Volume replacement in trauma.

We aimed to compare different fluids indicated in volume replacement in multiple trauma patients, enlightening the indications, mechanisms of action and side effects. An extensive review of references (indexed journals) between 1997 and 2008 was performed. There is not yet a consensus about which fluids should be used in trauma patients. The systematic reviews available did not show a benefit of colloid solutions over crystalloid fluids. Crystalloids intensify physiological internal dilution, furthered by water migration from interstitial and intracellular spaces into intravascular space due to hypovolemia. The most recent hypertonic solutions used in resuscitation have a large role in expanding blood volume and making blood pressure rise. The hyperoncotic effect of dextran solution produces an initial expansion of intravascular volume that is bigger than the administered volume. Gelatins are no longer used in developed countries due to their insignificant ability regarding volume expansion when compared to crystalloids and the potential risks of anaphylactic reactions. The crystalloids are used more in trauma, even if some authors prefer the use of colloids, which can produce a quicker restoration of the intravascular volume. No convincing evidence shows a clear superiority of colloids over crystalloids for restoration of the volume depletion.