What is the initial management for a congestive heart failure (CHF) exacerbation?

Initial Management of CHF Exacerbation

For patients presenting with acute CHF exacerbation, immediately administer intravenous loop diuretics at a dose equal to or exceeding their chronic oral daily dose, while continuing ACE inhibitors/ARBs and beta-blockers unless hemodynamically unstable. 1, 2

Immediate Assessment (First 15 Minutes)

• Obtain ECG and cardiac troponin to identify acute coronary syndrome as a precipitating cause 1, 3
• Assess hemodynamic status: Check blood pressure, heart rate, jugular venous pressure, peripheral perfusion (cool extremities, altered mental status), and signs of congestion (rales, edema, ascites) 1, 3
• Measure oxygen saturation and administer supplemental oxygen if SpO2 <90% 3
• Check BNP or NT-proBNP if the diagnosis is uncertain, though interpret in context of clinical findings 1, 3

Intravenous Diuretic Therapy (Primary Treatment)

Initial Dosing Algorithm

For patients already on chronic loop diuretics:

• Start with IV furosemide dose ≥ their total daily oral dose (e.g., if taking 40 mg PO twice daily = 80 mg total, give at least 80 mg IV initially) 1, 2
• Administer as single bolus or divided doses (e.g., 40 mg IV every 2 hours) 2

For diuretic-naïve patients:

• Start with furosemide 20-40 mg IV 2, 3

Monitoring Diuretic Response (First 2-6 Hours)

• Target urine output: 100-150 mL/hour in first 6 hours or 3-5 L in 24 hours 4
• Target weight loss: 0.5-1.0 kg daily 2, 4
• Check spot urine sodium at 2 hours: adequate response is >50-70 mmol/L 4
• Monitor vital signs, fluid intake/output, and daily weights (same time each day) 1

Dose Escalation for Inadequate Response

If diuresis remains inadequate after initial dose:

1. Increase loop diuretic dose by doubling or giving higher boluses 1
2. Add a second diuretic (metolazone 2.5-10 mg PO daily, spironolactone 25-50 mg daily, or IV chlorothiazide) 1, 4
3. Consider continuous IV furosemide infusion (5-20 mg/hour) if bolus dosing fails 1

Critical Medication Management

Continue Guideline-Directed Medical Therapy

DO NOT STOP these medications unless hemodynamically unstable (SBP <90 mmHg with hypoperfusion):

• Continue ACE inhibitors or ARBs during hospitalization—they work synergistically with diuretics 1, 2, 3
• Continue beta-blockers in most patients—withholding worsens outcomes 1, 3
• Exception: Consider temporary reduction if marked volume overload or recent uptitration 1

When to Initiate Beta-Blockers (If Not Already On)

• Start at low dose only after volume optimization and discontinuation of IV inotropes 1, 3
• Do not initiate during active decompensation with IV vasopressors 1

Adjunctive Vasodilator Therapy

For patients with SBP >110 mmHg and severe congestion:

• Consider IV nitroglycerin (starting 10-20 mcg/min, titrate up) as adjunct to diuretics 1, 3
• Alternative: IV nitroprusside or nesiritide (though nesiritide requires conservative dosing without bolus due to hypotension risk) 1
• Sublingual nitroglycerin may be used initially while establishing IV access 3

Management of Hypotension (SBP <90 mmHg)

If hypotension with signs of hypoperfusion (cool extremities, altered mental status, oliguria, elevated lactate):

• HOLD diuretics temporarily until perfusion restored 2
• Administer IV inotropes: dobutamine (2.5-10 mcg/kg/min), dopamine (2-20 mcg/kg/min), or milrinone 1, 3, 5
• Resume diuretics once SBP ≥90 mmHg and perfusion improves 2
• Note: Inotropes should NOT be used in normotensive patients without hypoperfusion 1

Daily Monitoring Requirements

• Daily weights at same time each day 1, 2
• Daily electrolytes (especially potassium), BUN, and creatinine during active IV diuresis 1, 2
• Fluid intake and output with running totals 1
• Supine and standing blood pressure to detect orthostatic hypotension 1

Rescue Therapy for Refractory Congestion

If congestion persists despite maximized diuretic therapy (48-72 hours):

• Consider ultrafiltration for patients with obvious volume overload not responding to escalated diuretics 1, 3
• Invasive hemodynamic monitoring (Swan-Ganz catheter) may guide therapy in patients with respiratory distress or unclear volume status 1

Essential Supportive Care

• Thromboembolism prophylaxis for all hospitalized HF patients (subcutaneous heparin or enoxaparin) 1, 3
• Medication reconciliation on admission and discharge 1

Common Pitfalls to Avoid

• Starting IV diuretic dose lower than home oral dose leads to inadequate decongestion and prolonged hospitalization 2
• Stopping ACE inhibitors/ARBs or beta-blockers unnecessarily worsens outcomes—only hold if true hemodynamic instability 1, 2
• Excessive concern about mild azotemia or hypotension can lead to underdiuresis and refractory edema—continue diuresis unless severe complications 2
• Discharging before adequate decongestion increases readmission rates—ensure weight loss and symptom resolution before discharge 1, 4
• Using inotropes in normotensive patients without hypoperfusion increases mortality 1, 5