Management

Most outpatient GDMT of heart failure should be continued during ADHF unless any specific contraindication

Drug

Continue?

ACEi/ARB/ARNI

Hold if hypotension/AKI

Beta-blocker

Continue unless shock

MRA

Usually continue

SGLT2 inhibitor

Can continue/start once stable

1. Oxygen Therapy

  • Target SpO₂ > 92%
  • Avoid routine oxygen if saturation normal

 Non-Invasive Ventilation 

CPAP/BiPAP

Benefits:

  • Preload
  • Afterload
  • Improves oxygenation
  • Reduces intubation rate

Indicated in:

  • Acute pulmonary edema
  • Severe dyspnea

Intubation 

Indications:Altered sensorium,Severe hypoxia,Cardiogenic shock

 Use caution: Positive pressure can reduce preload in hypotensive patients.


—2. Decongestion 

 IV Loop Diuretics (First-Line)

Drug:-Furosemide/bumetanide IV(1 mg IV bumetanide = 40 mg IV furosemide)

Dosing Strategy: if chronic user: ≥ home oral dose IV equivalent.The DOSE-HF trial demonstrated that multiplying the oral diuretic dose by approximately 2.5 improves fluid and weight loss.

For loop diuretic naïve patients, this is often 40 to 80 mg of IV furosemide.

Urine Sodium–Guided Diuretic Strategy in Heart Failure

1. Rationale

  • Increasing evidence supports urine sodium–based monitoring for:
    • Assessing diuretic response
    • Early dose titration
  • More reliable than clinical markers alone (e.g., weight, edema)


2. Early Assessment of Diuretic Response

Timing

  • Urine sodium (UNa): 1–2 hours after IV loop diuretic
  • Urine output (UOP): within 2-  6 hours

Interpretation of Urine Sodium

  • < 50–70 mmol/L Poor response
  • ≥ 100 mmol/L Good / excellent response
  • U/0 <150ml/hr-Poor response


3. Natriuretic Response Prediction

  • Uses spot urine sample
  • More accurate than urine sodium alone
  • Helps predict loop diuretic effectiveness early


4. Diuretic Titration Strategy

Initial Goal

  • Identify effective diuretic dose that produces adequate natriuresis

Then

  • Repeat/adjust dose to achieve target decongestion rate


5. Targets of Decongestion

  • Net sodium loss: 230–500 mmol/day
  • Net fluid loss: 3–5 L/day

(Always individualize based on patient status)


Step 6: Escalation Strategy (if resistance persists)

  • Increase loop diuretic dose (stepwise doubling)
  • Add:
    • Thiazide (sequential nephron blockade)
    • SGLT2 inhibitor
  • Consider combination strategies early if poor natriuresis


Step 7: Safety

  • Avoid excessive dosing
  • >1000 mg furosemide equivalent/day caution
  • Monitor:
    • Electrolytes
    • Renal function


 Diuretic Resistance

 There is no fixed rule for when to add a thiazide to loop diuretics.

  • In practice, loop diuretic doses can be increased beyond usual “maximum” limits if needed.
  • In resistant cases, high doses may be used safely, such as:
    • IV bumetanide up to 12.5 mg
    • IV furosemide up to 500 mg

 These higher doses are sometimes necessary when patients do not respond to standard treatment.

To improve (augment) diuretic response, mineralocorticoid receptor antagonists (MRAs) may be used in higher doses (>100 mg/day).

Giving hypertonic saline (3% NaCl) with diuretics can sometimes increase urine output, but this needs close monitoring (electrolytes, fluid status).

Ultrafiltration (UF) is another option in acute decompensated heart failure (ADHF):

  • It removes excess fluid directly from blood
  • Done using venovenous access (like dialysis)


Diuretics in Decompensated Heart Failure (Dose Table)

1. Loop Diuretics (IV Bolus)

Drug

Initial Dose

Max Single Dose

Furosemide

40 mg

500 mg

Bumetanide

1 mg

12.5 mg

Torsemide


2. Loop Diuretics (IV Continuous Infusion)

Drug

Initial Rate

Max Rate

Key Considerations

Furosemide

5 mg/h

80 mg/h

Give bolus before infusion to avoid delayed onset

Bumetanide

0.25 mg/h

2 mg/h

Less ototoxicity; may cause severe myalgia at high doses


3. Thiazides (Add-on to Loop Diuretics)

Drug

Route

Initial Dose

Max Dose

Key Considerations

Chlorothiazide

IV

500 mg

1000 mg

Short duration needs 2–3 doses/day

Metolazone

Oral

5 mg

10 mg

Erratic absorption, delayed onset; potent

Hydrochlorothiazide (HCTZ)

Oral

50 mg

100 mg

Longer half-life once/twice daily


Vasodilators (If BP > 110 mmHg)

1. HFrEF vs HFpEF (Core Difference)

  • HFrEF:
    • Vasodilators preload + afterload
    • cardiac output + rapid symptom relief
    • More beneficial
  • HFpEF:
    • Systolic function already normal
    • afterload minimal CO increase
    • Higher risk of stroke volume + hypotension
    • Use cautiously


2. When to Use Vasodilators

Add to diuretics ONLY if BP adequate

Best indications:

  • Hypertensive urgency/emergency
  • Severe dyspnea / impending respiratory failure
  • High SVR on invasive monitoring

 Not for routine use (no mortality benefit, no improved diuresis)

3. General Principles

  • Rapid onset + short half-life easy titration
  • Goal: symptom relief (dyspnea), not outcome improvement
  • Different from chronic oral vasodilators (ACEi/ARB)


4. Types of Vasodilation

  • Venodilators (low-dose nitrates) preload filling pressures
  • Arterial vasodilators (high-dose nitrates, hydralazine) afterload
  • Balanced (nitroprusside) preload + afterload


5. Important Clinical Points

  • Nitrate tolerance develops within hours need 8–12 hr nitrate-free interval
  • Hydralazine + nitrates:
    • Combined preload + afterload reduction
    • Use if ACEi/ARB not possible (e.g., renal failure, hyperkalemia, pregnancy)
  • Nitroprusside:
    • Very potent use short-term
    • Risk: cyanide toxicity (high dose/prolonged use, renal/hepatic failure)


Vasodilators in ADHF (Drug Table)

IV Vasodilators

Drug

Initial Dose

Max Dose

Hemodynamic Effect

Enalaprilat

1.25 mg IV q6–8h

5 mg q6–8h

Venous + arterial

Nitroprusside

0.2 mcg/kg/min

10 mcg/kg/min (caution >5)

Balanced

Nitroglycerin

10 mcg/min

400 mcg/min

Venous (low dose), arterial (high dose)


Oral Vasodilators

Drug

Initial Dose

Max Dose

Effect

Hydralazine

25 mg q6–8h

100 mg q6–8h

Arterial

Isosorbide dinitrate

10 mg q6–8h

40 mg q6–8h

Venous

Captopril

6.25 mg q8h

50 mg q8h

Venous + arterial



Inotropes 

Multiple clinical trials have shown that positive inotropic drugs increase adverse events, including mortality, so their routine use in acute decompensated heart failure (ADHF) is not recommended. Their harmful effects are due to increased intracellular calcium, which raises myocardial oxygen demand and significantly increases the risk of arrhythmias. For example, even a 48-hour infusion of IV milrinone has been associated with more arrhythmias and hypotension compared to placebo. Therefore, current recommendations restrict the use of IV inotropes to patients with advanced HFrEF who develop cardiogenic shock, where they are used as short-term therapy to maintain systemic perfusion and end-organ function. Long-term use is limited to inotrope-dependent patients, mainly as a bridge to heart transplantation, mechanical circulatory support, or for palliative care.

Drug

Initial Infusion Rate

Max Rate

Hemodynamic Effects

Dobutamine

2.5–5 μg/kg/min

20 μg/kg/min

CO, HR, SVR

Milrinone

0.25–0.375 μg/kg/min

0.75 μg/kg/min

CO, SVR

Dopamine

2–5 μg/kg/min

20 μg/kg/min

Dose-dependent



 Fluid & Sodium Management

  • Sodium restriction (≤2 g/day)
  • Fluid restriction (1.5–2 L/day if hyponatremia)
  • Strict I/O monitoring
  • Daily weights

Guidelines recommend screening all heart failure patients for iron deficiency

  • Very common: seen in 50–80% of ADHF patients, even without anemia

Definition of Iron Deficiency (HFrEF)

  • Ferritin <100 ng/mL
  • OR
  • Ferritin 100–300 ng/mL + TSAT <20%

Oral iron NOT effective give iron.v iron only in divided dose


REFERENCES

1.Irwin and Rippe’s Intensive Care Medicine 9th edition