NLE Cardiovascular Nursing — Heart Failure and Cardiac DysrhythmiasDetailed Explanation

Pathophysiology of Heart Failure and Compensatory Mechanisms

Heart failure (HF) is a clinical syndrome in which the heart cannot pump sufficient blood to meet the body's metabolic demands. Think of the heart as a water pump: if the pump weakens, water (blood) backs up behind it. HF is usually the end result of conditions that damage or overwork the myocardium — coronary artery disease (CAD), myocardial infarction (MI), hypertension, valvular disease, and cardiomyopathy are the most common causes in the Philippine setting. When the heart begins to fail, three major compensatory mechanisms activate: 1. SYMPATHETIC NERVOUS SYSTEM (SNS) ACTIVATION: The body perceives low cardiac output as a threat. The SNS releases catecholamines (epinephrine, norepinephrine), which increase heart rate (positive chronotropy) and force of contraction (positive inotropy). This is why HF patients are often tachycardic. 2. RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM (RAAS) ACTIVATION: Reduced renal perfusion triggers renin release → angiotensin II (vasoconstrictor) → aldosterone release → sodium and water retention. This increases blood volume (preload) to fill the failing heart. This is why HF patients retain fluid and become edematous. 3. VENTRICULAR HYPERTROPHY AND DILATION: The heart muscle thickens (hypertrophy) and the chambers enlarge (dilation) to accommodate more blood and pump harder. The Problem: These compensatory mechanisms are initially helpful but become MALADAPTIVE over time. Increased afterload (from vasoconstriction), fluid overload, and ventricular remodeling worsen the failure in a vicious cycle. This is the scientific basis for treating HF with drugs that BLOCK these systems — ACE inhibitors and ARBs block RAAS; beta-blockers block SNS; spironolactone blocks aldosterone. Key Classification: - SYSTOLIC HF (HF with reduced ejection fraction, HFrEF): The ventricle cannot contract forcefully enough. Ejection fraction (EF) is below 40%. - DIASTOLIC HF (HF with preserved ejection fraction, HFpEF): The ventricle cannot relax and fill properly. EF is normal (above 50%) but filling is impaired.

Left-Sided Heart Failure: Manifestations and Nursing Care

LEFT-SIDED HEART FAILURE = LUNG PROBLEMS. This is the single most important memory trick for the NLE. When the left ventricle (LV) fails to pump blood forward into the aorta and systemic circulation, blood backs up into the PULMONARY CIRCULATION — the lungs. This is called PULMONARY CONGESTION or PULMONARY VENOUS HYPERTENSION. Picture a traffic jam on the expressway (aorta is blocked → cars pile up on the on-ramp → the on-ramp is your pulmonary veins → the lungs get congested). KEY MANIFESTATIONS OF LEFT-SIDED HF: 1. DYSPNEA (difficulty breathing): The hallmark symptom. Fluid in the lungs impairs gas exchange. 2. ORTHOPNEA: Breathlessness when lying flat. When supine, venous return to the heart increases, worsening pulmonary congestion. Patients sleep with 2–3 pillows (ask how many pillows they use — this is a clinical assessment point). 3. PAROXYSMAL NOCTURNAL DYSPNEA (PND): Sudden awakening from sleep with severe shortness of breath. Edema from the legs redistributes to the lungs when the patient lies down. 4. CRACKLES (RALES): Fine, wet sounds on lung auscultation — fluid in the alveoli. 5. FROTHY, PINK (BLOOD-TINGED) SPUTUM: In severe cases (pulmonary edema), alveolar flooding causes blood-tinged frothy sputum. 6. S3 GALLOP HEART SOUND: An extra heart sound after S2, heard at the apex — called the 'ventricular gallop'; heard in fluid-overloaded ventricles. 7. FATIGUE AND WEAKNESS: Reduced cardiac output means less oxygen delivery to tissues. 8. TACHYCARDIA: Compensatory SNS response. 9. RESTLESSNESS AND ANXIETY: From cerebral hypoxia. NURSING DIAGNOSES (NANDA): - Impaired Gas Exchange r/t pulmonary congestion (PRIORITY — airway and breathing = Maslow's physiologic needs, first level) - Activity Intolerance r/t decreased cardiac output - Fluid Volume Excess r/t sodium and water retention - Anxiety r/t difficulty breathing NURSING INTERVENTIONS: - Position: Semi-Fowler's to High Fowler's to ease breathing and reduce venous return - Administer oxygen as prescribed - Auscultate lung sounds every 2–4 hours - Monitor oxygen saturation continuously - Administer diuretics as ordered - Daily weights (same time, same scale, same clothing) - Strict I&O monitoring - Restrict sodium and fluids as ordered - Maintain a calm environment to reduce anxiety

Right-Sided Heart Failure: Manifestations and Nursing Care

RIGHT-SIDED HEART FAILURE = SYSTEMIC (REST OF THE BODY) PROBLEMS. When the right ventricle (RV) fails to pump blood forward into the pulmonary artery, blood backs up into the SYSTEMIC VENOUS CIRCULATION. Think of it as a backup in the veins of the body — the liver, legs, abdomen, and gastrointestinal tract all become congested. THE MOST COMMON CAUSE OF RIGHT HF IS LEFT HF. As left HF progresses, pulmonary hypertension develops, and the right ventricle, which pumps against this increased resistance, eventually fails. This is called BIVENTRICULAR FAILURE. Other causes of isolated right HF include: cor pulmonale (from chronic lung disease like COPD or pulmonary TB — very relevant in the Philippine setting), pulmonary embolism, and right-sided MI. KEY MANIFESTATIONS OF RIGHT-SIDED HF: 1. PERIPHERAL AND DEPENDENT EDEMA: Pitting edema of the ankles, feet, and legs (in ambulatory patients) or the sacrum (in bedridden patients). This is the HALLMARK of right HF. 2. JUGULAR VENOUS DISTENTION (JVD): Engorgement of the jugular veins due to increased venous pressure. Assess with patient at 45-degree angle — JVD is abnormal if > 3–4 cm above the sternal angle. 3. HEPATOMEGALY: Liver congestion causes enlargement and right upper quadrant (RUQ) tenderness. 4. ASCITES: Fluid accumulation in the peritoneal cavity from portal hypertension. 5. ANOREXIA AND NAUSEA: From GI congestion and hepatomegaly. 6. WEIGHT GAIN: From fluid retention — this is the key monitoring parameter. 7. SPLENOMEGALY: Spleen congestion. NURSING DIAGNOSES (NANDA): - Excess Fluid Volume r/t sodium and water retention secondary to right HF - Activity Intolerance r/t decreased cardiac output - Impaired Skin Integrity r/t edema (risk for pressure ulcers) - Imbalanced Nutrition: Less than Body Requirements r/t anorexia and nausea NURSING INTERVENTIONS: - Daily weight monitoring (same time, same scale, same clothing) — REPORT 1 kg gain in 1 day or 2.5 kg in 1 week - Strict I&O monitoring - Measure abdominal girth daily if ascites is present - Assess JVD at 45-degree angle - Skin care: elevate edematous legs, reposition every 2 hours, use pressure-relieving mattresses - Sodium restriction (usually 2 g/day) - Fluid restriction as ordered - Administer diuretics as prescribed - Monitor electrolytes, especially potassium

Acute Pulmonary Edema: Emergency Management (LMNOP)

Acute pulmonary edema is a LIFE-THREATENING MEDICAL EMERGENCY in which fluid rapidly floods the alveoli, usually from acute decompensated left-sided heart failure. It requires IMMEDIATE nursing action. THINK OF IT THIS WAY: The alveoli are tiny air sacs. In acute pulmonary edema, they fill with fluid like a soaked sponge — no air can enter, oxygen cannot reach the blood, and the patient is essentially drowning in their own fluid. CLINICAL PICTURE: - SEVERE dyspnea (patient looks terrified, cannot speak in full sentences) - EXTREME anxiety and agitation - PINK FROTHY SPUTUM (hallmark — blood-tinged fluid from broken capillaries) - Crackles throughout ALL lung fields (not just bases) - Tachypnea (rapid breathing) - Tachycardia - Hypoxia (SpO2 dropping rapidly) - Diaphoresis (cold, clammy skin) - Cyanosis in severe cases PRIORITY NURSING INTERVENTIONS — THE LMNOP MNEMONIC: L — POSITION (High Fowler's with legs DEPENDENT): Sitting upright with legs hanging down reduces venous return to the heart, decreasing preload and the amount of blood going to the lungs. THIS IS THE FIRST PRIORITY ACTION because it is fast, non-pharmacological, and immediately reduces pulmonary congestion. M — MORPHINE IV: Reduces anxiety (decreases the work of breathing from anxiety-driven tachypnea), reduces preload (venodilation), and reduces afterload. Note: Use with caution in patients with respiratory depression. N — NITRATES (nitroglycerin): Potent venodilators that reduce preload rapidly. Also dilate the coronary arteries. Given sublingually or IV. Hold if systolic BP is low. O — OXYGEN (high-flow): Administer high-flow oxygen via face mask or prepare for noninvasive positive pressure ventilation (BiPAP/CPAP). Target SpO2 > 94%. P — DIURETICS (Loop diuretics — furosemide IV): Promote rapid diuresis to remove excess fluid. IV furosemide works within minutes (also has an immediate venodilatory effect even before diuresis begins). Give slowly to prevent ototoxicity. CONTINUOUS MONITORING: - SpO2 every 15 minutes or continuous pulse oximetry - Respiratory rate and effort - Strict I&O (expect large urine output after furosemide) - Blood pressure (especially before nitrates and morphine) - Prepare for possible endotracheal intubation if the patient continues to deteriorate NURSING DIAGNOSIS (PRIORITY): Impaired Gas Exchange r/t alveolar flooding secondary to acute pulmonary edema (Maslow: physiologic — oxygenation is #1)

Cardiac Dysrhythmias: Recognition and Management

Cardiac dysrhythmias are disturbances in the rate, rhythm, or conduction of the heartbeat. For the NLE, you need to (1) recognize each rhythm, (2) know if it is lethal, (3) know what drug or intervention treats it, and (4) ALWAYS assess the patient's hemodynamic status — a rhythm only matters if it compromises cardiac output. THE GOLDEN RULE: 'Treat the patient, not the monitor.' A rhythm that looks alarming but produces no symptoms may be observed; a rhythm causing hypotension, chest pain, or altered consciousness requires IMMEDIATE intervention. --- COMMON DYSRHYTHMIAS --- 1. SINUS BRADYCARDIA - Rate: < 60 bpm; Regular rhythm; Normal P waves; Normal QRS - Treat ONLY if symptomatic (dizziness, hypotension, syncope, chest pain) - DRUG: Atropine (blocks vagal tone, increases HR) - If atropine fails: transcutaneous pacing 2. SINUS TACHYCARDIA - Rate: > 100 bpm; Regular; Normal P, QRS - It is a COMPENSATORY RESPONSE (fever, pain, anxiety, hypovolemia, anemia, HF) - TREAT THE UNDERLYING CAUSE — do not just treat the rate 3. ATRIAL FIBRILLATION (AFib) - MOST COMMON chronic cardiac dysrhythmia - Key ECG features: IRREGULARLY IRREGULAR rhythm; NO discernible P waves (replaced by fine fibrillatory waves); Irregular R-R intervals - Pathophysiology: Chaotic atrial electrical activity → loss of atrial 'kick' (atrial contraction contributes 20–30% of ventricular filling) → blood pools in the atria (especially the left atrial appendage) → THROMBUS FORMATION → EMBOLIC STROKE - MANAGEMENT: * RATE CONTROL: Beta-blockers, calcium channel blockers (diltiazem, verapamil), or digoxin * RHYTHM CONTROL: Amiodarone, synchronized cardioversion * ANTICOAGULATION (PRIORITY for stroke prevention): Warfarin (target INR 2–3) or direct oral anticoagulants (DOACs) like rivaroxaban, apixaban - NURSING PRIORITY: Anticoagulation to prevent embolic stroke — monitor INR for warfarin, teach bleeding precautions 4. ATRIAL FLUTTER - Rapid, regular atrial activity at 250–350 bpm - Key ECG feature: SAWTOOTH flutter waves (F waves) - Ventricular rate depends on conduction ratio (2:1, 3:1, 4:1) - Management: Similar to AFib (rate control, cardioversion, anticoagulation) 5. VENTRICULAR TACHYCARDIA (VT) - Rate: 100–250 bpm; Regular; WIDE QRS (> 0.12 sec); No normal P waves - Three or more consecutive premature ventricular contractions (PVCs) - TWO SCENARIOS: * VT WITH PULSE: If hemodynamically unstable → SYNCHRONIZED CARDIOVERSION; If stable → antiarrhythmics (amiodarone) * PULSELESS VT: CARDIAC ARREST RHYTHM → IMMEDIATE CPR + DEFIBRILLATION (unsynchronized) 6. VENTRICULAR FIBRILLATION (VF) - LETHAL ARREST RHYTHM — chaotic, disorganized ventricular activity with NO effective cardiac output - ECG: Chaotic, irregular waves with no identifiable QRS complexes - TREATMENT: IMMEDIATE CPR + DEFIBRILLATION (unsynchronized shock) — the ONLY effective treatment - Every minute without defibrillation decreases survival by ~10% 7. ASYSTOLE ('FLATLINE') - Complete absence of electrical activity — no P waves, no QRS, straight line on ECG - NOT SHOCKABLE — defibrillation will not work - TREATMENT: CPR + Epinephrine IV (every 3–5 minutes) + identify and treat reversible causes (the 'Hs and Ts') --- DEFIBRILLATION vs. SYNCHRONIZED CARDIOVERSION --- - DEFIBRILLATION: UNSYNCHRONIZED shock; used for PULSELESS VT and VF (arrest rhythms); no timing with QRS needed; IMMEDIATE - SYNCHRONIZED CARDIOVERSION: Timed shock that avoids the T wave (to prevent inducing VF); used for UNSTABLE rhythms WITH a pulse (unstable AFib with rapid ventricular response, stable VT with pulse but deteriorating, atrial flutter)

Pacemakers: Nursing Care and Patient Teaching

A pacemaker is an electronic device that delivers electrical impulses to stimulate the myocardium when the heart's natural conduction system fails to maintain an adequate rate or rhythm. It is indicated for symptomatic bradycardia, high-degree heart block, asystole, and certain cases of HF (cardiac resynchronization therapy). TYPES OF PACEMAKERS: 1. TEMPORARY PACEMAKERS: - TRANSCUTANEOUS (External): Pacing electrodes placed on the skin (anterior and posterior). Used in emergencies. Uncomfortable — may require sedation. - TRANSVENOUS: A pacing catheter inserted via the subclavian or jugular vein, advanced to the right ventricle. Used for temporary bridge therapy. 2. PERMANENT PACEMAKERS: - Surgically implanted device (pulse generator + leads) — placed in a subcutaneous pocket, usually in the left or right upper chest below the clavicle. - Leads threaded through subclavian/cephalic vein into the right atrium and/or ventricle. ECG MONITORING FOR PACEMAKER FUNCTION: - NORMAL PACEMAKER: A PACING SPIKE followed immediately by a P wave (atrial pacing) or QRS complex (ventricular pacing). - FAILURE TO CAPTURE: A pacing spike is seen on the ECG but is NOT followed by a P wave or QRS complex. The myocardium is not responding to the stimulus. Causes: lead displacement, low output, exit block, myocardial fibrosis. - FAILURE TO SENSE: The pacemaker fires even when the patient's own heartbeat is occurring (competing with the native rhythm). Causes: lead displacement, oversensing or undersensing. - FAILURE TO PACE: No pacing spikes are visible when they should be present. POST-IMPLANTATION NURSING CARE: 1. ACTIVITY RESTRICTION: Limit movement of the AFFECTED ARM (arm on the same side as the implant) for 4–8 weeks to prevent lead dislodgement. No reaching overhead, no heavy lifting. 2. WOUND CARE: Assess the implant site for signs of infection (redness, swelling, drainage, fever). 3. ECG MONITORING: Continuous telemetry for the first 24–48 hours to verify pacemaker function and detect complications. 4. DAILY PULSE CHECK: Teach the patient to count the pulse for 1 full minute daily. Report: rate below the SET RATE of the pacemaker, irregular beats, dizziness, or hiccups (hiccups may indicate lead displacement into the diaphragm). PATIENT TEACHING: - CARRY A PACEMAKER IDENTIFICATION CARD at all times (contains device model, set rate, manufacturer's info) — important in any medical emergency. - AVOID STRONG ELECTROMAGNETIC FIELDS: MRI is contraindicated unless the pacemaker is labeled 'MRI-conditional.' Avoid arc welding, high-voltage equipment. - HOUSEHOLD APPLIANCES ARE SAFE: Microwave ovens, cell phones, and most household appliances do NOT interfere with modern pacemakers. Cell phone should be kept 6 inches away from the device (hold on the opposite ear). - AIRPORT SECURITY: Inform security personnel — the device may trigger metal detectors. Use the pacemaker ID card.

Key Cardiac Pharmacology: Digoxin, Diuretics, ACE Inhibitors, Beta-Blockers, and Antidysrhythmics

Cardiac pharmacology is one of the HIGHEST-YIELD areas for the NLE. You must know each drug's indication, mechanism, nursing considerations (especially WHEN TO HOLD), adverse effects, and antidotes. --- 1. DIGOXIN (CARDIAC GLYCOSIDE) --- Mechanism: Positive INOTROPE (increases myocardial contractility by increasing intracellular calcium) + Negative CHRONOTROPE (slows heart rate by increasing vagal tone) Uses: Systolic HF (improves contractility); Atrial fibrillation (slows ventricular rate) CRITICAL NURSING CONSIDERATIONS: * BEFORE EVERY DOSE: Take APICAL PULSE for a FULL MINUTE. HOLD if apical rate < 60 bpm in adults (< 90–110 in infants). NOTIFY THE PHYSICIAN. * THERAPEUTIC SERUM LEVEL: 0.5–2 ng/mL. Above 2 ng/mL = TOXICITY. * DIGOXIN TOXICITY SIGNS: Anorexia, nausea, vomiting (earliest GI signs), VISUAL DISTURBANCES (yellow-green halos/halo vision, blurred vision — classic exam question), bradycardia, any new dysrhythmia. * HYPOKALEMIA POTENTIATES DIGOXIN TOXICITY: Low K+ makes cardiac cells more susceptible to digoxin's effects → life-threatening dysrhythmias. Monitor K+ especially in patients on loop or thiazide diuretics concurrently. * ANTIDOTE: DIGOXIN IMMUNE FAB (Digibind/DigiFab) — used for severe toxicity. * Do not give digoxin with calcium channel blockers or beta-blockers without close monitoring — both slow the heart rate additionally. --- 2. DIURETICS --- A. LOOP DIURETICS (Furosemide / Lasix) - Most POTENT diuretics — act on the Loop of Henle - Inhibit Na+/K+/2Cl- co-transporter → massive natriuresis and diuresis - Uses: Acute and chronic HF, pulmonary edema, hypertension - ADVERSE EFFECT: HYPOKALEMIA (electrolyte loss) → potentiates digoxin toxicity - OTOTOXICITY with rapid IV administration — give slowly - Monitor: electrolytes (K+, Na+, Mg2+), urine output, BP, and signs of dehydration B. THIAZIDE DIURETICS (Hydrochlorothiazide / HCTZ) - Moderate diuretics — act on distal convoluted tubule - Uses: Mild-moderate HF, hypertension (first-line in PhilPEN guidelines) - ADVERSE EFFECT: HYPOKALEMIA, hyperglycemia, hyperuricemia (gout) C. POTASSIUM-SPARING DIURETICS (Spironolactone) - Aldosterone antagonist → blocks sodium reabsorption without potassium loss - Uses: HF (proven to improve survival and reduce hospitalization — part of HF guideline therapy), hyperaldosteronism - ADVERSE EFFECT: HYPERKALEMIA — avoid potassium supplements, salt substitutes (KCl), NSAIDs - Gynecomastia in males (from anti-androgenic effect) - Contraindicated in renal insufficiency (accumulates potassium) --- 3. ACE INHIBITORS (Enalapril, Lisinopril, Captopril) --- Mechanism: Block conversion of Angiotensin I to Angiotensin II → reduce vasoconstriction (reduce afterload) + reduce aldosterone → reduce fluid retention Uses: HF (first-line; proven to improve survival), hypertension, post-MI, diabetic nephropathy ADVERSE EFFECTS: - DRY PERSISTENT COUGH (most common — bradykinin accumulation) — classic exam trap - HYPERKALEMIA (blocking aldosterone → potassium retention) - HYPOTENSION (first-dose effect) - ANGIOEDEMA (rare but life-threatening — sudden swelling of face, lips, tongue, throat) → STOP the drug, emergency airway management - Teratogenic — CONTRAINDICATED in pregnancy --- 4. ARBs (Losartan, Valsartan, Candesartan) --- - Angiotensin II receptor blockers — similar to ACE inhibitors but do NOT cause dry cough - Used as alternative when patients cannot tolerate ACE inhibitor cough - Monitor: hyperkalemia, hypotension, renal function --- 5. BETA-BLOCKERS (Carvedilol, Metoprolol succinate, Bisoprolol) --- Mechanism: Block beta-1 (cardiac) and beta-2 (peripheral) receptors → reduce heart rate, contractility, and blood pressure Uses: HF (proven to reduce mortality when used long-term), hypertension, post-MI, AFib rate control, angina IMPORTANT NURSING CONSIDERATIONS: - HOLD if HR < 60 bpm or SBP < 90 mmHg - NEVER STOP ABRUPTLY — rebound tachycardia and possible MI - Contraindicated in: acute decompensated HF (may worsen), severe bronchospasm/asthma (beta-2 blockade) - Started at VERY LOW DOSES in HF and titrated up slowly - Mask signs of hypoglycemia in diabetics (except sweating) --- 6. NITRATES (Isosorbide dinitrate, Nitroglycerin) --- - VENODILATORS → reduce preload → reduce pulmonary congestion - Also dilate coronary arteries → used for angina - ADVERSE: HEADACHE (most common), orthostatic hypotension - HOLD if SBP < 90 mmHg - CONTRAINDICATED with phosphodiesterase-5 inhibitors (sildenafil/Viagra) — severe hypotension - Nitroglycerin tablets are unstable: store in dark glass bottle, replace every 6 months --- 7. AMIODARONE (Antidysrhythmic) --- - BROAD-SPECTRUM antidysrhythmic: used for AFib and ventricular dysrhythmias (VT, VF) - Works on sodium, potassium, and calcium channels - ADVERSE EFFECTS (long-term use): * PULMONARY TOXICITY (amiodarone-induced pneumonitis/fibrosis) — monitor for new cough, dyspnea, worsening respiratory status → CHEST X-RAY * THYROID DYSFUNCTION (hypothyroidism or hyperthyroidism) — contains iodine → monitor TSH * QT PROLONGATION → risk of Torsades de Pointes (a dangerous VT variant) * Corneal microdeposits (most patients — usually asymptomatic) * Photosensitivity and blue-gray skin discoloration * Hepatotoxicity — monitor LFTs --- 8. ANTICOAGULANTS (Warfarin, DOACs) --- - WARFARIN (Coumadin): Vitamin K antagonist; used in AFib, DVT/PE, mechanical heart valves * Monitor INR — target 2–3 for AFib * Antidote: Vitamin K (slow reversal), Fresh Frozen Plasma (rapid reversal) * Many drug interactions (antibiotics, NSAIDs, aspirin) * Teach bleeding precautions - DOACs (Rivaroxaban, Apixaban, Dabigatran): Newer; no routine INR monitoring needed; used in non-valvular AFib --- 9. POSITIVE INOTROPES (IV — Critical Care) --- - DOBUTAMINE: Beta-1 agonist → increases contractility; used in acute decompensated HF in ICU - MILRINONE: Phosphodiesterase inhibitor → increases contractility and vasodilation; used in ICU - Both are IV infusions requiring hemodynamic monitoring

This patient has classic LEFT HF: PND (waking at midnight unable to breathe), orthopnea (uses 3 pillows), crackles (bilateral), and elevated BNP (520 pg/mL — normal < 100 pg/mL). The ABSENCE of peripheral edema and JVD confirms this is primarily LEFT HF, not right HF. PRIORITY DIAGNOSIS uses Maslow's hierarchy — oxygenation (SpO2 90%) is the most life-threatening problem. PRIORITY INTERVENTION is positioning (High Fowler's) as an IMMEDIATE, independent nursing action that reduces venous return and relieves dyspnea without waiting for a physician's order.

PATIENT TEACHING: (1) Do NOT stop eating malunggay or other vitamin K-rich foods, but MAINTAIN CONSISTENT intake from week to week. The key is consistency, not total avoidance. (2) Report changes in diet to the physician so warfarin doses can be adjusted. (3) Notify the physician about the subtherapeutic INR — a dose adjustment may be needed. (4) Teach stroke warning signs (FAST: Face drooping, Arm weakness, Speech difficulty, Time to call for help). This question tests the integration of pharmacology, dietary counseling, and cultural food knowledge relevant to Filipino patients.

This is a HIGH-COMPLEXITY integration question combining: weight gain (5 kg in 4 days > threshold of 2.5 kg/week → fluid retention), digoxin toxicity assessment (nausea + yellow vision + HR 58 bpm = clinical toxicity), the digoxin-hypokalemia interaction (K+ 3.1 = hypokalemia → amplifies digoxin toxicity), and medication safety priorities. Note: a digoxin level of 1.8 ng/mL is technically within the normal range BUT hypokalemia makes even 'normal' levels toxic. The NLE may test this nuance. Always prioritize the PATIENT'S SYMPTOMS over the lab number alone.

VF is the classic 'lethal rhythm' question in the NLE. Remember: VF = no cardiac output = cardiac arrest = CPR + DEFIBRILLATION. The key NLE points are: (1) CPR FIRST while someone else gets the defibrillator, (2) DEFIBRILLATION is UNSYNCHRONIZED (do not waste time synchronizing for an arrest rhythm), (3) Do NOT call a doctor before starting CPR — begin resuscitation immediately under your professional nursing duty (RA 9173 mandates nurses to act in emergencies). Distinguish from asystole (flatline, not shockable) and pulseless VT (wide complex, shockable — same treatment as VF).

Discharge teaching for pacemaker patients covers four major domains: self-monitoring (daily pulse), activity restrictions (arm movement), safety precautions (electromagnetic), and identification (ID card). The NLE will test whether you include ALL key points, particularly the daily pulse threshold (set rate) and the correct restriction (affected arm only, not both arms). Including hiccups as a reportable symptom (lead displacement to diaphragm) is a high-yield teaching point that differentiates excellent from average answers.