Maize‐ or potato‐derived hydroxyethyl starches: is there any thromboelastometric difference?

Background: Hydroxyethyl starches (HES) could differ with regard to the origin, and the influence on the coagulation of the raw material is unknown. This study compared the effects of a new potato‐derived HES with a maize‐derived HES and two crystalloid solutions. Methods: Whole blood from 10 healthy individuals was diluted by 20% and 40% using either non‐balanced potato‐derived HES 130/0.42/6 : 1, non‐balanced maize‐derived HES 130/0.4/9 : 1, isotonic saline or Ringer's lactate solution. Samples were analysed by thromboelastometry ROTEM ® : Coagulation was initiated by acid ellagic [intrinsic thromboelastometry (INTEM)] or tissue factor (extrinsic thromboelastometry) with and without cytochalasin to determine the functional component of fibrinogen [cytochalasin‐ d ‐modified thromboelastometry (FIBTEM)]. Platelet count and fibrinogen activity were measured. Results: No effect of raw material was found as no difference was detected among the HES solutions. Whatever the solution, progressive haemodilution impaired haemostasis in a dose‐dependant manner: For INTEM, the clot formation time was increased up to 308% and the maximum clot firmness (MCF) was decreased down to 49%. As dilution increased, initiation of coagulation was also impaired. Thromboelastometric alterations were more severe with HES than with crystalloids, especially regarding fibrin polymerization explorations: MCF of FIBTEM was considerably reduced from 12[10–14] to 2[2–3] mm ( P <0.05). Fibrinogen activity and platelet count were reduced by dilution in a dose‐dependant manner and decreased similarly in all groups. Conclusion: Maize‐ and potato‐derived HES have similar effects on coagulation. Both the starch preparations tested lead to more severe haemostatic defects than crystalloids, and impairment of fibrin polymerization appears to be a leading determinant of this coagulopathy.