comparative evaluation of the effects of hydroxyethyl starch on coagulation state of patients during brain tumor surgeries in comparison to crystalloids by thromboelastography

background:: hypercoagulability has been reported in primary brain tumors which can lead to thrombotic complications.hydroxyethyl starch (hetastarch) is a synthetic colloid solution with adverse effects on blood coagulation. the aim of this study was to evaluate the protective effect of hetastarch in reducing thromboembolic events in these patients. materials and methods: in a double-blinded clinical trial, 60 brain tumor surgery patients were randomly divided into two groups and given 10 ml/kg hetastarch or normal saline during surgery. blood coagulation was compared before and after infusion of these fluids within and between groups by thromboelastography (teg). results: there were no significant differences in bleeding (p = 0.126), duration of surgery (p = 0.504), and fluid intake (0.09l) between the two groups. percentage of changes in r (r: time to initiate fibrin formation), k (k:measure of the speed taken to reach a specific level of clot strength), and ly30 (ly30: percent of fibrin distraction after 30 minutes of clot formation) in the crystalloid group were –20.61 ± 26.46, –30.02 ± 49.10, and 1.27 ± 22.63, and that in the colloid group were 22.10 ± 26.11, 41.79 ± 37.15, and 59.09 ± 37.12, respectively. deterioration in hemostasis during and after surgery was not observed. conclusion: there was a reduction in the speed of clot formation and increase in clot lysis in the hetastarch group. coagulability was decreased in the colloid group. infusion of 10 ml/kg hetastarch in brain tumor resection surgeries can probably decrease susceptibility of these patients to deep vein thrombosis (dvt) and thromboembolic events.