[Use of colloids in acute hypovolemia]

In Denmark several natural and synthetic colloids are available. Natural colloids are fresh frozen plasma (FFP) and human albumin (HA). Both are ideal as plasma expanders, but FFP can carry infectious agents and HA is quite expensive. The synthetic colloids or modified macromolecules are the dextrans (Macrodex (MD) and Rheomacrodex (RMD)), Haemaccel (HC), and Haes-steril (HS) in 6 and 10% solutions. HC has few indications because of a questionable volume expansion and a relatively high frequency of side effects. RMD is useful in cases of compromised regional blood flow. HS 10% and HA 20% are hyperoncotic and are effective in redistributing interstitial fluid to the intravascular space. HS and MD are both effective as volume substitutes. In addition HS and MD have beneficial side effects such as an inhibition of erythrocyte aggregation and inhibition of leucocyte marginalisation. Furthermore, MD has an anti-thrombotic effect. However, MD has in contrast to HS a dose dependent effect on the bleeding time. HS and MD are effective in restoring the colloid osmotic pressure and can in many cases replace HA in treatment of hypovolaemia.