscle cramps while on hydrochlorothiazide therapy. The nurse would advise the client to do which? include high-sodium foods in her diet. drink plenty of fluids. take calcium supplements. eat potassium-rich foods.
eat potassium-rich foods The client is most likely experiencing muscle cramps due to potassium loss. Therefore, the nurse should advise the client to include potassium supplements in the diet. Drinking plenty of fluids or using calcium supplements will not reduce the occurrence of cramps. It is important to caution the client to avoid foods high in sodium because they could counteract the effects of drug therapy.
Hyperaldosteronism
excessive output of aldosterone from the adrenal gland, leading to increased sodium and water retention and loss of potassium
Loop Diuretics agents include:
furosemide, bumetanide, torsemide
A health care provider prescribes spironolactone, a potassium-sparing diuretic, for a client with cirrhosis. For which category of clients is the use of potassium-sparing diuretics contraindicated?
hyperkalemia The nurse should know that potassium-sparing diuretics are contraindicated in clients with hyperkalemia and are not recommended for children. Potassium-sparing diuretics should be used cautiously in clients with liver disease, diabetes, or gout, but presence of these conditions does not contraindicate the use of potassium diuretics.
A health care provider prescribes spironolactone, a potassium-sparing diuretic, for a client with cirrhosis. For which category of clients is the use of potassium-sparing diuretics contraindicated? gout hyperkalemia diabetes liver disease
hyperkalemia The nurse should know that potassium-sparing diuretics are contraindicated in clients with hyperkalemia and are not recommended for children. Potassium-sparing diuretics should be used cautiously in clients with liver disease, diabetes, or gout, but presence of these conditions does not contraindicate the use of potassium diuretics.
A physician has prescribed triamterene to a client with renal disease. The client informs the nurse that they are taking potassium supplements to address some heart problems. The nurse would be alert for which of the following?
increased risk of hyperkalemia The nurse should inform the client about the increased risk of hyperkalemia as the effect of the interaction between triamterene, which is a potassium-sparing diuretic, and potassium supplements. When the client is administered loop diuretics with anticoagulants or thrombolytics, there will be increased risk of bleeding. When the client is administered digitalis with loop diuretics, there is an increased risk of arrhythmias. Decreased diuretic effect, in this case decreased effect of triamterene, will occur when a potassium-sparing diuretic such as triamterene is administered with NSAIDs, salicylates, and anticoagulants.
Hypokalemia
low potassium in the blood, which often occurs after diuretic use; characterized by weakness, muscle cramps, trembling, nausea, vomiting, diarrhea, and cardiac arrhythmias
Osmotic Diuretics agents include:
mannitol (Osmitrol)
high ceiling diuretics
powerful diuretics that work in the loop of Henle to inhibit the reabsorption of sodium and chloride, leading to a sodium-rich diuresis
fluid rebound
reflex reaction of the body to the loss of fluid or sodium; the hypothalamus causes the release of antidiuretic hormone, which promotes water retention, and stress related to fluid loss combines with decreased blood flow to the kidneys to activate the renin-angiotensin-aldosterone system, leading to further water and sodium retention
Alkalosis
state of not having enough acid to maintain homeostatic processes The buildup of excess base (lack of acids) in the body fluids. PH above 7.45
