Cardiac Drugs Diuretics & Nitrates

Diuretics

• Thiazide

• Loop

• Potassium Sparing 

Thiazide Diuretics

• Hydrochlorothiazide (HCTZ)

• Drug of choice for hypertension

• Routes: PO or IV

Thiazide Diuretics Mechanism of Action 

• Inhibits reabsorption of sodium & chloride

• Increases secretion of sodium and water

• Decreases plasma volume

• Decreases preload & workload of the heart

• Decreases blood pressure

Thiazide Diuretics Uses

• Blood pressure management

• Fluid retention (edema)

  • heart failure

Thiazide Diuretics Adverse Effects 

• Low blood pressure (hypotension)

• Electrolyte imbalances

  • Especially potassium and sodium

• Ototoxicity

  • More likely with existing kidney issues

  • When taken with other ototoxic drugs concurrently

Drugs that increase the effects of Thiazide Diuretics

• ETOH,

• barbiturates,

• MAOIs,

• Beta Blockers,

• corticosteroids

Drugs that decrease the effects of Thiazide Diuretics

• NSAIDs

Thiazide Diuretics Nursing Implications

• Check BP

• Check electrolytes

  • Especially Potassium & sodium

• Watch for:

  • Dehydration

  • Signs of Hypotension

Thiazide Diuretics Cautions

• Caution with allergy to sulfa meds

• Caution with pregnancy

Loop Diuretics

• Inhibit Na & Cl reabsorption in loop of Henle

• Produces significant diuresis

Furosemide (Lasix)

• Loop Diuretic 

• Rapid effect

  • Diuretic of choice when rapid diuresis is needed.

• Recommended when kidney function is impaired

  • But - pt has to be able to make urine or it won't work

• Dosing can be titrated for maximum effect

• Most effective and most versatile

• Available PO and IV

Furosemide (Lasix) Uses

• Heart failure

• Pulmonary edema

• Hepatic disease

• Renal disease

• Hypertension

Furosemide (Lasix) Adverse Effects

• Electrolyte imbalances

  • Esp. Na+ & K+

  • May need supplementation

• Dehydration

• Ototoxicity

• Hypotension

Furosemide (Lasix) Contraindication

• No urine output

Furosemide (Lasix) Nursing Implications

• Prior to administration check:

  • BP

  • Labs (Na, K, BUN/Creat) and glucose levels if pt is diabetic

• After administration monitor:

  • BP

  • I/O

  • Signs of fluid reduction: decreased edema, lungs more clear, etc.

• Monitor for side effects

  • Electrolyte disturbances

  • Dehydration: Skin turgor, tachycardia

Drugs that decrease the effects of Furosemide (Lasix)

• Ibuprofen

• phenytoin

Drugs that increase effects of Furosemide (Lasix)

• Corticosteroids and digoxin

Spironolactone (Aldactone)

• Potassium Sparing Diuretics 

• Combine with loop diuretics

  • Reduces potassium loss

  • Lower dosage of loop needed

• Administered PO

• Up to 6 weeks for maximum effect

Potassium Sparing Diuretics Mechanism of Action

• Blocks aldosterone

• Promotes water and sodium excretion & potassium retention

Spironolactone (Aldactone) Uses 

• Heart failure

• Ascites

• Hypokalemia

• Hypertension

• Hyperaldosteronism

Spironolactone (Aldactone) Adverse Effects 

• Dizziness

• HA

• Abd cramping

• Diarrhea

• Increased serum K+ levels

Spironolactone (Aldactone) Contraindications

• Abnormal kidney function

• 1^st trimester of pregnancy

Spironolactone (Aldactone) Black Box Warning

• May cause tumor growth

• Unnecessary use should be avoided

Spironolactone (Aldactone) Nursing Implications

• Give same time each day

  • Preferably in the morning

  • Can take with food to help with Gl issues

  • Take even if they feel fine

• Similar to loop diuretics

  • Check BP, electrolytes, BUN/creatinine before administering

  • Watch for signs of dehydration, electrolyte imbalance

Spironolactone (Aldactone) Food & Drug Interactions 

• lithium & digoxin can reach toxic levels

• Ginger, licorice increase effects

Drugs that Increase the effects of Spironolactone (Aldactone)

• ACE

• ARB

• K containing drugs

• Beta Blockers

Drugs that decrease the effects of Spironolactone (Aldactone)

• ETOH,

• vasodilators,

• salicylates

Angina

• Lack of perfusion & oxygenation to heart

• Pain in heart

  • May cause other symptoms too

Coronary Artery Disease

• Increased plaque accumulation

• Narrowed artery blocked by a blood clot

Drugs to treat angina

• Organic Nitrates

• Beta blockers

• Calcium channel blockers

Organic Nitrates

• Use

  • Angina

• Usually used PRN

  • Can be given as ongoing treatment

• Works fast

• Multiple routes of administration

  • IV, Sublingual, PO, Topical transdermal & disc

Organic Nitrates Mechanism of Action

• Cause vasodilation

• Opens coronary arteries

• Improves perfusion to heart

• Also decreases workload of heart

  • Via preload and afterload

Organic Nitrates Examples

• Nitroglycerin

• isosorbide mononitrate

• isosorbide dinitrate

Organic Nitrates Adverse Effects

• Severe headache

  • Common

  • Tx with acetaminophen

• Hypotension & Orthostatic Hypotension

• Bradycardia

• Dizziness

• Syncope

Organic Nitrates Contraindications

• Erectile Dysfunction Meds

  • Hypotension Warning!

• Severe anemia

• Hypotension

• Hypovolemia

Organic Nitrates Are Cautioned With

• Head injury

• Cerebral hemorrhage

• Beta Blockers

• Abnormal kidney function

Organic Nitrates Nursing Implications

• Prior to administration check:

  • BP (HOLD if systolic < 90 or 30 mm Hg below the pt normal BP)

  • HR (HOLD HR > 100 )

  • Chest pain level

  • Last time ED med taken

  • If new onset chest pain in hospital call PCP and get EKG order

• After administration

  • Reassess pain, BP

  • Monitor for adverse effects

Sublingual Organic Nitrates Nursing Implications

• Comes in brown bottle / Exposure to light deactivates med

• Keep in cool, dry place

• Replace every 6 months

• Should tingle when placed under tongue or it isn’t going to work

PO Organic Nitrates Nursing Implications

• Take in the morning after nitrate free night

• Take 1-2 hours before meal

• Do not crush/break or chew sustained release form

Ointment Organic Nitrates Nursing Implications

• Must use dose measuring application papers

IV Organic Nitrates Nursing Implications

• done in ICU or step down units