milrinone: clinical use

Prescribing considerations

• Use requires an acute-care setting with haemodynamic and rhythm surveillance.
• Renal impairment prolongs elimination and increases exposure; assess renal function before and during treatment.
• Avoid using milrinone as a substitute for surgical relief of severe obstructive valvular disease or hypertrophic subaortic stenosis.
• The selected product is not recommended immediately after acute myocardial infarction because safety and efficacy are not established.
• In neonates and children, consider renal maturity, thrombocytopenia, intraventricular haemorrhage and patent ductus arteriosus risks.

Contraindications and cautions

• Hypersensitivity to milrinone or an excipient
• Severe hypovolaemia

Monitoring

• Blood pressure, heart rate, clinical response and continuous ECG
• Fluid balance, electrolytes and serum creatinine
• Haemoglobin and platelet count where clinically relevant
• Infusion site for inflammation or extravasation
• In neonates after cardiac surgery, detailed haemodynamic, renal, hepatic, potassium and platelet assessment

Clinical pharmacology

Milrinone selectively inhibits phosphodiesterase-3 in cardiac and vascular muscle, producing positive inotropy, vasodilation and improved ventricular relaxation with relatively little direct chronotropic activity. It is eliminated mainly through the kidneys, making renal function an important determinant of exposure.

Formulation and product differences

• The selected product is a clear, colourless to pale-yellow intravenous solution supplied in glass ampoules.
• Compatible diluents specified in the selected SmPC include sodium chloride solutions and glucose solution.
• The solution is incompatible with sodium bicarbonate and must not share an intravenous line with furosemide or bumetanide.
• Prepared solutions should be visually inspected for particles or discolouration.

Injection

Route: Parenteral

Strengths: 1 mg/mL