What is the treatment for pulmonary edema?

Treatment of Pulmonary Edema

For acute cardiogenic pulmonary edema, immediately apply CPAP (5-15 cmH₂O) or non-invasive positive pressure ventilation as first-line respiratory support, combined with intravenous nitroglycerin and loop diuretics, while positioning the patient upright and providing supplemental oxygen to maintain SpO₂ 94-98%. 1, 2

Immediate Stabilization

Respiratory Support

• Apply CPAP (5-15 cmH₂O) or bilevel NIV immediately as the primary intervention before considering intubation - both modalities reduce mortality (RR 0.80) and need for intubation (RR 0.60) by improving oxygenation, decreasing left ventricular afterload, and reducing respiratory muscle work 2
• Start CPAP at 5-10 cmH₂O and titrate up to 15 cmH₂O based on clinical response, ensuring adequate FiO₂ to maintain target saturations 1
• In the prehospital setting, CPAP decreases the need for intubation (RR 0.31,95% CI 0.17-0.55) when applied early in patients with respiratory rate >25 breaths/min and SpO₂ <90% 1, 2

Positioning and Oxygenation

• Position patient upright (semi-seated) to decrease venous return and improve ventilation 1, 2
• Administer supplemental oxygen to maintain SpO₂ 94-98% (or 88-92% if at risk for hypercapnia) 1, 2
• Avoid routine oxygen in non-hypoxemic patients as it causes vasoconstriction and reduces cardiac output 2

Monitoring

• Establish continuous monitoring of ECG, blood pressure, heart rate, respiratory rate, and oxygen saturation 1, 2
• Obtain intravenous access immediately for medication administration 2

Pharmacological Management

First-Line Vasodilators

• Administer nitroglycerin as first-line therapy: start with sublingual 0.4-0.6 mg, repeated every 5-10 minutes up to four times 2
• Transition to intravenous nitroglycerin at 0.3-0.5 μg/kg/min if systolic blood pressure is adequate, titrating to the highest hemodynamically tolerable dose while maintaining SBP >85-90 mmHg 2
• For hypertensive pulmonary edema, aim for initial rapid reduction of systolic or diastolic BP by 30 mmHg (approximately 25% during first few hours), using IV vasodilators to decrease venous preload and arterial afterload 1, 2
• Consider sodium nitroprusside (starting at 0.1 μg/kg/min) for patients not responsive to nitrate therapy 2

Critical Pitfall: Monitor for nitrate tolerance, which develops rapidly with high-dose IV administration 2

Diuretics

• Administer intravenous loop diuretics (furosemide 20-80 mg IV) shortly after diagnosis for rapid symptomatic relief through immediate venodilation and subsequent fluid removal 2, 3
• Keep furosemide doses judicious to avoid worsening renal function and increased long-term mortality 2
• For resistant peripheral edema, consider combining loop and thiazide diuretics 2
• In severe renal dysfunction with refractory fluid retention, continuous veno-venous hemofiltration (CVVH) may be necessary 2

Morphine

• Administer morphine 3-5 mg IV in the early stage for patients with severe acute heart failure, particularly when associated with restlessness and dyspnea - reduces anxiety, decreases preload, and improves dyspnea 1, 2

CPAP Application Criteria and Contraindications

When to Apply CPAP

• Respiratory rate >25 breaths/min despite conventional oxygen therapy 1
• SpO₂ <90% despite conventional oxygen therapy 1
• Clinical signs of respiratory distress with cardiogenic pulmonary edema 1

Absolute Contraindications to CPAP

• Hypotension (systolic blood pressure <90 mmHg) 1
• Active vomiting or inability to protect airway 1
• Depressed consciousness 1
• Suspected pneumothorax 1
• Cardiogenic shock or acute coronary syndrome with ongoing ischemia 4

When to Proceed to Intubation Despite CPAP

• Persistent hypoxemia despite CPAP therapy 1, 2
• Hypercapnia with acidosis (low pH) 1
• Deteriorating mental status or inability to protect airway 1, 2
• Hemodynamic instability despite appropriate interventions 1, 2

Management Based on Underlying Cause

Acute Coronary Syndrome

• Perform urgent myocardial reperfusion therapy via cardiac catheterization or thrombolytic therapy for ST-elevation or new left bundle branch block 2
• Identify signs of acute coronary syndrome through focused history, physical examination, and ECG 2

Hypertensive Emergency

• Use intravenous vasodilators (nitroglycerin or nitroprusside) combined with loop diuretics 1
• Aim for rapid initial BP reduction of approximately 25% during first few hours 1

Valvular Disease or Arrhythmias

• Identify and treat underlying valvular disease or arrhythmias as the precipitating cause 1

Advanced Interventions for Refractory Cases

Hemodynamic Monitoring

• Consider pulmonary artery catheter monitoring if clinical course is deteriorating, diagnostic uncertainty exists, or high-dose vasodilators/inotropes are required 2

Mechanical Support

• Consider intraaortic balloon counterpulsation (IABP) for severe refractory pulmonary edema, particularly if urgent cardiac catheterization is needed 2

Critical Pitfalls to Avoid

• Never use beta-blockers in patients with frank cardiac failure evidenced by pulmonary congestion 2
• Avoid aggressive simultaneous use of multiple hypotensive agents, which can initiate a cycle of hypoperfusion-ischemia 2
• Do not apply CPAP in non-cardiogenic pulmonary edema (ARDS) in prehospital settings - these patients require immediate transport for potential intubation 4
• Monitor electrolytes closely as diuretic therapy can cause imbalance 2

Special Consideration: Non-Cardiogenic vs. Cardiogenic

For non-cardiogenic acute pulmonary edema (ARDS from pneumonia, aspiration, etc.), CPAP/NIV should only be attempted in highly controlled ICU settings with immediate intubation capability, not in prehospital environments - delayed intubation in ARDS significantly increases mortality 4

Monitoring Treatment Response

• Assess clinical parameters including respiratory rate, use of accessory muscles, and dyspnea improvement 1
• Monitor oxygen saturation, arterial blood gases, renal function, and electrolytes 1
• Communicate unsatisfactory responses to treatment immediately 2
• For patients with previous COPD or signs of fatigue showing acidosis and hypercapnia, prefer pressure-support positive end-expiratory pressure (PS-PEEP) over CPAP 2