Impact of hetastarch on the intestinal microvascular barrier during ECLS

The effects of hetastarch on microvascular fluid flux were determined in an esthetized dogs undergoing extracorporeal life support (ECLS) with a roller pump and membrane oxygenator. ECLS with a lactated Ringer priming solution resulted in a decrease in microvascular protein reflection coefficient and an increase in transvascular protein clearance. Use of a 6% hetastarch pri ming solution attenuated the decrease in microvascular protein reflection c oefficient; and blunted the increase in transvascular protein clearance. Il eal. tissue water increased in the group treated with the lactated Ringer p riming solution compared with the group treated with 6% hetastarch. The eff ective plasma-to-interstitial colloid osmotic pressure gradient was greater in the group treated with hetastarch than in the group treated with lactat ed Ringer solution. Hetastarch decreases the edema associated with ECLS. Th e reduction in edema is due to the maintenance of the plasma-to-interstitia l colloid osmotic pressure gradient and the reduction in the microvascular permeability to protein.