Crystalloids versus colloids for fluid resuscitation in critically-ill patients.

The choice of crystalloid or colloid for fluid resuscitation has been debated for the last few years. Although colloids seems to be more interesting when taking into account their physiological properties, their effect on mortality is not better than crystalloids if they are used in an adequate amount. Moreover, colloids' side effects are far more important than those of crystalloids. Several randomised studies pointed out the renal effects of colloids including acute renal injury with an increased need of renal replacement therapy. An unacceptably high rate of renal side effects has resulted in premature termination of some clinical trials. In addition, homeostatic and anaphylactoid effects of colloids on coagulation and on anaphylaxis may increase the risk of death associated with their use. Finally, colloids are much more expensive than crystalloids. For all these reasons, we conclude that crystalloids should be preferred to colloids for fluid resuscitation.