Rationale for the use of colloids in the treatment of shock and hypovolemia.

The question, "Are colloids or crystalloids to be preferred for resuscitation in hypovolemic shock conditions?" is detailed in this review. The effects of these two types of fluid regimes on restitution of circulating blood volume, interstitial rehydration, microvascular blood flow, cellular metabolic recovery and on the incidence of systemic complications such as adult respiratory distress syndrome (ARDS), disseminated intravascular coagulation (DIC) and multiple organ failure are considered. Colloid containing solutions seem superior to crystalloids due to efficient reexpansion of circulating blood volume and enhancement of capillary blood flow. Resuscitation times and thereby the cellular hypoxic insult are considerable reduced while at the same time the formation of excessive tissue oedema is prevented. Colloids do not seem to adversely affect pulmonary function. Dextran has considerable advantages over other types of colloids for the initial shock treatment due to its antithrombotic properties whereby cell aggregability is prevented and the incidence of systemic complications (microembolism syndromes) is convincingly reduced.