Recommended Dose of Furosemide Infusion in Heart Failure
For patients with heart failure, the initial recommended intravenous furosemide dose should be 20-40 mg as a bolus, followed by continuous infusion at a rate not exceeding 4 mg/minute when needed. 1, 2
Initial Dosing Strategy
- In patients with new-onset acute heart failure (AHF) or those with chronic, decompensated heart failure not receiving oral diuretics, the initial recommended dose is 20-40 mg IV furosemide 2
- For patients on chronic diuretic therapy, the initial IV dose should be at least equivalent to their oral dose 2
- Furosemide can be administered either as intermittent boluses or as a continuous infusion, with dose and duration adjusted according to the patient's clinical status and response 2
Continuous Infusion Protocol
- When using continuous infusion, add furosemide to either Sodium Chloride Injection, Lactated Ringer's Injection, or Dextrose (5%) Injection after pH has been adjusted to above 5.5 1
- Administer as a controlled intravenous infusion at a rate not greater than 4 mg/minute 1
- Low-dose continuous infusion (typically starting at 5 mg/hour, with a maximum of 6-7 mg/hour) has been shown to be effective and safe in achieving diuresis 3
- For refractory heart failure cases, higher doses may be required, but should be administered cautiously with close monitoring 4, 5
Monitoring and Dose Adjustment
- Regular monitoring of symptoms, urine output, renal function, and electrolytes is essential during IV diuretic therapy 2
- Dose adjustments should be based on clinical response, with at least 2 hours between dose increases 1
- If a satisfactory response is not achieved within 1-2 hours after the initial dose, the dose may be increased 1
Special Considerations
- Patients with a higher pre-admission dose of furosemide (>80 mg/day) may have diuretic resistance, requiring higher initial doses and more careful monitoring 6
- Acid solutions or other parenteral medications must not be administered concurrently in the same infusion as they may cause precipitation of furosemide 1
- In patients with acute pulmonary edema, if a satisfactory response does not occur within 1 hour after the initial 40 mg dose, the dose may be increased to 80 mg injected slowly intravenously (over 1-2 minutes) 1
Pitfalls and Caveats
- Furosemide is a buffered alkaline solution with a pH of about 9, and may precipitate at pH values below 7 1
- Excessive diuresis can lead to electrolyte imbalances, particularly hypokalemia, which may require potassium supplementation or addition of spironolactone 4
- Renal function should be closely monitored, as acute kidney injury may develop in approximately 19% of patients, most commonly within the first 48 hours of therapy 3
- For patients with refractory heart failure, diuretic resistance may develop, requiring dose escalation or combination therapy with thiazide diuretics 4, 5