Fluid therapy in critical illness: a special focus on indication, the use of hydroxyethyl starch and its different raw materials.

PURPOSE OF REVIEW: Fluid therapy is a complex intervention with insufficient resuscitation, as well as overinfusion and fluid accumulation being associated with adverse outcomes. Early goal-directed therapy with later conservative fluid management (i.e. prevention of positive fluid balance and weight gain) appears to markedly improve the survival of patients with severe sepsis. The impact of colloids in resuscitation of patients with sepsis has been the topic of several recently published studies. The purpose of the present review is to outline the indication of fluid administration in critically ill patients, discuss the recent findings of trials involving hydroxyethyl starch (HES) solutions and highlight the impact of different raw materials for HES synthesis.

RECENT FINDINGS: Pragmatic trials of modern HES solutions versus crystalloids in critically ill patients show either no difference or adverse outcomes associated with HES infusion. However, fluid therapy was not protocolized in most of these studies and probably associated with overinfusion and hemodilution. Data on the use of waxy maize-derived 6% HES 130/0.4 during early goal-directed therapy show no evidence for harm and an improvement in microvascular blood flow. In addition, experimental data suggest that waxy maize-derived 6% HES 130/0.4 may have different biological effects compared to potato-derived 6% HES 130/0.42 with potentially reduced pulmonary inflammation.

SUMMARY: Adverse effects of fluid resuscitation in critically ill patients appear to be a consequence of dose and timing rather than the type of fluid itself. Modern waxy maize-derived 6% HES 130/0.4 may have advantages over crystalloids in the very early course of the disease. Clinical trials of early, goal-directed and protocolized therapy with innovative endpoints of resuscitation comparing balanced crystalloids and balanced, waxy maize-derived 6% HES 130/0.4 as the initial resuscitation fluid are warranted.