Hydroxyethyl starch solutions and their effect on the microcirculation and tissue oxygenation

SUMMARY The main goal of ideal fluid therapy is not only to maintain systemic circulation, but also to restore tissue perfusion and oxygen delivery to the tissues and specifically to the microcirculation where oxygen delivery takes place. For this purpose, various kinds of crystalloid and colloid solutions are being used. The ongoing debate about the use of crystalloid versus colloid solutions has now shifted to a debate on the ideal type of colloid solution. Hydroxyethyl starch (HES) is one of the most studied plasma substitutes. Different kinds of HES solutions exist worldwide, which differ greatly in their pharmacological properties. Low-molecular-weight HES solutions have been successfully and safely used for intravascular volume therapy, and also to restore hemodynamic, microcirculatory and cardiorespiratory function. This article reviews their effect on the microcirculation and tissue oxygenation.