Acute heart failure can become respiratory failure within minutes. The failing heart cannot provide adequate forward flow or accommodate venous return. Pressure backs into the lungs or systemic circulation, causing pulmonary oedema, hypoxaemia, poor perfusion and shock. EMTs must distinguish “wet” congestion from “cold” hypoperfusion, treat the precipitating cause, support oxygenation, use diuretics/vasodilators only when appropriate and escalate early. Apply current Uganda cardiovascular protocols and senior clinical supervision.
1. Learning objectives
- Define acute, chronic, left-sided, right-sided and biventricular heart failure.
- Recognise pulmonary oedema, systemic congestion, low-output shock and life-threatening deterioration.
- Perform focused history, examination, ABCDE, ECG and targeted investigations.
- Explain oxygen, non-invasive ventilation, loop diuretics, nitrates, inotropes and precipitant treatment.
- Provide nursing care, fluid balance, monitoring, referral and discharge prevention.
2. What is heart failure?
Heart failure is a clinical syndrome in which structural or functional cardiac disease causes inadequate cardiac output and/or elevated filling pressures. Acute decompensation may follow myocardial infarction, uncontrolled hypertension, arrhythmia, infection, valve disease, renal failure, anaemia, pregnancy-related cardiomyopathy or missed medicines.
| Pattern | Main problem | Common findings |
|---|---|---|
| Left-sided failure | High pulmonary venous pressure and poor systemic output. | Dyspnoea, orthopnoea, crackles, pulmonary oedema, fatigue. |
| Right-sided failure | Systemic venous congestion. | Raised JVP, peripheral oedema, hepatomegaly, ascites. |
| Acute pulmonary oedema | Rapid fluid movement into alveoli. | Severe breathlessness, pink froth, crackles, hypoxaemia. |
| Cardiogenic shock | Critically low cardiac output and tissue perfusion. | Hypotension, cold mottled skin, confusion, oliguria, lactate rise. |
3. Causes and precipitants
- Acute coronary syndrome, myocarditis, cardiomyopathy, valve disease and congenital heart disease.
- Hypertensive emergency, tachyarrhythmia/bradyarrhythmia, infection/sepsis and pulmonary embolism.
- Renal failure, anaemia, thyroid disease, pregnancy/peripartum cardiomyopathy and excess salt/fluid.
- Missed diuretics/heart medicines, NSAIDs, excess alcohol, stimulant drugs and high-output states.
4. Clinical features and severity
| Domain | Findings | Danger signs |
|---|---|---|
| Breathing | Dyspnoea, orthopnoea, PND, tachypnoea, crackles, wheeze. | Severe distress, pink froth, cyanosis, exhaustion or inability to speak. |
| Congestion | Raised JVP, oedema, weight gain, ascites, hepatomegaly. | Rapid swelling, tense abdomen, severe liver/kidney dysfunction. |
| Perfusion | Fatigue, cool hands, weak pulse, narrow pulse pressure. | Hypotension, confusion, mottling, anuria or shock. |
| Rhythm/ischaemia | Palpitations, chest pain, irregular pulse. | Syncope, ventricular dysrhythmia, STEMI or heart block. |
5. Focused history and examination
- Onset and speed of dyspnoea; orthopnoea, nocturnal breathlessness, chest pain, cough, sputum and weight change.
- Known heart/renal/lung disease, previous admissions, ejection fraction, valve disease and pregnancy status.
- Medication adherence, diuretic dose, NSAIDs, salt/fluid intake and recent infection.
- Examine position, speech, respiratory effort, crackles/wheeze, JVP, oedema, perfusion, BP and rhythm.
- Search for ACS, hypertensive crisis, sepsis, arrhythmia, pulmonary embolism and myocarditis.
6. ABCDE assessment
| Step | Assess | Action |
|---|---|---|
| A – Airway | Secretions, pink froth, consciousness and aspiration risk. | Suction, upright position, airway readiness and early expert help. |
| B – Breathing | RR, SpO₂, crackles, wheeze, work and fatigue. | Oxygen for hypoxaemia, CPAP/NIV for suitable severe oedema and ventilatory escalation. |
| C – Circulation | BP, pulse, rhythm, perfusion, JVP, oedema and urine. | ECG monitor, IV access, cautious fluid strategy, diuretic/vasodilator decision and shock escalation. |
| D – Disability | AVPU/GCS, glucose, agitation and confusion. | Check glucose, recognise hypoxia/low output and protect airway. |
| E – Exposure | Oedema, skin, infection, calf signs, pregnancy and medication patches. | Keep warm, find precipitant and preserve dignity. |
7. Immediate treatment
- Sit upright with legs dependent if blood pressure allows; avoid lying flat in pulmonary oedema.
- Give oxygen for hypoxaemia or severe distress, titrating to the clinical target; monitor continuously.
- Consider CPAP/NIV for severe pulmonary oedema with suitable blood pressure, alertness and airway protection.
- Use IV loop diuretic when congestion is present, guided by prior therapy, renal function, BP and senior prescription.
- Use nitrates/vasodilators in hypertensive pulmonary oedema when BP is adequate; avoid in hypotension or right-ventricular preload dependence.
- Do not give routine fluid boluses to a wet patient; if cardiogenic shock or right-ventricular infarction is suspected, seek expert haemodynamic guidance.
8. Investigations
- Continuous ECG, BP, SpO₂, respiratory rate, temperature, urine output and mental-state monitoring.
- 12-lead ECG for ACS, arrhythmia, ischaemia, hypertrophy or heart block.
- Chest X-ray/ultrasound for oedema, effusion, pneumonia and pneumothorax.
- FBC, electrolytes, urea/creatinine, glucose, liver tests, troponin, BNP/NT-proBNP and blood gas when indicated.
- Bedside echo where available to assess ventricular function, valves, pericardium and fluid status.
- Investigate PE, infection, thyroid disease, anaemia and pregnancy-related causes according to presentation.
9. Treat the precipitating emergency
| Precipitant | Clues | Direction |
|---|---|---|
| ACS | Chest pain, dynamic ECG/troponin changes. | ACS pathway, antiplatelet/reperfusion and cardiology referral. |
| Hypertensive crisis | Very high BP with oedema, neurological/renal injury. | Controlled IV reduction by senior clinician; avoid sudden overcorrection. |
| Arrhythmia | Fast/slow irregular rhythm, syncope or palpitations. | ECG-directed rate/rhythm management, cardioversion if unstable. |
| Infection/sepsis | Fever, cough, urinary or wound source, shock. | Sepsis treatment balanced with fluid intolerance and congestion. |
| PE/tamponade | Sudden dyspnoea, RV strain, JVP, hypotension or muffled sounds. | Urgent imaging/specialist management; do not assume all breathlessness is oedema. |
10. Pharmacological and advanced care
- Loop diuretic: relieves fluid congestion; monitor urine, renal function, potassium, BP and response.
- Vasodilator: reduces preload/afterload in hypertensive congestion; requires BP monitoring.
- Vasopressor/inotrope: reserved for cardiogenic shock/low output under critical-care supervision.
- Anticoagulation/antiplatelet: used for the identified indication such as ACS, AF or PE, after bleeding assessment.
- Mechanical support: NIV, ventilation, intra-aortic/advanced support or transfer may be needed for refractory failure.
- Avoid NSAIDs, unprescribed fluid, unnecessary sedatives and abrupt withdrawal of essential medicines without senior advice.
11. Nursing and EMT care plan
| Problem | Interventions | Evaluate |
|---|---|---|
| Pulmonary congestion | Upright position, oxygen/NIV, suction, respiratory observations and fluid restriction if prescribed. | SpO₂, RR, crackles, effort, speech and oxygen requirement. |
| Fluid excess | Strict intake/output, daily weight, diuretic administration and renal/electrolyte checks. | Urine, oedema, weight, creatinine, potassium and breathlessness. |
| Low cardiac output | Monitor BP, rhythm, perfusion, mentation, temperature and lactate. | Pulse quality, refill, urine and consciousness. |
| Medication risk | Check BP, renal function, potassium, drug interactions and response. | No hypotension, arrhythmia or renal toxicity. |
| Anxiety/fatigue | Explain NIV, conserve energy, support family and provide rest. | Cooperation, reduced distress and safe mobilisation. |
12. Special populations
- Right-ventricular failure: excessive diuresis or nitrates can reduce preload and worsen shock; seek specialist guidance.
- Renal failure: fluid and diuretic decisions need close monitoring and possible dialysis.
- Pregnancy/peripartum cardiomyopathy: involve obstetric/cardiology teams urgently.
- Older/frail patients: assess delirium, falls, polypharmacy and goals of care.
- Children: assess congenital/rheumatic disease and use weight-based therapy in a paediatric setting.
13. Discharge and prevention
- Confirm euvolaemia, stable renal function/electrolytes, safe oxygenation, medication access and follow-up.
- Teach daily weight/symptom monitoring, low-salt plan, prescribed fluid limit, medicine adherence and early warning signs.
- Stop smoking, control BP/diabetes, treat sleep apnoea and attend cardiac rehabilitation.
- Return urgently for breathlessness at rest, new orthopnoea, chest pain, fainting, confusion, rapid weight gain or reduced urine.
14. Clinical scenarios
Scenario 1 – hypertensive pulmonary oedema. A patient is sitting upright, gasping, BP 220/120, SpO₂ 78% and coughing pink froth. Give oxygen, urgent NIV/CPAP assessment, consider nitrates under protocol, monitor continuously and escalate for critical care.
Scenario 2 – cold cardiogenic shock. A patient with known heart failure is cold, confused, hypotensive and passing little urine. Do not give repeated fluid boluses; obtain ECG/IV access, treat reversible cause and urgently involve critical care for vasoactive support.
Scenario 3 – missed diuretics. A patient has progressive leg swelling, weight gain and orthopnoea after missing medicines. Assess for ACS/infection, monitor renal function and follow the prescribed diuretic plan with education.
Scenario 4 – acute precipitant. A patient with oedema develops fever and productive cough. Treat possible pneumonia/sepsis while carefully balancing antibiotics, fluids, oxygen and congestion.
15. Common errors to avoid
- Lying a breathless pulmonary-oedema patient flat.
- Giving large unmonitored fluid boluses to a congested patient.
- Using nitrates or diuretics in hypotension without senior guidance.
- Missing ACS, arrhythmia, PE, infection or tamponade as the precipitant.
- Failing to chart fluid balance, urine, weight, renal function and electrolytes.
- Discharging without medication reconciliation, follow-up and return precautions.
Heart-failure emergency check – “WET-COLD”
W – Work of breathing and pulmonary oedema
E – ECG and precipitant search
T – Treat congestion carefully
C – Circulation and perfusion
O – Oxygen/NIV when indicated
L – Log fluid, urine and laboratory trends
D – Diuretics/vasodilators only when appropriate
W – Work of breathing and pulmonary oedema
E – ECG and precipitant search
T – Treat congestion carefully
C – Circulation and perfusion
O – Oxygen/NIV when indicated
L – Log fluid, urine and laboratory trends
D – Diuretics/vasodilators only when appropriate
16. Revision questions
- Differentiate left-sided, right-sided and biventricular failure.
- List six causes of acute decompensation.
- Describe ABCDE management of acute pulmonary oedema.
- When are diuretics, nitrates, NIV and vasopressors considered?
- Why can fluid boluses harm a congested patient?
- List six discharge and prevention measures.
17. Key take-home points
- Acute heart failure may present as pulmonary oedema, systemic congestion, low output or shock.
- Position upright, support oxygenation and monitor ECG, BP, urine and mental state.
- Diuretics relieve congestion; nitrates help selected hypertensive patients; shock needs expert vasoactive support.
- Always search for ACS, arrhythmia, infection, PE, valve disease and renal causes.
- Fluid balance, renal/electrolyte review, education and follow-up are essential.
Safety note: This is educational content for EMT students. Oxygen targets, diuretic dose, nitrates, NIV, vasoactive medicines and fluid decisions must follow current Uganda protocols and senior cardiovascular/critical-care supervision.
References for further study
- American Heart Association: Heart-failure medicines
- European Society of Cardiology: Heart-failure care resources
- WHO emergency-service protocol: acute pulmonary oedema
- Uganda Ministry of Health: current cardiovascular, oxygen-therapy and emergency-care guidelines.