What medications are used to treat heart failure with pulmonary congestion?

Medications for Heart Failure with Pulmonary Congestion

Immediate First-Line Treatment

Patients with heart failure and pulmonary congestion should be promptly treated with intravenous loop diuretics as the cornerstone of therapy, combined with vasodilators (nitrates) when systolic blood pressure is adequate (>90-110 mmHg). 1, 2

Loop Diuretics (Essential First-Line)

• Intravenous loop diuretics must be administered within 60 minutes of presentation to improve symptoms and reduce morbidity 1, 2
• Initial dosing strategy: 1, 2, 3
  • If diuretic-naïve: Start with 20-40 mg IV furosemide
  • If already on oral diuretics: Use at least double the current oral daily dose IV
  • Maximum doses can reach 400-600 mg furosemide per day, or up to 1000 mg in severe renal dysfunction
• Target response within 2-6 hours: 2, 3
  • Urinary sodium ≥50-70 mmol/L within 2 hours
  • Urine output ≥100-150 mL/hour within 6 hours
• If inadequate response: Double the dose or add a second diuretic (thiazide or acetazolamide) 1

Vasodilators (Nitrates) - Critical for Adequate Blood Pressure

Nitrates are superior to high-dose diuretics alone for severe pulmonary edema and should be initiated immediately when SBP >90-110 mmHg. 2

• Immediate administration options: 2
  • Nitroglycerin spray: 400 mcg (2 puffs) every 5-10 minutes
  • Sublingual nitroglycerin: 0.25-0.5 mg
  • IV nitroglycerin: Start 10-20 mcg/min, increase by 5-10 mcg/min every 3-5 minutes as needed
• Monitor blood pressure every 5-15 minutes during titration 2

Oxygen Supplementation

• **Administer supplemental oxygen immediately if SpO₂ <90%** to maintain arterial saturation >90% 2, 4
• High-flow oxygen when PaO₂ <60 mmHg 2
• Target SpO₂ >90% but avoid hyperoxia (can cause vasoconstriction) 4

Combination Diuretic Therapy for Refractory Congestion

When initial loop diuretic therapy is inadequate, early combination therapy with acetazolamide or thiazides is reasonable. 1, 3

Acetazolamide (Emerging Evidence)

• Dose: 500 mg IV once daily, particularly useful if baseline bicarbonate ≥27 mmol/L 4, 3
• Use only in the first 3 days to prevent severe metabolic disturbances 4, 3
• Remains effective even with worsening renal dysfunction 4

Thiazide Combination

• Add hydrochlorothiazide or metolazone to loop diuretics for resistant edema 1, 4
• Use with caution to avoid dehydration, hypovolemia, hyponatremia, or hypokalemia 1

Adjunctive Symptomatic Treatment

Morphine

• Administer 3 mg IV bolus immediately upon establishing IV access for severe dyspnea and anxiety 2
• Repeat dosing as needed 2, 4
• Induces venodilation, mild arterial dilation, and reduces heart rate 2

Non-Invasive Ventilation

• Consider CPAP or BiPAP when respiratory rate >20-25 breaths/min or SpO₂ <90% 2, 4
• Improves breathlessness and reduces hypercapnia and acidosis 2
• Avoid if SBP <85 mmHg 2

Guideline-Directed Medical Therapy (GDMT) - Must Initiate During Hospitalization

Do not wait until after discharge to initiate or optimize GDMT—this must begin during hospitalization for heart failure with reduced ejection fraction (HFrEF). 1

Core GDMT Components

• ACE inhibitors/ARBs/ARNIs: Start short-acting ACE inhibitor (captopril 1-6.25 mg) after initial stabilization 1, 2
• Beta-blockers: Initiate at low doses before discharge for secondary prevention 1, 2
• Aldosterone antagonists (spironolactone/eplerenone): For post-MI patients with LVEF ≤40% and symptomatic HF 1, 2
• SGLT2 inhibitors: Initiation before or shortly after discharge reduces cardiovascular mortality and hospitalization 1

Critical Implementation Point

• Only 1% of patients receive target doses of all three core medications (ACE-I/ARB/ARNI, beta-blocker, MRA) within 12 months of hospitalization 1
• Do not discontinue oral GDMT during hospitalization—continuation is associated with lower post-discharge death and readmission 1

Treatment Algorithm Based on Blood Pressure

If SBP >110 mmHg:

• Full-dose IV loop diuretics + IV nitrates 2, 4
• Consider non-invasive ventilation if respiratory difficulty 4

If SBP 90-110 mmHg:

• IV loop diuretics (standard dose) + cautious nitrate use with close monitoring 2

If SBP <90 mmHg:

• Lower initial diuretic dose, avoid vasodilators 4
• Do NOT use inotropes unless symptomatic hypotension or hypoperfusion present 2, 4

Essential Monitoring Requirements

Therapy must be titrated with the goal to completely resolve clinical evidence of congestion before discharge. 1

• Monitor urine output hourly (target >100-150 mL/h in first 6 hours) 2
• Check electrolytes and renal function daily during active medication adjustment 1
• Small increases in creatinine (0.3 mg/dL) should not prompt premature discontinuation of diuresis 1
• Monitor blood pressure every 5-15 minutes during vasodilator titration 2

Critical Pitfalls to Avoid

• Persistent congestion at discharge occurs in 25-50% of patients and is associated with higher mortality and readmission 1
• Do not assume GDMT will be initiated or optimized after discharge—42% of patients receive no GDMT within 30 days post-hospitalization 1
• Avoid potassium-sparing diuretics (except aldosterone antagonists) when combining with ACE-I/ARB due to hyperkalemia risk 1
• Do not use thiazides if GFR <30 mL/min except synergistically with loop diuretics 1

Discharge Planning

• Include a specific plan for diuretic adjustment to decrease rehospitalizations 1
• Educate patients on self-adjustment of diuretic dose based on daily weight measurements 1
• Ensure early follow-up visit within 2 weeks to up-titrate GDMT to target doses 3