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PubMed · 7598278

Heparin neutralization by recombinant platelet factor 4 and protamine.

J H Levy·J G Cormack·A Morales
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Abstract

Protamine is the only available drug to reverse heparin-induced anticoagulation. Platelet factor 4 (PF4) is a basic polypeptide stored in platelets that reverses heparin. To investigate its potential as a reversal drug, we studied recombinant PF4 on anticoagulated blood obtained during cardiac surgery. Blood was obtained from 33 different venous reservoirs, and activated clotting time (ACT), heparin concentrations, and heparinase-ACT were determined. Anticoagulation was reversed by adding incremental PF4:heparin and protamine:heparin ratios to the heparinized blood, and the ACTs were determined (n = 21). Viscoelastic analysis of anticoagulation reversal was performed by adding protamine or PF4 at reversal ratios of 1.3:1 protamine:heparin, and 3.2:1 PF4:heparin using thromboelastography (n = 12). PF4 reversal ratios of 3:1 and 3.5:1 and protamine reversal ratios of 1:1, 1.5:1, 2:1 were not statistically different from heparinase-ACT values. There were no significant differences in viscoelastic measurements of clot formation between protamine and PF4. Recombinant PF4 at a 3.0:1 ratio reverses heparin-induced anticoagulation after cardiopulmonary bypass, and represents a potential alternative, especially for the protamine allergic patient.

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Blood CoagulationBlood PlateletsBlood ViscosityCardiac Surgical ProceduresCardiopulmonary BypassDose-Response Relationship, DrugElasticityFibrinogenHeparinHeparin AntagonistsHeparin LyaseHumansPlatelet Factor 4Polysaccharide-LyasesProtaminesRecombinant ProteinsThrombelastographyWhole Blood Coagulation TimeComparative StudyJournal Article

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J H Levy, J G Cormack, A Morales. 1995. Heparin neutralization by recombinant platelet factor 4 and protamine.. https://doi.org/10.1097/00000539-199507000-00007

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