Colloids in critical illness

Colloid solutions are homogenous mixtures of large molecules suspended in a crystalloid solution. The efficacy of colloids as volume substitutes or expanders, and length of effect are determined by their physicochemical properties. Smaller volumes of colloid than crystalloid are required for resuscitation. The primary use of colloids is in the correction of circulating volume. Rather than using fixed haemodynamic endpoints, fluid can be given in small aliquots with assessment of the dynamic haemodynamic response to each aliquot. The aim of a fluid challenge is to produce a small, but significant (200 mL) and rapid increase in plasma volume with changes in central venous pressure or stroke volume used to judge fluid responsiveness. Colloid fluids give a reliable increase in plasma volume to judge fluid responsiveness.

Blood Volume Substitutes in Emergency Care

Volume substitutes for restoring circulating blood volume are eminently important for emergency care. In addition to side effects, the intravascular volume effect immediately after infusion and the duration of this volume effect are determining factors for the selection of volume replacement solutions available on the market today. Therefore, we controlled the intravascular volume effect of 16 test solutions, immediately as well as 90 and 240 min after the end of infusion.