Heparin

We recommend that severe bleeding associated with intravenous unfractionated heparin (UFH) should be treated with intravenous protamine at a dose of 1mg per 100 IU UFH given in the preceding 2 to 3 h. 1A

We suggest that severe bleeding associated with subcutaneous (SC) UFH unresponsive to intravenous protamine at a dose of 1mg per 100 IU UFH could be treated by continuous administration of intravenous protamine, with the dose guided by aPTT. 2C

We suggest that severe bleeding related to SC low molecular weight heparin (LMWH) should be treated with intravenous protamine at a dose of 1mg per 100 antifactor Xa units of LMWH administered and, if unresponsive, with a further 0.5mg protamine per 100 antifactor Xa units. 2C