Protamine

Protamine - available as a 1% (10 mg/ml) solution of protamine sulphate.Although it is used to neutralise the anticoagulant action of heparin and LMWH, if used in excess it has an anticoagulant effect.

Uses
Neutralise the anticoagulant action of heparin and LMWH

Contraindications
Hypersensitivity

Administration
1 ml 1% (10 mg) protamine is required to neutralise 1000 units of heparin given in the previous 15 min
As more time elapses after the heparin injection, proportionally less protamine is required
Slow IV injection 5 ml 1% over 10 min
Ideally, the dosage should be guided by serial measurements of APTT/ACT and the rate guided by watching the direct arterial BP

How not to use protamine
Rapid IV bolus

Adverse effects
Hypersensitivity
Rapid IV administration – pulmonary vasoconstriction, ↓ left atrial pressure and hypotension

Cautions
Hypersensitivity (severe hypotension, may respond to fluid loading)