NCLEX-RN cheat sheet · Cardiovascular

Heart failure

Left vs right, BNP and ejection fraction, drug checks, daily weights

AI-checkedChecked by AI against current guidelines, with spot-checks by a registered nurse.

Heart failure means impaired filling, pumping, or both. It can occur with a preserved ejection fraction, and resting output isn't always low.

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At a glance

Left-sided or right-sided

	Left-sided: fluid backs into the lungs	Right-sided: fluid backs into the body
Common causes	High blood pressure, coronary disease, a heart attack, valve disease	Left-sided failure, or pulmonary hypertension
Signs	Breathless on exertion, crackles, trouble breathing lying flat, sudden breathlessness that wakes the client at night	Swollen legs and ankles, a swollen belly, poor appetite, an enlarged liver, distended neck veins
Output and EF	Can fall: an extra heart sound (S3), weak pulses, cool, pale hands and feet	Ejection fraction often normal
Complications	Pulmonary edema, with pink, frothy sputum	Liver and kidney damage; venous stasis ulcers

Simple rule: Left is lungs; right is the rest of the body. Many clients have both: over time, left-sided failure strains the right side too.

Tests

Test	What it shows
BNP	A protein the heart releases under strain; a high level points to heart failure
BNP under 100 pg/mL	Failure less likely, not impossible: BNP can be low in obesity and some failure with a preserved ejection fraction
Echocardiogram	Ejection fraction: normal about 55 to 70%. Left-sided failure can reduce it or leave it preserved
Chest X-ray, ECG	Heart size and fluid in the lungs; rhythms that lower output

Acute decompensation

A sudden or gradual worsening that needs unplanned care. In up to half of cases, no cause is found.
Triggers: missed medicines, too much salt, uncontrolled blood pressure, arrhythmias, lung flares, kidney disease, anemia.
Report promptly: worse breathing, swelling and lung sounds, new confusion, less urine.
Treatment often includes IV diuretics and oxygen.

Heart association classes: I: no limits. II: slight. III: marked. IV: symptoms at rest. Know each client's baseline class.

Heart failure drugs: what to check

Drug	Watch for	Check and teach
Loop diuretic: furosemide	Low potassium and dehydration: thirst, weakness, cramps, low pressure, little urine, arrhythmias. Fast IV infusion can damage hearing	Check potassium first. Give in the morning when you can. Give IV slowly
Spironolactone (potassium-sparing)	High potassium; breast enlargement in men	Check potassium within a week of starting, then regularly. Higher risk with kidney problems, potassium supplements, potassium-containing salt substitutes, ACE inhibitors or ARBs
ACE inhibitor (-pril), ARB (-sartan)	Dry cough (less with ARBs), high potassium, angioedema	Monitor pressure, potassium and kidney function. Teach clients not to use salt substitutes that contain potassium without asking their provider. Boxed warning: fetal harm, so stop when pregnancy is found
Beta blocker	Slow pulse, low pressure	Stable HFrEF: specific evidence-based beta blockers, not just any. Apical pulse first. Never stop suddenly: it's tapered over 1 to 2 weeks
Digoxin	Toxicity: nausea, vomiting, poor appetite, fatigue, halos and arrhythmias, which can come first, especially in children. Low potassium raises the risk	Apical pulse for a full minute: under 60, hold and notify the prescriber, unless other parameters are ordered. Antidote: digoxin immune fab

Follow the order: Before these drugs, check the pulse, blood pressure and potassium. Orders often include hold parameters: below them, hold the drug and notify the prescriber.

Diet, fluids and nursing care

Avoid excessive sodium; the exact goal is set by the clinician's orders.
Fluid limits are individual, and their benefit is uncertain. Ice chips count in the limit.
Daily weights, intake and output, and lung sounds tell you whether the plan is working.
Breathless: raise the head of the bed, give oxygen as ordered, balance activity with rest.
Know each client's baseline edema, lung sounds, mental status and kidney function, so you can spot a change.

Teaching: daily weights and what to report

Weigh every morning on the same scale, at the same time, in similar clothing. Keep a journal of weight and blood pressure for each appointment.
Report a gain over 2 to 3 lb in a day, or 5 lb in a week. A kilogram gained in a day is about a liter of fluid.
Also report more breathlessness or tiredness, a racing heart, worse swelling, rising home blood pressures or a tight waistband. Family may notice confusion first.
Sleep with the head raised on pillows or in a recliner. Choose low-sodium, heart-healthy foods.
Take every dose, even when feeling well. Rise slowly. Take a morning diuretic early, to avoid getting up at night.

Is the plan working?

Example goals: oxygen saturation above 92%, less edema, a lower weight, better exercise tolerance.
Working: fewer crackles, less swelling, a falling weight.
Goals not met: the plan is revised with the team.
Encourage structured exercise, weight control and stopping smoking. Cardiac rehab helps clients stay out of hospital.

Priority and safety calls

★ Pulmonary edema (anxiety, severe breathlessness, crackles, falling oxygen, pink frothy sputum): raise the head of the bed and report it at once.
★ A weight gain since yesterday and needing more pillows to sleep: assess lung sounds and oxygen saturation first.
Digoxin with nausea and yellow halos, and a low potassium: hold the digoxin and notify the prescriber.
Swelling of the lips, tongue, face or throat on an ACE inhibitor is angioedema, an emergency: stop the drug, protect the airway, get help.
Don't lie a breathless client flat; it makes breathing worse.
A client who stops a potassium supplement, thinking it's just a vitamin, can slide into digoxin toxicity: teach why it matters.

How the NCLEX tests it

Left-sided failure fills the lungs; right-sided failure swells the body.
Daily weights catch it early: report 2 to 3 lb a day, or 5 lb a week.
A high BNP points to heart failure; under 100 pg/mL makes it less likely, not impossible.
Furosemide drops potassium; spironolactone raises it. Low potassium makes digoxin toxicity more likely.
Digoxin or a beta blocker: full-minute apical pulse; under 60, hold and notify unless other parameters are ordered.
Treatment is working when crackles, swelling and weight fall.
Traps: weighing at different times, lying a breathless client flat, and potassium salt substitutes on an ACE inhibitor.

Practice it next

This sheet comes from Heart failure and Cardiovascular drugs I: blood pressure and heart failure in our NCLEX-RN course. Try free practice questions, or see the lessons it was written from.

Free NCLEX practice questions The NCLEX-RN course

Quick self-quiz

Left-sided failure backs fluid into the ___.
Show answer
lungs
A BNP under ___ pg/mL makes heart failure less likely, not impossible.
Show answer
100
A normal ejection fraction is about 55 to ___%.
Show answer
70
Report a weight gain over 2 to 3 lb in a day, or ___ lb in a week.
Show answer
5
Hold digoxin for an apical pulse under ___, unless other parameters are ordered.
Show answer
60
The antidote for digoxin toxicity is digoxin immune ___.
Show answer
fab
Fast IV furosemide can damage the ___.
Show answer
hearing

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Sources

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