Heart Failure and Cardiac Dysrhythmias - Revision Notes
Heart failure (HF) and cardiac dysrhythmias are among the most heavily tested topics in the NLE Board Examination for Nurses. As a BSN graduate preparing for the PRC Board Exam, you must master the pathophysiology, clinical manifestations, nursing diagnoses, priority interventions, and pharmacology related to these conditions. Under RA 9173 (Philippine Nursing Act of 2002), registered nurses are accountable for safe, competent, and evidence-based cardiovascular nursing care. These revision notes are organized to help you quickly recall high-yield concepts, apply the nursing process, and use Maslow's Hierarchy to prioritize care — all essential skills for the NLE.
Heart Failure: Pathophysiology and Compensatory Mechanisms
Formulas
Cardiac Output (CO) = Heart Rate (HR) × Stroke Volume (SV)
Example
Normal: CO = 72 bpm × 70 mL = ~5 L/min. In HF with low SV of 40 mL: CO = 80 bpm × 40 mL = 3.2 L/min — still reduced despite compensatory tachycardia.
Variables
CO = cardiac output (L/min); HR = heart rate (beats/min); SV = stroke volume (mL/beat)
Application
In heart failure, SV decreases because the left ventricle cannot contract effectively. The compensatory SNS response increases HR to maintain CO, but this is only temporary.
Exam tips
- NLE FAVORITE: The echocardiogram measures ejection fraction — it is the most definitive test for HF type.
- BNP > 100 pg/mL = think HF in any dyspneic patient scenario.
- Drugs that BLOCK compensatory mechanisms (ACE-I, beta-blockers, spironolactone) are the cornerstone of HF treatment — know their mechanisms.
- Philippine context: Hypertension is the #1 cause of HF in the Philippines — PhilPEN addresses this at the RHU/barangay health center level.
Key points
- Heart failure (HF) is a clinical syndrome where the heart CANNOT pump enough blood to meet the body's metabolic demands.
- Common causes in the Philippine setting include hypertension (HTN), coronary artery disease (CAD), myocardial infarction (MI), rheumatic heart disease (valvular), and cardiomyopathy.
- The DOH PhilPEN (Philippine Package of Essential NCD Interventions) program at the primary-care level targets HTN and NCD control to prevent HF progression.
- Compensatory mechanisms are initially helpful but become MALADAPTIVE over time.
- Three main compensatory mechanisms: (1) Sympathetic Nervous System (SNS) activation — increases heart rate (HR) and contractility; (2) Renin-Angiotensin-Aldosterone System (RAAS) — causes Na+ and water retention, increasing preload; (3) Ventricular hypertrophy and dilation — the heart muscle thickens and enlarges to pump harder.
- Maladaptive effects: increased afterload, fluid overload, ventricular remodeling — all WORSEN the failure.
- HF drugs (ACE inhibitors, beta-blockers, spironolactone) work by BLOCKING these compensatory systems.
- Ejection Fraction (EF): Normal is 55–70%; reduced EF (<40%) = HFrEF (systolic HF); preserved EF (≥50%) = HFpEF (diastolic HF).
Definitions
Preload
The volume of blood in the ventricle at the END of diastole (end-diastolic volume). It represents the stretch on the ventricular muscle before contraction.
Importance
In HF, RAAS activation increases preload through Na+ and water retention. Loop diuretics and nitrates REDUCE preload. High preload in left HF causes pulmonary congestion.
Afterload
The resistance the ventricle must overcome to eject blood during systole. In systemic circulation, afterload is primarily determined by systemic vascular resistance (SVR).
Importance
In HF, SNS activation causes vasoconstriction, increasing afterload and making the failing heart work HARDER. ACE inhibitors and hydralazine REDUCE afterload.
Ejection Fraction (EF)
The percentage of blood ejected from the left ventricle with each heartbeat. Measured by echocardiogram. Normal is 55–70%.
Importance
A reduced EF (<40%) confirms systolic HF. The echocardiogram is the GOLD STANDARD diagnostic test. This is frequently asked in NLE.
BNP (B-type Natriuretic Peptide)
A hormone released by the ventricles in response to increased wall stress and volume overload. Normal is <100 pg/mL; elevated in HF.
Importance
BNP correlates directly with the SEVERITY of HF. It is used to DIAGNOSE and MONITOR HF. Levels above 100 pg/mL suggest HF in a dyspneic patient.
Ventricular Remodeling
Structural changes in the myocardium (hypertrophy, dilation, fibrosis) that occur as a maladaptive response to chronic HF.
Importance
ACE inhibitors, ARBs, beta-blockers, and spironolactone REDUCE or REVERSE remodeling, which is why they improve long-term survival in HF.
Common mistakes
- Confusing PRELOAD and AFTERLOAD: Remember — PRELOAD is what fills the heart BEFORE contraction (volume); AFTERLOAD is the resistance the heart pumps AGAINST during contraction (pressure).
- Thinking compensatory mechanisms are always beneficial — they eventually WORSEN heart failure (maladaptive).
- Forgetting that RAAS activation causes both Na+ AND water retention, not just sodium.
- Mixing up HFrEF (reduced EF, systolic dysfunction) and HFpEF (preserved EF, diastolic dysfunction) — NLE may distinguish these.
Left-Sided vs. Right-Sided Heart Failure: Clinical Manifestations
Exam tips
- NLE MEMORY TRICK: L for Left = L for Lungs (pulmonary signs); R for Right = R for Rest of body (systemic signs).
- If the NLE scenario describes 'frothy, pink-tinged sputum with crackles' — this is LEFT HF / pulmonary edema.
- If the NLE scenario describes 'swollen ankles, JVD, enlarged liver, weight gain' — this is RIGHT HF.
- Nursing priority based on Maslow: BREATHING problems (left HF) take priority over FLUID issues (right HF).
- S3 gallop = decreased cardiac output = hallmark of LEFT HF = NLE favorite.
Key points
- MEMORY TRICK: Left = Lungs; Right = Rest of the body (systemic).
- LEFT-SIDED HF: Blood backs up into the PULMONARY circulation (lungs) because the left ventricle cannot pump forward effectively.
- RIGHT-SIDED HF: Blood backs up into the SYSTEMIC venous circulation because the right ventricle cannot pump blood into the pulmonary artery. The most common cause of right HF is LEFT HF.
- Most patients eventually develop BIVENTRICULAR failure (both sides).
- NANDA Nursing Diagnoses for HF: Decreased Cardiac Output; Excess Fluid Volume; Impaired Gas Exchange; Activity Intolerance; Deficient Knowledge.
- Maslow Priority: Oxygenation and hemodynamic stability are ALWAYS the highest priority (physiologic/safety needs first).
- LEFT HF key signs: Dyspnea on exertion → orthopnea → paroxysmal nocturnal dyspnea (PND) → pulmonary edema. Crackles (rales) on auscultation. Frothy, pink (blood-tinged) sputum. S3 gallop (hallmark of left HF). Tachycardia, fatigue, restlessness from hypoxia.
- RIGHT HF key signs: Peripheral and dependent edema (ankles, sacrum). Weight gain. Jugular venous distention (JVD). Hepatomegaly (enlarged liver) and ascites. Anorexia, nausea from GI congestion. Right upper quadrant discomfort.
- Orthopnea: breathlessness when lying flat — patient needs 2 or more pillows to sleep; documented as '2-pillow orthopnea.'
- Paroxysmal Nocturnal Dyspnea (PND): sudden awakening from sleep with severe shortness of breath — caused by redistribution of fluid when patient lies down at night.
Definitions
Orthopnea
Breathlessness (dyspnea) that occurs when a patient lies flat, relieved by sitting or standing upright. Caused by redistribution of fluid from the peripheral tissues into the pulmonary circulation when supine.
Importance
A classic sign of LEFT-sided HF. Nursing intervention: Position the patient in SEMI-FOWLER'S or HIGH FOWLER'S position. Frequently tested in NLE.
Paroxysmal Nocturnal Dyspnea (PND)
Sudden onset of severe breathlessness occurring 1–2 hours after falling asleep, which awakens the patient. The patient must sit upright or go to a window for air.
Importance
Pathognomonic of LEFT-sided HF. Caused by nocturnal fluid redistribution and reabsorption from dependent areas into the pulmonary circulation.
S3 Gallop
A third heart sound heard immediately after S2, creating a 'Kentucky' cadence (lub-dub-ta). It is caused by rapid ventricular filling in a dilated, poorly compliant ventricle.
Importance
The S3 gallop is the HALLMARK auscultatory finding of LEFT-sided HF and decreased cardiac output. It indicates ventricular dysfunction.
Jugular Venous Distention (JVD)
Visible distention of the external or internal jugular veins when the patient is at 45° position. Reflects elevated central venous pressure (CVP).
Importance
Classic sign of RIGHT-sided HF (systemic venous congestion). Measured at a 45-degree angle — if visible above 3–4 cm above the sternal angle, it is abnormal.
Dependent Edema
Edema that occurs in the most gravity-dependent areas of the body. In ambulatory patients, it is found in the ankles and feet. In bedridden patients, it is found in the sacrum and presacral area.
Importance
Classic sign of RIGHT-sided HF. The nurse must assess the SACRAL AREA for edema in bedbound patients — not just the ankles.
Common mistakes
- Forgetting to assess the SACRAL area for edema in bedridden patients — dependent edema shifts to the sacrum, not the ankles, when the patient is lying down.
- Attributing ALL respiratory symptoms to left HF without considering biventricular failure.
- Confusing S3 (normal in young adults but pathological in adults >40 = HF) with S4 (associated with hypertension and reduced ventricular compliance).
- Forgetting that the most common cause of RIGHT-sided HF is LEFT-sided HF — always think of it as a continuum.
- Missing that anorexia and nausea in RIGHT HF are due to GI/hepatic CONGESTION, not a GI disease.
Acute Pulmonary Edema: Emergency Nursing Management
Exam tips
- NLE PRIORITY: In pulmonary edema, the FIRST nursing action is ALWAYS positioning — HIGH FOWLER'S with legs dangling. Then oxygen, then medications.
- Remember LMNOP: Legs dependent → Morphine → Nitrates → Oxygen → Pump (furosemide).
- Furosemide IV has a DUAL action in pulmonary edema: (1) venodilation within minutes (rapid preload reduction before diuresis starts), then (2) diuresis to remove fluid.
- NLE SCENARIO CLUE: 'Patient woke up at 3 AM, cannot breathe, using multiple pillows, frothy pink sputum' = ACUTE PULMONARY EDEMA = HIGH FOWLER'S + O2 + IV furosemide.
- In the Philippine hospital setting (DOH hospitals), always document and report the emergency response per hospital protocol as required under RA 9173 standards of nursing practice.
Key points
- Acute pulmonary edema is a MEDICAL EMERGENCY — fluid rapidly floods the alveoli, impeding gas exchange. It is usually caused by ACUTE DECOMPENSATED LEFT HF.
- Clinical picture: Severe, sudden dyspnea; extreme anxiety ('air hunger'); pink, frothy sputum; crackles throughout ALL lung fields; tachypnea; hypoxia (SpO2 dropping rapidly); diaphoresis; cyanosis.
- PRIORITY NURSING INTERVENTION: Position the patient in HIGH FOWLER'S (90°) with LEGS DEPENDENT (feet dangling off bed). This REDUCES venous return (preload) to the heart and lungs and improves breathing mechanics.
- Why legs DEPENDENT? It traps blood in the lower extremities through gravity, reducing the amount of fluid returning to the overloaded pulmonary circulation.
- MNEMONIC: 'LMNOP' for acute pulmonary edema management: L = Legs dependent / High Fowler's; M = Morphine IV (reduces anxiety, preload, dyspnea); N = Nitrates (vasodilators, reduce preload/afterload); O = Oxygen (high-flow, prepare for NIV/BiPAP); P = Pump (IV Loop diuretic — furosemide).
- Furosemide (Lasix) IV — given IV for IMMEDIATE action (onset within 5–15 minutes); causes rapid diuresis to remove excess fluid.
- Morphine — reduces the sensation of breathlessness, decreases anxiety (which worsens O2 consumption), and causes mild vasodilation (reduces preload). MONITOR for respiratory depression.
- Nitrates (NTG) — powerful venodilators that RAPIDLY reduce preload; given sublingually, IV drip, or as spray. Hold if systolic BP < 90 mmHg.
- Continuous monitoring: SpO2, RR, HR, BP, cardiac rhythm, urine output, and mental status.
- NANDA Priority Nursing Diagnosis: Impaired Gas Exchange related to alveolar-capillary membrane changes (fluid in alveoli).
Definitions
Acute Pulmonary Edema
A life-threatening emergency in which fluid (plasma) rapidly accumulates in the alveoli and interstitium of the lungs, severely impairing gas exchange. Most commonly caused by acute decompensated left-sided heart failure.
Importance
This is an NLE HIGH-PRIORITY scenario. The nurse must recognize it instantly and intervene IMMEDIATELY with position, oxygen, and medications.
NIV / BiPAP (Non-Invasive Ventilation / Bilevel Positive Airway Pressure)
A form of respiratory support that delivers positive pressure through a face mask (not an endotracheal tube). It keeps alveoli open and improves oxygenation without intubation.
Importance
Used in severe pulmonary edema when high-flow O2 alone is insufficient. The nurse prepares the equipment and monitors for patient comfort and effectiveness.
Common mistakes
- Positioning the patient SUPINE or SEMI-RECUMBENT instead of HIGH FOWLER'S with legs DEPENDENT — this is a critical error.
- Giving furosemide PO (oral) instead of IV in acute pulmonary edema — IV is required for rapid onset.
- Forgetting to CHECK systolic BP BEFORE giving nitrates — do NOT give if SBP < 90 mmHg.
- Forgetting to monitor for RESPIRATORY DEPRESSION after giving morphine.
- Treating the numbers (ECG rhythm) rather than the PATIENT — always assess hemodynamics first.
Chronic Heart Failure: Nursing Management and Patient Teaching
Exam tips
- NLE CRITICAL: Weight gain of 1 kg/day or 2.5 kg/week = call the doctor. This number is tested repeatedly on the board exam.
- Patient teaching about digoxin: check APICAL pulse for 1 full minute BEFORE each dose; hold if <60 bpm; report nausea, visual changes, slow pulse.
- Salt substitutes contain POTASSIUM — warn patients on ACE inhibitors or spironolactone to avoid them (hyperkalemia risk).
- The nursing diagnosis 'Deficient Knowledge' related to HF self-management is commonly paired with patient teaching scenarios in NLE.
- Philippine context: PhilPEN and the Malasakit Program support NCD management; as a nurse under RA 9173, you are responsible for health education as an independent nursing function.
Key points
- DAILY WEIGHT MONITORING is the cornerstone of HF self-management. Weigh at the SAME TIME each day, after urinating, before eating, on the SAME scale, wearing the SAME type of clothing.
- REPORT immediately: Weight gain of 1 kg (about 2 lbs) in 1 DAY or 2.5 kg (about 5 lbs) in 1 WEEK — this signals fluid retention (decompensation).
- Sodium restriction: Typically 2,000–3,000 mg Na per day (low-sodium diet). Avoid processed foods, canned goods, bagoong, patis, toyo, instant noodles — common Filipino dietary challenges.
- Fluid restriction: Usually 1.5–2 liters per day if ordered. Teach patient to measure fluid intake including all soups, ice cream, and gelatin.
- Position: Semi-Fowler's to High Fowler's during rest and sleep to ease breathing.
- Activity: Balance rest and activity. Cardiac rehabilitation and graded exercise as tolerated. Avoid activity after meals (increases cardiac demand).
- Monitor I&O (intake and output) every shift; monitor daily weight; auscultate lung sounds every shift for crackles; assess peripheral edema (grade 0–4+).
- NANDA Nursing Diagnoses for Chronic HF: Decreased Cardiac Output; Excess Fluid Volume; Activity Intolerance; Ineffective Health Management; Deficient Knowledge (Patient Teaching).
- Teach patient: Medication compliance (never skip digoxin without checking pulse; never stop beta-blockers abruptly); signs of worsening HF; when to call the doctor; pulse-taking technique before digoxin.
- Follow-up care: Reinforce compliance with clinic visits, laboratory monitoring (electrolytes, BNP, creatinine), and weight logs.
Definitions
Graded Peripheral Edema Scale
A standardized clinical rating for pitting edema: 1+ = slight pitting (2mm), barely noticeable; 2+ = moderate pitting (4mm), indentation subsides rapidly; 3+ = deep pitting (6mm), indentation remains for a short time; 4+ = very deep pitting (8mm), indentation lasts a long time. Limb may appear distorted.
Importance
Used by nurses to objectively document and TRACK changes in edema. Trending edema grades helps evaluate treatment effectiveness.
Sodium Restriction (Low-Na Diet)
A dietary modification limiting sodium intake to 2,000–3,000 mg per day to reduce fluid retention. Sodium causes water retention, increasing preload and worsening HF.
Importance
Critical patient teaching point in Philippine settings where salty foods (bagoong, patis, toyo, processed meats) are common in the diet.
Common mistakes
- Teaching the patient to weigh themselves at different times of day — this gives inaccurate trending.
- Forgetting to specify 'same scale, same clothing, after first void in the morning' in patient teaching.
- Allowing the patient to use salt substitutes — most contain POTASSIUM CHLORIDE which can cause hyperkalemia especially in patients on spironolactone or ACE inhibitors.
- Restricting sodium without also educating about HIDDEN sodium sources (canned goods, instant noodles, processed meats) common in Filipino diets.
- Not teaching the patient to check the APICAL PULSE before taking digoxin — a key medication safety teaching point.
Cardiac Dysrhythmias: Recognition and Management
Exam tips
- NLE FORMULA: Patient assessment FIRST → Check pulse → Check BP → Then decide on intervention.
- ARREST RHYTHMS (no pulse): VF, Pulseless VT → CPR + DEFIBRILLATE (shockable). Asystole, PEA → CPR + EPINEPHRINE (not shockable).
- AFib = irregularly irregular + no P waves + stroke risk = ANTICOAGULATION is mandatory.
- REMEMBER: Defibrillation = D for Disorganized (VF/pulseless VT). Cardioversion = C for Controlled timing (synchronized).
- For NLE scenarios involving the nurse's FIRST action in cardiac arrest: Call for help / activate emergency response → Start CPR → Attach AED/defibrillator → Defibrillate if shockable.
Key points
- A dysrhythmia is any disturbance in the RATE, RHYTHM, or CONDUCTION of the heartbeat.
- MOST IMPORTANT RULE: Always assess the PATIENT first — not just the ECG. Ask: Is the patient conscious? Do they have a pulse? Are they hemodynamically stable (BP, mental status)?
- SINUS BRADYCARDIA: Regular rhythm, rate <60 bpm. P waves present. PR interval normal. Treat only if SYMPTOMATIC (dizziness, hypotension, syncope). Drug: ATROPINE 0.5 mg IV. May need a PACEMAKER if refractory.
- SINUS TACHYCARDIA: Regular rhythm, rate >100 bpm. P waves present. Treat the UNDERLYING CAUSE (pain, fever, hypovolemia, anxiety, anemia) — NOT the rhythm itself.
- ATRIAL FIBRILLATION (AFib): IRREGULARLY IRREGULAR rhythm. NO discernible P waves (replaced by chaotic 'f' waves). Ventricular response is irregular. Most common CHRONIC dysrhythmia. Risk: THROMBUS formation in left atrium → STROKE (embolic). Management: Anticoagulation (warfarin or DOAC) + Rate control (beta-blockers, CCB, digoxin). May need rhythm control (cardioversion or amiodarone).
- ATRIAL FLUTTER: Rapid, regular atrial activity at 250–350 bpm. Classic SAWTOOTH flutter waves (F waves). Ventricular rate is regular (2:1, 3:1, or 4:1 conduction ratio). Also has stroke risk — anticoagulation needed.
- VENTRICULAR TACHYCARDIA (VT): 3 or more consecutive PVCs (premature ventricular contractions). WIDE, bizarre QRS complexes at >100 bpm. NO normal P waves associated. TWO types: (1) VT WITH PULSE but unstable → SYNCHRONIZED CARDIOVERSION; (2) PULSELESS VT → CPR + IMMEDIATE DEFIBRILLATION (treat as cardiac arrest).
- VENTRICULAR FIBRILLATION (VF): Completely chaotic, disorganized ventricular electrical activity. NO effective cardiac output. Wavy, irregular baseline — NO recognizable QRS, P waves, or T waves. LETHAL arrest rhythm. Priority: Immediate CPR + DEFIBRILLATION. Call for crash cart.
- ASYSTOLE: 'Flatline' — complete absence of electrical activity. NOT SHOCKABLE (defibrillation will not help). Treat with CPR + EPINEPHRINE IV every 3–5 minutes. Look for reversible causes (Hs and Ts).
- PVCs (Premature Ventricular Contractions): Early, wide, bizarre QRS without preceding P wave, followed by a COMPENSATORY PAUSE. Occasional PVCs in healthy adults may be normal. Concerning when: more than 6/minute, multifocal, bigeminal, R-on-T phenomenon (risk of VF).
- HEART BLOCK (3rd Degree / Complete): P waves and QRS have NO relationship. Atria and ventricles beat INDEPENDENTLY. SYMPTOMATIC — needs a PACEMAKER.
Definitions
Defibrillation
An UNSYNCHRONIZED electrical shock delivered to the heart to terminate lethal dysrhythmias (VF, pulseless VT). The shock is NOT timed to any cardiac event. It depolarizes all myocardial cells simultaneously, allowing the SA node to resume pacing.
Importance
Used ONLY for PULSELESS rhythms (VF and pulseless VT) = CARDIAC ARREST. Every minute without defibrillation decreases survival by ~10%. NLE DISTINCTION: defibrillation = NOT synchronized.
Synchronized Cardioversion
An electrical shock TIMED (synchronized) to the R wave of the QRS complex to avoid shocking during the T wave (which can trigger VF). Used for UNSTABLE but PERFUSING dysrhythmias.
Importance
Used for: Unstable AFib with rapid ventricular rate, unstable atrial flutter, stable VT with a pulse but deteriorating. The key word is SYNCHRONIZED — the machine detects the QRS and delivers the shock at the right moment. NLE DISTINCTION: cardioversion = synchronized.
Irregularly Irregular Rhythm
A rhythm where the intervals between heartbeats have NO consistent pattern — not just slightly varying, but completely unpredictable. This is the hallmark of ATRIAL FIBRILLATION.
Importance
Distinguishes AFib from all other dysrhythmias. On ECG: no visible P waves + ventricular rate that varies randomly = AFib. NLE will give a rhythm description — remember this.
Sawtooth (Flutter) Waves
The classic ECG appearance of ATRIAL FLUTTER — rapid, regular, saw-toothed deflections at 250–350/minute, caused by a re-entry circuit in the right atrium. The QRS complexes appear after every 2nd, 3rd, or 4th flutter wave.
Importance
Distinguishes atrial FLUTTER from atrial FIBRILLATION. Flutter has a pattern; AFib is chaotic. Both carry stroke risk.
Compensatory Pause
A pause in the cardiac rhythm following a premature ventricular contraction (PVC). The SA node continues at its regular rate but the early PVC 'resets' nothing, so the next normal beat occurs after a longer-than-normal pause.
Importance
Characteristic ECG feature of PVCs. After the bizarre wide QRS, there is a pause before the next normal beat.
R-on-T Phenomenon
A PVC occurring during the relative refractory period of the preceding beat — specifically on the T wave. The T wave represents a vulnerable period when a stimulus can trigger VF.
Importance
DANGEROUS — can trigger ventricular fibrillation. Must be identified and treated IMMEDIATELY. NLE may describe this as a high-risk PVC pattern.
Common mistakes
- Treating the RHYTHM on the monitor rather than the PATIENT — always assess the patient's pulse, BP, and consciousness first.
- Using DEFIBRILLATION for asystole — asystole is NOT shockable. Use CPR and epinephrine.
- Confusing defibrillation (unsynchronized, for arrest rhythms) with cardioversion (synchronized, for unstable perfusing rhythms).
- Thinking ALL bradycardia needs atropine — treat ONLY if symptomatic (hypotension, syncope, chest pain).
- Thinking sinus tachycardia is treated with antidysrhythmic drugs — treat the underlying CAUSE, not the rate.
- Missing that PULSELESS VT is treated the same as VF — CPR + immediate defibrillation.
Pacemakers: Types, Indications, and Nursing Care
Exam tips
- NLE QUESTION TYPE: 'The nurse notices pacemaker spikes on the ECG not followed by QRS complexes' = FAILURE TO CAPTURE → Assess the patient, report to physician.
- Hiccups after pacemaker insertion = LEAD DISPLACEMENT into diaphragm → Medical emergency, notify physician.
- Patient teaching priority: Check pulse DAILY; carry ID card; avoid arc welding and MRI (unless MRI-conditional); tell all health providers.
- Under RA 9173, the nurse is responsible for safe monitoring and patient teaching for pacemaker patients — this is both an independent and collaborative nursing function.
- Temporary transcutaneous pacing (external pads) = EMERGENCY bridge; transvenous = ICU setting; permanent = surgically implanted for chronic conditions.
Key points
- A pacemaker delivers electrical impulses to stimulate myocardial depolarization when the heart's natural conduction system fails.
- INDICATIONS: Symptomatic bradycardia, complete heart block (3rd degree), sick sinus syndrome, and asystole.
- TYPES: (1) TEMPORARY pacemakers — Transcutaneous (external pads on chest, used in emergencies) or Transvenous (electrode catheter via subclavian/jugular vein to right ventricle, used in ICU/CCU); (2) PERMANENT pacemakers — surgically implanted device under the skin, usually below the LEFT clavicle.
- On ECG, a pacemaker spike (vertical line) should IMMEDIATELY precede each paced QRS complex (ventricular pacing) or P wave (atrial pacing).
- FAILURE TO CAPTURE: Pacemaker spike visible on ECG but NOT followed by a QRS complex. The myocardium is not responding to the electrical stimulus. Causes: lead displacement, battery depletion, inflammation at the lead tip.
- FAILURE TO SENSE: The pacemaker does NOT detect the patient's own heartbeats and fires inappropriately (competing with the patient's own rhythm). This is dangerous — can trigger VF (R-on-T).
- FAILURE TO FIRE (OUTPUT FAILURE): No pacemaker spike when one is expected. Causes: battery failure, lead fracture, loose connections.
- After PERMANENT pacemaker implantation nursing care: Monitor incision site for signs of infection; limit movement of the IPSILATERAL arm (same side as implant) for 48–72 hours to prevent lead dislodgement; semi-Fowler's position; continuous cardiac monitoring; assess for hiccups (diaphragmatic stimulation = lead displacement into diaphragm).
- PATIENT TEACHING after permanent pacemaker: Check pulse DAILY (wrist or carotid); report pulse below the set rate, dizziness, syncope, hiccups; carry a pacemaker ID card at all times; avoid strong electromagnetic fields (arc welding, MRI unless MRI-conditional); most household appliances are SAFE (microwave ovens, cell phones if kept >15–20 cm from the device); tell all healthcare providers (dentists, surgeons) about the pacemaker; medical alert bracelet recommended.
- MRI compatibility: MOST older pacemakers are NOT MRI-compatible. Newer MRI-conditional devices are safe under specific conditions. Always verify BEFORE any MRI procedure.
Definitions
Failure to Capture
A pacemaker malfunction in which the electrical spike is visible on the ECG but is NOT followed by a QRS complex (ventricular depolarization). The heart muscle does not respond to the stimulus.
Importance
Most important pacemaker complication to recognize. The patient's heart rate may drop dangerously low. Must be reported immediately. Assess the patient for symptoms (dizziness, hypotension, syncope).
Failure to Sense
A pacemaker malfunction in which the device fails to detect (sense) the patient's own intrinsic heartbeats and fires at inappropriate times, potentially causing 'pacemaker competition' or R-on-T phenomenon.
Importance
Dangerous because firing on the T wave (R-on-T) can trigger ventricular fibrillation. Must be identified and corrected immediately.
Pacemaker Spike
A thin, vertical line visible on the ECG tracing that represents the electrical impulse delivered by the pacemaker. A pacing spike should immediately precede each paced P wave or QRS complex.
Importance
The presence of spikes followed by appropriate depolarization confirms proper pacemaker function (capture). Absence of response after a spike = failure to capture.
Common mistakes
- Restricting movement of the WRONG arm — limit the arm on the SAME SIDE as the pacemaker implant (usually left subclavicular region).
- Telling patients that ALL electromagnetic sources are dangerous — most household appliances (microwaves, cell phones) are SAFE at normal distances.
- Forgetting to check for HICCUPS after pacemaker insertion — hiccups indicate lead displacement into the diaphragm.
- Not knowing the DIFFERENCE between failure to capture, failure to sense, and failure to fire — NLE may describe an ECG tracing and ask you to identify the problem.
- Forgetting to teach the patient to carry a PACEMAKER ID CARD — especially important in the Philippine context for emergency medical situations.
Cardiac Pharmacology: Key Drugs for Heart Failure and Dysrhythmias
Exam tips
- NLE CRITICAL: Digoxin apical pulse <60 bpm = HOLD the drug + notify the physician = ALWAYS.
- Digoxin toxicity = anorexia (FIRST sign) + nausea + YELLOW-GREEN HALOS (visual disturbances) + bradycardia + dysrhythmias → Antidote: DIGOXIN IMMUNE FAB.
- HYPOKALEMIA + DIGOXIN = DANGER — monitor K+ in ALL patients on both loop diuretics AND digoxin.
- DIURETIC MEMORY AID: Loop and Thiazide = LOSE Potassium (hypokalemia). Spironolactone = KEEPS Potassium (hyperkalemia). 'K-SPARING = K-KEEPING'.
- ACE inhibitor cough → switch to ARB. ACE inhibitor angioedema → STOP IMMEDIATELY, switch to ARB.
- Beta-blockers in HF: 'START LOW, GO SLOW' — never start at high doses; never stop abruptly.
- Amiodarone side effects = PATTCH: Pulmonary toxicity, Arrhythmias (pro-arrhythmic), Thyroid dysfunction, Torsades (QT prolongation), Corneal deposits, Hepatotoxicity/photosensitivity.
Key points
- DIGOXIN (Cardiac Glycoside): Positive INOTROPE (increases contractility) + Negative CHRONOTROPE (slows HR). Uses: HF with reduced EF; rate control in AFib.
- DIGOXIN THERAPEUTIC LEVEL: 0.5–2 ng/mL. Toxicity occurs >2 ng/mL.
- BEFORE EVERY DOSE of digoxin: Take APICAL PULSE for ONE FULL MINUTE. HOLD and notify the physician if HR <60 bpm in adults (or <90–110 in infants/children).
- DIGOXIN TOXICITY SIGNS: Anorexia (FIRST sign), nausea, vomiting, VISUAL DISTURBANCES (yellow-green halos around lights, blurred vision), bradycardia, and dysrhythmias (PVCs, heart block).
- HYPOKALEMIA POTENTIATES DIGOXIN TOXICITY — when potassium is low, digoxin binds more avidly to the Na-K-ATPase pump → increased toxicity risk. Monitor K+ closely especially in patients on loop diuretics.
- ANTIDOTE for digoxin toxicity: DIGOXIN IMMUNE FAB (Digibind).
- LOOP DIURETICS (Furosemide/Lasix): Most potent; used for acute and chronic fluid overload. Side effects: HYPOKALEMIA, hyponatremia, ototoxicity (with rapid IV push or high doses), dehydration. Monitor K+ and urine output. Give IV furosemide SLOWLY to prevent ototoxicity.
- THIAZIDE DIURETICS (Hydrochlorothiazide/HCTZ): For mild HF and hypertension. Also cause HYPOKALEMIA. Less potent than loop diuretics.
- POTASSIUM-SPARING DIURETICS (Spironolactone/Aldactone): Aldosterone antagonist. Improves HF SURVIVAL (RALES trial). Risk: HYPERKALEMIA. Avoid KCl supplements and salt substitutes (potassium chloride) in patients on spironolactone. Monitor K+.
- ACE INHIBITORS (Enalapril, Lisinopril, Captopril): Reduce afterload and prevent remodeling. Side effects: Dry persistent cough (most common), HYPERKALEMIA, hypotension (first-dose), ANGIOEDEMA (rare but dangerous — discontinue immediately). Monitor K+ and BUN/creatinine.
- ARBs (Losartan, Valsartan): Same mechanism as ACE-I but block the Ang-II receptor. Alternative when ACE-I causes cough. Same hyperkalemia risk. NO cough side effect.
- BETA-BLOCKERS (Carvedilol, Metoprolol succinate, Bisoprolol): Improve long-term HF SURVIVAL. Start at low doses, titrate slowly. Side effects: Bradycardia, hypotension, fatigue, bronchospasm (avoid in asthma). HOLD if HR <60 bpm or BP is low. NEVER STOP ABRUPTLY — rebound tachycardia and angina may occur.
- NITRATES (Isosorbide Dinitrate, Nitroglycerin): Venodilators — reduce PRELOAD. Used in HF and angina. Combined with hydralazine, they improve HF survival in ACE-I intolerant patients. Side effects: HEADACHE (most common), orthostatic hypotension. Hold if SBP <90 mmHg. Tolerance develops with continuous use — provide nitrate-free interval.
- HYDRALAZINE (Apresoline): Arterial vasodilator — reduces AFTERLOAD. Used with nitrates in HF. Side effect: Reflex tachycardia, lupus-like syndrome with long-term use.
- AMIODARONE: Broad-spectrum antidysrhythmic used for AFib, VT, VF. MONITOR for: Pulmonary toxicity (most serious), thyroid dysfunction (both hypo and hyperthyroidism), hepatotoxicity, corneal microdeposits (vision changes), skin photosensitivity, QT prolongation. Sun protection teaching required.
- ANTICOAGULANTS (Warfarin, DOACs — Apixaban, Rivaroxaban, Dabigatran): Required in AFib to prevent EMBOLIC STROKE. Warfarin: Monitor INR (target 2.0–3.0); many drug and food interactions; antidote = Vitamin K (or FFP for emergencies). DOACs: Fewer interactions, no routine INR monitoring needed.
- IV POSITIVE INOTROPES (Dobutamine, Milrinone): Used in ACUTE DECOMPENSATED HF in ICU/CCU. Improve contractility and cardiac output. Given IV drip, require continuous cardiac monitoring. Dobutamine: beta-1 agonist. Milrinone: phosphodiesterase inhibitor.
- NEVER combine rate-slowing drugs (e.g., digoxin + beta-blocker, or digoxin + diltiazem) without CLOSE monitoring for dangerous bradycardia.
Definitions
Positive Inotrope
A drug that increases the FORCE of myocardial contraction (contractility), thereby improving stroke volume and cardiac output. Examples: digoxin, dobutamine, milrinone.
Importance
Key pharmacodynamic term in HF pharmacology. Positive inotropy = stronger heartbeat. Digoxin is the classic oral positive inotrope tested in NLE.
Negative Chronotrope
A drug that DECREASES the heart RATE by slowing the rate of SA node impulse generation. Examples: digoxin, beta-blockers, calcium channel blockers (verapamil, diltiazem).
Importance
Digoxin is BOTH a positive inotrope AND a negative chronotrope — this dual action makes it useful in HF (stronger pumping) and in AFib (rate control).
Angioedema
Rapid, potentially life-threatening swelling of the face, lips, tongue, throat, and larynx. A rare but serious adverse effect of ACE inhibitors. May cause upper airway obstruction.
Importance
DISCONTINUE ACE inhibitor IMMEDIATELY if angioedema occurs. This is a medical emergency. Switch to an ARB (which does NOT cause angioedema). Frequently tested as a NLE safety question.
Nitrate Tolerance
A reduction in the effectiveness of nitrates with continuous use, caused by depletion of vascular sulfhydryl groups. Prevented by providing a daily nitrate-free interval (usually 8–12 hours, often overnight).
Importance
Nurses must teach patients about the nitrate-free interval — continuous 24-hour use of nitrates leads to loss of effectiveness.
INR (International Normalized Ratio)
A standardized measure of blood clotting time used to monitor warfarin therapy. Target INR for AFib anticoagulation is 2.0–3.0.
Importance
INR <2 = undertreated (stroke risk); INR >3 = overtreated (bleeding risk). Monitor regularly. Vitamin K-rich foods (kangkong, ampalaya, malunggay) can affect INR — teach consistency in intake.
Common mistakes
- Forgetting to take the APICAL PULSE (not radial) before digoxin — apical pulse is used because it accounts for pulse deficit.
- Holding digoxin based on RADIAL pulse instead of the APICAL pulse — use the APICAL pulse over the apex of the heart.
- Not connecting hypokalemia (from loop diuretics) to increased digoxin toxicity risk — these two are frequently combined in NLE scenarios.
- Giving potassium supplements or salt substitutes to a patient on SPIRONOLACTONE — this can cause life-threatening hyperkalemia.
- Stopping beta-blockers ABRUPTLY — this causes rebound sympathetic activation: sudden tachycardia, hypertension, and potential MI or angina.
- Giving nitrates to a patient with SBP <90 mmHg — will cause severe hypotension.
- Not knowing the antidote for digoxin toxicity = DIGOXIN IMMUNE FAB (Digibind) — this is a classic NLE question.
Connections
- Heart failure directly connects to FLUID AND ELECTROLYTE BALANCE — HF causes fluid retention (Excess Fluid Volume NANDA diagnosis); diuretic treatment causes electrolyte imbalances (especially hypokalemia), which in turn affect CARDIAC DYSRHYTHMIAS and DIGOXIN SAFETY.
- The RAAS system (studied in Anatomy and Physiology) is central to HF pathophysiology AND pharmacology — ACE inhibitors, ARBs, and spironolactone all target RAAS, connecting cardiovascular nursing to endocrine physiology.
- CARDIAC DYSRHYTHMIAS connect to ELECTROLYTE IMBALANCES — hypokalemia (low K+) can cause VT and VF; hyperkalemia can cause bradycardia and heart block; hypomagnesemia contributes to ventricular dysrhythmias. Always check electrolytes in dysrhythmia management.
- ACUTE PULMONARY EDEMA connects to NCM 103 (Respiratory Nursing) — impaired gas exchange is the priority nursing diagnosis, requiring oxygen therapy, positioning, and respiratory assessment skills common to both cardiovascular and respiratory nursing.
- ANTICOAGULATION in AFib connects to HEMATOLOGIC NURSING — warfarin monitoring (INR), bleeding precautions, and the risks of anticoagulation are shared across multiple conditions (DVT, pulmonary embolism, prosthetic heart valves).
- DIGOXIN PHARMACOLOGY connects to PEDIATRIC NURSING (NCM 105) — digoxin is also used in pediatric HF (e.g., in congenital heart disease); the hold parameters differ (hold if HR <90–110 in infants), linking cardiovascular pharmacology across the lifespan.
- The NURSING PROCESS in HF care connects to the STANDARDS OF NURSING PRACTICE under RA 9173 — assessment, diagnosis (NANDA), planning, intervention, and evaluation form the legal and professional framework for all nursing care in the Philippines.
- Pacemaker care connects to PERIOPERATIVE NURSING — pacemaker implantation is a surgical procedure; post-implantation nursing care involves surgical site monitoring, activity restrictions, and patient teaching, which overlap with post-operative nursing principles.
- STROKE PREVENTION in AFib connects to NEUROLOGICAL NURSING (NCM 104) — understanding cardioembolic stroke (from AFib) links cardiovascular and neurological nursing, and anticoagulation management is a shared topic.
- DOH PHILPEN PROGRAM — connects HF nursing to PUBLIC HEALTH NURSING (NCM 107). Hypertension control at barangay health centers and rural health units (RHUs) is the first line of defense against HF development, linking hospital-based cardiovascular nursing to community health nursing.
Quick review questions
A nurse is caring for a patient admitted for heart failure. The patient reports sleeping with 3 pillows and waking up at night gasping for air. Which side of the heart is primarily failing, and what are these symptoms called?
Answer
LEFT-sided heart failure. The symptoms are ORTHOPNEA (needing multiple pillows to breathe when lying flat) and PAROXYSMAL NOCTURNAL DYSPNEA (PND — sudden awakening from sleep with severe dyspnea).
Left HF causes blood to back up into the pulmonary circulation. Lying flat (supine) redistributes fluid from dependent areas into the lungs, causing dyspnea. Remember: LEFT = LUNGS. Orthopnea and PND are hallmark signs of left HF. The priority nursing intervention is positioning the patient in HIGH FOWLER'S position.
A nurse assesses a patient with right-sided heart failure. Which of the following findings should the nurse expect? (A) Crackles and pink frothy sputum. (B) Peripheral edema, JVD, and hepatomegaly. (C) S3 gallop and orthopnea. (D) Pink frothy sputum and tachycardia.
Answer
(B) Peripheral edema, JVD, and hepatomegaly.
RIGHT-sided HF causes blood to back up into the SYSTEMIC venous circulation — think 'Right = Rest of the body.' This produces: peripheral/dependent edema, jugular venous distention (JVD), hepatomegaly, ascites, and GI symptoms. Options A, C, and D are LEFT HF signs (pulmonary congestion = lungs).
A patient with acute pulmonary edema arrives at the emergency department, severely dyspneic with pink frothy sputum. What is the PRIORITY nursing intervention?
Answer
Position the patient in HIGH FOWLER'S position (90°) with LEGS DEPENDENT (feet dangling off the side of the bed), and administer high-flow oxygen.
Positioning in high Fowler's with legs dependent is the FIRST priority — it uses gravity to reduce venous return (preload) to the overloaded pulmonary circulation, improving breathing immediately. Remember LMNOP: Legs dependent → Morphine → Nitrates → Oxygen → Pump (furosemide IV). Based on Maslow's hierarchy, oxygenation and breathing are the highest physiologic priorities.
A nurse is about to administer digoxin 0.25 mg PO to a patient with heart failure. The patient's apical pulse is 58 bpm. What is the nurse's PRIORITY action?
Answer
HOLD the digoxin and NOTIFY the physician. Do NOT administer the dose.
The standard rule is: TAKE the apical pulse for ONE FULL MINUTE before every digoxin dose. HOLD if the HR is <60 bpm in adults. An apical pulse of 58 bpm is below the threshold — administering digoxin (a negative chronotrope) could further slow the heart rate and cause dangerous bradycardia or heart block. Document the held dose and the physician notification.
A patient on digoxin and furosemide reports seeing 'yellow-green halos around lights,' has nausea, and has a heart rate of 48 bpm. The serum digoxin level is 2.8 ng/mL. What condition is occurring and what is the antidote?
Answer
DIGOXIN TOXICITY. The antidote is DIGOXIN IMMUNE FAB (Digibind).
Classic signs of digoxin toxicity: anorexia/nausea (GI — first signs), YELLOW-GREEN VISUAL HALOS (pathognomonic), bradycardia, and dysrhythmias. Serum level >2 ng/mL confirms toxicity. Furosemide causes hypokalemia, which POTENTIATES digoxin toxicity (low K+ allows more digoxin binding). The ANTIDOTE is Digoxin Immune Fab (Digibind) — it binds and inactivates digoxin in the bloodstream. This is a high-yield NLE question.
The nurse is monitoring a patient's cardiac rhythm and notes a completely irregular ventricular rate with no identifiable P waves. What dysrhythmia does this represent, and what is the most critical complication to prevent?
Answer
ATRIAL FIBRILLATION (AFib). The most critical complication is THROMBOEMBOLIC STROKE.
AFib is characterized by: IRREGULARLY IRREGULAR rhythm + NO discernible P waves (chaotic 'f' waves instead) + irregular QRS response. Chaotic atrial activity causes blood stasis in the left atrial appendage → THROMBUS formation → clot travels to the brain → EMBOLIC STROKE. Therefore, ANTICOAGULATION (warfarin with INR 2–3, or a DOAC) is MANDATORY in most AFib patients to prevent stroke. Rate control uses beta-blockers, calcium channel blockers, or digoxin.
A patient goes into ventricular fibrillation. The nurse confirms the rhythm on the monitor and finds no pulse. What is the IMMEDIATE priority action?
Answer
Start CPR IMMEDIATELY and prepare for DEFIBRILLATION (unsynchronized electrical shock). Call for the crash cart.
VF = completely chaotic ventricular electrical activity = NO cardiac output = CARDIAC ARREST = LETHAL rhythm. Immediate actions: (1) Call for help / activate code; (2) Start CPR; (3) Attach AED/defibrillator; (4) Deliver UNSYNCHRONIZED shock (defibrillation) as soon as possible. Do NOT attempt synchronized cardioversion for VF — it requires a detectable R wave. Remember: every minute without defibrillation reduces survival by ~10%.
Why should loop diuretics (furosemide) and thiazide diuretics (HCTZ) be of particular concern in a patient who is also taking digoxin?
Answer
Loop and thiazide diuretics cause HYPOKALEMIA (low serum potassium). Hypokalemia POTENTIATES (increases) digoxin toxicity, raising the risk of dangerous dysrhythmias even at therapeutic digoxin levels.
Mechanism: Digoxin works by inhibiting the Na-K-ATPase pump. When K+ is low (hypokalemia), digoxin competes more effectively with potassium for the pump, leading to increased cellular digoxin effects and toxicity. The nurse must MONITOR serum potassium closely in patients on both digoxin AND diuretics. Potassium supplementation or use of potassium-sparing diuretics (spironolactone) may be prescribed to protect against this interaction.
A patient with a newly implanted permanent pacemaker reports persistent hiccups. What does this indicate, and what is the nurse's priority action?
Answer
Persistent hiccups after pacemaker implantation indicate LEAD DISPLACEMENT — the pacemaker lead has migrated and is stimulating the DIAPHRAGM instead of (or in addition to) the heart. Priority action: NOTIFY the physician IMMEDIATELY.
When the pacing lead displaces downward toward the diaphragm, electrical impulses stimulate the diaphragm causing rhythmic hiccups that correspond with pacemaker spikes. This is a complication requiring immediate repositioning of the lead. The nurse should also assess for failure to capture (pacing spikes without QRS complexes on the ECG) and hemodynamic instability.
A nurse is teaching an HF patient about daily monitoring at home. What specific weight change should the patient immediately report to the physician?
Answer
Report a weight gain of 1 kg (approximately 2 lbs) in ONE DAY, or 2.5 kg (approximately 5 lbs) in ONE WEEK.
Daily weight monitoring is the CORNERSTONE of HF self-management because rapid weight gain reflects fluid retention (decompensation) BEFORE clinical symptoms (severe edema, dyspnea) worsen. Teach: Weigh every morning, at the SAME time (after first void, before breakfast), wearing the SAME clothing, on the SAME scale. These specific thresholds (1 kg/day or 2.5 kg/week) are frequently tested in NLE. This is a primary prevention strategy aligned with the DOH's NCD management goals under the Philippine healthcare system.
Diagrams
Heart Failure and Cardiac Dysrhythmias: Chapter Overview Mind Map
This comprehensive mind map provides a visual overview of the entire chapter, showing the relationships between heart failure (left and right-sided), acute pulmonary edema, cardiac dysrhythmias, pacemakers, and key pharmacology. Use this as a quick reference to see how all topics connect. Each main branch represents a major exam topic area.
Priority Nursing Management of Acute Pulmonary Edema (LMNOP Protocol)
This flowchart shows the step-by-step priority nursing management of acute pulmonary edema using the LMNOP framework. Follow the arrows from initial assessment through positioning, oxygenation, IV access, medications, and ongoing monitoring. Note the critical decision point regarding blood pressure before administering nitrates or morphine. This sequential approach reflects the nursing process and Maslow-based prioritization.
Cardiac Dysrhythmia Recognition and Management Algorithm
This decision-tree flowchart guides the nurse through the systematic assessment and management of cardiac dysrhythmias. Starting with the critical question of whether the patient has a pulse, the algorithm differentiates between arrest rhythms (VF, pulseless VT, asystole, PEA) and perfusing but unstable or stable dysrhythmias. Key NLE distinctions are highlighted: defibrillation (unsynchronized, for pulseless arrest) vs. cardioversion (synchronized, for unstable perfusing rhythms), and the treatment of specific rhythms.
Safe Digoxin Administration: Pre-Administration Safety Checklist
This safety flowchart details the complete pre-administration assessment protocol for digoxin — one of the most frequently tested medication safety topics in the NLE. The three critical checkpoints are: (1) serum digoxin level (0.5–2 ng/mL), (2) serum potassium level (≥3.5 mEq/L), and (3) apical pulse (≥60 bpm). Any parameter outside the safe range requires holding the medication and notifying the physician. The flowchart also includes patient teaching points.
Diuretics in Heart Failure: Potassium Effects Summary
This pie chart provides a quick visual summary of how the three major diuretic classes used in heart failure management differ in their potassium effects. Loop diuretics (furosemide) and thiazides LOSE potassium (hypokalemia), while spironolactone (potassium-sparing) KEEPS potassium (hyperkalemia risk). This distinction is critical for NLE because hypokalemia increases digoxin toxicity risk, and hyperkalemia is dangerous in patients on ACE inhibitors or ARBs. The chart also notes that combination therapy (loop + spironolactone) is commonly used in clinical practice.
Progression of Heart Failure: From Compensation to Decompensation
This state diagram illustrates the progression of heart failure from normal cardiac function through the stages of compensation, chronic failure, acute decompensation, pulmonary edema, and cardiogenic shock. It shows how the body's compensatory mechanisms (SNS, RAAS, hypertrophy) initially help but eventually become maladaptive, and how HF drugs interrupt this cycle. The diagram also shows the triggers for decompensation and the emergency management pathway. Understanding this progression is essential for NLE clinical reasoning questions.
Exam strategy
For the NLE, approach Heart Failure and Dysrhythmia questions using these strategies: (1) PRIORITY-BASED THINKING: Always apply Maslow's Hierarchy — airway, breathing, and circulation (ABCs) come FIRST. In pulmonary edema scenarios, positioning (high Fowler's) is always the first answer. (2) PATIENT vs. RHYTHM: When a dysrhythmia scenario appears, check if the patient has a PULSE and is HEMODYNAMICALLY STABLE before selecting interventions — treat the patient, not just the monitor. (3) MEMORY AIDS: Use LEFT=LUNGS and RIGHT=REST for HF sides; LMNOP for pulmonary edema management; PATTCH for amiodarone toxicity; K-SPARING=K-KEEPING for spironolactone. (4) DRUG SAFETY: For digoxin questions — always check APICAL PULSE first, know the therapeutic level (0.5–2 ng/mL), know toxicity signs (yellow-green halos), know the antidote (Digibind), and know the potassium connection. For beta-blockers — hold if HR <60, never stop abruptly. (5) SHOCKABLE vs. NON-SHOCKABLE rhythms: VF and pulseless VT = SHOCK (defibrillate); Asystole and PEA = DO NOT SHOCK (CPR + epinephrine). (6) SYNCHRONIZED vs. UNSYNCHRONIZED: Cardioversion = SYNCHRONIZED (for unstable perfusing rhythms); Defibrillation = UNSYNCHRONIZED (for pulseless arrest rhythms). (7) ELIMINATION STRATEGY: If two NLE answer options seem similar, look for the one that addresses SAFETY and PHYSIOLOGIC NEEDS first (Maslow). (8) PHILIPPINE CONTEXT: Reference DOH PhilPEN for NCD/HTN prevention at primary care level; reference RA 9173 for scope of nursing practice questions; know that under RA 9173, nurses are legally accountable for medication administration safety including pulse checks before cardiac drugs. (9) LABS TO KNOW: BNP >100 pg/mL = HF; Digoxin therapeutic 0.5–2 ng/mL; INR target for AFib anticoagulation = 2.0–3.0; Potassium normal = 3.5–5.0 mEq/L (hypokalemia <3.5; hyperkalemia >5.0). (10) TIME MANAGEMENT: In the NLE, do not spend more than 1 minute per question. If unsure, eliminate clearly wrong answers, apply nursing process (assessment before intervention), and select the safest, most physiologically sound option.