Coagulation Effects of Hydroxyethylstarch Versus Modified Fluid Gelatin When Used as Normovolemic Hemodilution Solutions During Cardiac Surgery

summary Objective: The aim of this study to examine the effects of hydroxyethyl starch and gelatin solutions used for acute normovolemic hemodilution on coagulation during coronary artery bypass surgery. Material and Method: Seventy-two patients undergoing elective coronary artery bypass graft surgery randomly received no hemodilution (control), or 6% HES 200/0.5 (n=24) or 4% gelatin solution (n=24) for acute normovolemic hemodilution before cardiopulmonary bypass. Thromboelastography parameters were measured before (T0) and after (T1) acute normovolemic hemodilution, and one (T2) and four (T3) hours after separation from CPB. Results: The R (reaction) time in HES was significantly longer than in controls at T(2) (p=0.03). The K (coagulation) values in group HES and GEL were significantly longer than in controls at T(2) and T(3) (p=0.02 and 0.03, respectively). Rapidity of clot formation (alpha angle) was significantly smaller in HES and GEL compared to controls (p=0.01 and p=0.02, respectively). Maximum amplitudes in HES and GEL were not significantly different than cont rols at T(2) (p=0.3 and 0.9, respectively). At T2, three patients in GEL (but none in HES) showed clotlysis at 30 min (p=0.1). GEL and HES received fewer units of erythrocyts compared to controls(p<0.001); however, use of fresh frozen plasma was not significantly different than in controls. Mediastinal blood loss was greater in group HES than in controls (p<0.05). Conclusion: Performing acute normovolemic hemodilution with HES and GEL solutions caused significant change in co agulation state by thromboelastography, reduced the need for errytrocyt. Regarding the increase in mediastinal chest drainage, we concluded that HES may not be safety in patients undergoing coronary surgery.