Severe hemodilution with hydroxyethyl starch and dextrans. Effects on plasma proteins, coagulation factors, and platelet adhesiveness.

DEXTRANS have been in clinical use as plasma expanders for a number of years. Following large infusions, hemorrhage is not infrequent and numerous investigations of the effects of dextrans on blood coagulation factors and hemostatic mechanisms have been made.1-9One consistent finding has been a prolongation of the bleeding time which seemed out of proportion to the reduction in platelet count. Other findings include reductions in various coagulation factors (which may exceed those anticipated for simple dilution) and an inhibitory effect on the release of platelet thromboplastic factor (platelet factor 3). The experiments performed by Takaori and Safar10,11offered an opportunity to reexplore the effects of massive infusions of clinical dextran and to compare the effects of dextran 40 and an experimental plasma expander: hydroxyethyl starch (HES). Methods Coagulation factors were measured by previously described methods.12,13Hematocrit reading and sedimentation rate were measured by Wintrobe's methods.14