MILRINONE (Primacor)

 

Name: MILRINONE (PrimacorR)
Classification: inotropic agent (phosphodiesterase inhibitor)
  • increases contractility (inotrope) and cardiac index
  • lowers capillary wedge pressure
  • lowers pulmonary artery pressure
  • increases the rate of myocardial relaxation (lusitropic effect)

Used for short-term management of heart failure.

Dose:
  • Loading Dose:
    • 50 mcg/kg IV over 10 minutes
    • Administer loading dose from the infusion bag; programme the infusion pump to deliver the bolus dose over 10 minutes
  • Maintenance Infusion:
    • 0.375-0.75 mcg/kg/min, adjusted to cardiac index, venous oxygen saturation or other marker of cardiac output
    • dose reduction required in renal dysfunction (e.g. infusion rate starting at 0.2 mcg/kg/min)
  • Maximum Daily Dose:
    • 1.13 mg/kg (including boluses)
Administration: IV Infusion:
50 mg in 250 ml dextrose 5%, normal saline 0.9% or Ringer's Lactate (0.2 mg/mL)
  • hypovolemia, acidosis and hypoxemia should be corrected concurrently with therapy
Contraindications:

Hypersensitivity to milrinone or its components.

Cautions:

  • Use with caution in patients with uncontrolled atrial fibrillation/flutter as will enhance AV node conduction; consider digitalizing these patients first
  • Dose adjust in renal failure
  • Long half life can result in prolonged vasodilatory effect 
Adverse Effects:
  • Tachycardia, arrhythmias (supraventricular and ventricular)
  • Hypotension
  • Headache
  • Hypokalemia
  • Thrombocytopenia 
  • Tremor
  • Bronchospasm
Monitoring Therapy:
  • Continuous heart rate and ECG rhythm
  • Blood pressure
  • Hourly urine output
  • Central or mixed venous oxygen saturation
  • Lactate
  • Cardiac index if available
  • SVRI if monitored
  • Platelet count
Adult Critical Care Protocol:
  • May be administered by IV infusion by a nurse in Adult Critical Care
  • Each loading dose and infusion rate must be ordered by physician; nurses are not approved to titrate milrinone or administer a bolus
  • Administration via a central venous access device is preferred
  • Continuous infusions must be administered by infusion device and the pump library must be enabled.
  • Should not be infused via the proximal injectate port (blue) of a pulmonary artery catheter. If this is the only available central venous line, it may be administered through the proximal injectate port but thermodilution cardiac output measurements must not be measured during infusion).


Lynne Kelly, Pharmacist, CCTC
Brenda Morgan, Clinical Nurse Specialist, CCTC
Last Update: January 12, 2017; Revised March 27, 2017, updated September 17, 2018; February 13, 2023 (BM)