Usual Dosage of Milrinone Drip
The usual dose of milrinone drip consists of a loading dose of 50 mcg/kg administered over 10 minutes, followed by a maintenance infusion of 0.375-0.75 mcg/kg/min, with a standard dose of 0.5 mcg/kg/min and a maximum dose not exceeding 1.13 mg/kg/day. 1, 2
Dosing Protocol
Loading Dose
- 50 mcg/kg administered slowly over 10 minutes 1
- May be given undiluted or diluted to a total volume of 10 or 20 mL for easier visualization of injection rate 1
- Loading dose range per guidelines: 25-75 μg/kg over 10-20 minutes 2
Maintenance Infusion
- Minimum: 0.375 mcg/kg/min (0.59 mg/kg total daily dose) 1
- Standard: 0.5 mcg/kg/min (0.77 mg/kg total daily dose) 1
- Maximum: 0.75 mcg/kg/min (1.13 mg/kg total daily dose) 1
Preparation and Administration
- Milrinone should be diluted prior to maintenance dose administration 1
- Appropriate diluents include:
- 0.45% Sodium Chloride Injection USP
- 0.9% Sodium Chloride Injection USP
- 5% Dextrose Injection USP 1
- Standard concentration for infusion: 200 mcg/mL 1
Dosage Adjustment in Renal Impairment
Renal impairment significantly increases the terminal elimination half-life of milrinone, requiring dose adjustments 1:
| Creatinine Clearance (mL/min/1.73m²) | Recommended Infusion Rate (mcg/kg/min) |
|---|---|
| 5 | 0.20 |
| 10 | 0.23 |
| 20 | 0.28 |
| 30 | 0.33 |
| 40 | 0.38 |
| 50 | 0.43 |
Monitoring Requirements
- Continuous ECG monitoring during infusion and for 1-2 hours after discontinuation 2
- Daily laboratory monitoring of electrolytes, BUN, and creatinine 2
- Hemodynamic monitoring to assess response 2
- Infusion rate should be adjusted according to hemodynamic and clinical response 1
Clinical Considerations
- Milrinone is indicated for short-term intravenous treatment of patients with acute decompensated heart failure, particularly those with:
- Low cardiac output states
- Evidence of end-organ hypoperfusion
- Systolic blood pressure >90 mmHg 2
- Milrinone produces significant hemodynamic improvements through:
- Increased cardiac contractility (21-38% increase in cardiac index)
- Peripheral vasodilation (13-41% decrease in pulmonary capillary wedge pressure) 2
- Maintains effectiveness in patients on beta-blocker therapy 2
Important Precautions
- Not recommended for routine use in normotensive patients without evidence of decreased organ perfusion 2
- Use with caution in patients with coronary artery disease due to potential increased medium-term mortality 2
- Major adverse effects include hypotension, ventricular arrhythmias, and thrombocytopenia 2
- Gradual tapering is essential to prevent hemodynamic deterioration 2
- Facilities for immediate treatment of potential cardiac events must be available 2