Hematology tests of blood anticoagulated with magnesium sulphate.

Venous blood treated with magnesium sulphate (MgSO4) at blood collection was used for hematology tests. Complete blood counts and automated leukocyte differentials were obtained using a hematology analyzer, and the results obtained for blood treated with MgSO4 were similar to those for blood treated with dipotassium ethylenediaminetetraacetic acid (EDTA K2). Coagulation tests such as activated partial thromboplastin time, platelet factor 3 availability and prothrombin time were dose-dependently affected by the use of MgSO4. Thrombin time was prolonged by addition of MgSO4, and fibrin concentrations determined by coagulometry tended to decrease with addition of MgSO4, although fibrin concentrations determined by the weighing method were unaffected by MgSO4. MgSO, was thus found to potently inhibit blood coagulation and can be used as an anticoagulant for hematology tests.