Effects of Acute Hypervolemic Hemodilution on Hemorheology

Objective:To observe the changes of hemorheology after acute hypervolemic hemodilution (AHH) in clinical practice.Methods:60 patients for selected spinal surgery were randomly divided into 3 groups (n=20) to receive intravenous infusion 20 ml/kg of 6% hydroxyethyl strach (HES)(H group),4% gelofusine(G group) or ringer's solution(R group),respectively,before surgery. The whole blood viscosity,plasma viscosity, Hct,index of RBC aggregation and index of RBC deformation were measured before and after hemodilution.Resutls:①Hemodynamics were stable after hemodilution, the amounts of blood transfusion perioperatively inthe colloid(H,G) group patients were less than that in the crystalloid (R)group;②The whole blood viscosity, Hct and index of RBC aggregation were significantly reduced after AHH in all patients;Index of RBC deformation was markedly increased in patients after AHH by 6% HES.Conclusion:AHH could effectively maintain hemodynamic stablity, improve the hemorheological status and microcirculative perfusion, enhance the tolerance of blood loss, and reduce homologous blood transfusion. Colloid could be better than crystalloid for AHH.