What is the immediate management for acute heart failure?

Immediate Management of Acute Heart Failure

The immediate management of acute heart failure requires rapid assessment of cardiopulmonary stability and prompt initiation of oxygen therapy, non-invasive ventilation for respiratory distress, and tailored pharmacological therapy based on blood pressure, with aggressive blood pressure reduction for hypertensive emergencies and inotropic support for hypotensive states. 1

Initial Assessment and Stabilization

• Determine cardiopulmonary stability by assessing respiratory distress (respiratory rate >25/min, SpO₂ <90%, increased work of breathing) and hemodynamic status (blood pressure, heart rhythm) 1, 2
• Establish continuous monitoring including pulse oximetry, blood pressure, respiratory rate, and ECG within minutes of patient contact 1
• Position patient upright to reduce work of breathing and improve ventilation 1, 2
• Assess mental status using the AVPU (alert, visual, pain, unresponsive) mnemonic as an indicator of hypoperfusion 1, 2
• Triage patients with persistent, significant dyspnoea or haemodynamic instability to a high-dependency setting (ICU/CCU) 1

Immediate Diagnostic Workup

• Obtain ECG to exclude ST elevation myocardial infarction and assess for arrhythmias 1, 3
• Measure plasma natriuretic peptide levels (BNP, NT-proBNP) to confirm diagnosis 1, 3
• Order laboratory tests including troponin, BUN/creatinine, electrolytes, complete blood count, and glucose 1, 2
• Perform chest X-ray to rule out alternative causes of dyspnea 1
• Consider bedside thoracic ultrasound for signs of interstitial edema if expertise is available 1, 2

Respiratory Support

• Administer oxygen therapy when SpO₂ <90% with a target of maintaining SpO₂ >90% 1, 2
• Initiate non-invasive positive pressure ventilation (CPAP, BiPAP) as soon as possible in patients with respiratory distress to decrease work of breathing and reduce the rate of mechanical endotracheal intubation 1
• Choose CPAP in the prehospital setting as it is simpler than PS-PEEP 1, 3
• Consider PS-PEEP in cases of acidosis and hypercapnia, particularly in patients with previous history of COPD 1, 2
• Monitor blood pressure closely during non-invasive ventilation as it can reduce blood pressure and should be used with caution in hypotensive patients 1, 2

Pharmacological Management Based on Blood Pressure

Hypertensive AHF (SBP >140 mmHg)

• Initiate aggressive blood pressure reduction (25% during first few hours) with IV vasodilators in combination with loop diuretics 1
• Administer IV nitroglycerin as the preferred vasodilator for pulmonary congestion through venodilation 4, 5
• Start with low doses and titrate up while monitoring blood pressure 3, 5
• Be aware of potential tachyphylaxis with nitroglycerin, necessitating incremental dosing 5, 6

Normotensive AHF (SBP 90-140 mmHg)

• Administer IV loop diuretics as first-line therapy 1, 3
• For new-onset HF or patients not on oral diuretics, give furosemide 40 mg IV 1, 3
• For established HF or patients on chronic oral diuretic therapy, administer at least equivalent to oral dose 1, 7
• Consider adding vasodilators if no response to initial diuretic therapy and if blood pressure allows 3, 7

Hypotensive AHF/Cardiogenic Shock (SBP <90 mmHg)

• Obtain immediate specialty consultation 1, 7
• Consider an initial fluid bolus of 250-500 mL if no overt fluid overload 7, 6
• Initiate dobutamine as the inotrope of choice for cardiac decompensation due to depressed contractility 8, 7
• Add norepinephrine if additional blood pressure support is needed 7, 6
• Consider mechanical circulatory support devices as a bridge to further therapeutic intervention in selected cases 7, 9

Management of Specific Precipitants

• Acute coronary syndrome: Implement immediate invasive strategy with intent to perform revascularization 1
• Rapid arrhythmias: Correct urgently with medical therapy, electrical cardioversion, or temporary pacing 1
• Acute mechanical cause: Perform echocardiography for diagnosis and consider circulatory support with surgical or percutaneous intervention 1
• Acute pulmonary embolism: When confirmed as cause of shock or hypotension, provide immediate specific treatment with primary reperfusion 1

Monitoring Response to Treatment

• Continuously monitor vital signs including blood pressure, heart rate, respiratory rate, and oxygen saturation 2, 3
• Assess urine output to evaluate response to diuretic therapy 1, 3
• Monitor for side effects of treatment, particularly hypotension with vasodilators and non-invasive ventilation 1, 2
• Reassess clinical status regularly to determine response to initial therapy 1

Common Pitfalls and Caveats

• Avoid excessive oxygen therapy in patients with COPD, targeting SpO₂ >90% rather than 95% 1, 2
• Be cautious with non-invasive ventilation in patients with cardiogenic shock and right ventricular failure 1, 2
• Recognize that troponin may be elevated in acute heart failure without acute coronary syndrome 1
• Be aware that tachyphylaxis may develop with nitroglycerin, requiring dose adjustments 5, 6
• Monitor for cyanide toxicity with prolonged nitroprusside use, especially in patients with renal insufficiency 6, 9