An investigation into the risk of air embolus during veno-venous bypass in orthotopic liver transplantation.

After observing micro-bubble activity in the venovenous bypass system during liver transplantation, an experiment was designed to investigate the origin of these bubbles and to define the conditions under which they occurred. Using a Biomedicus constrained vortex pump and a customized circuit design, microbubble activity was measured in saline and blood media during varying pre- and post-head pressures. The data show that air emboli can be generated from this pump and the rate at which they develop is directly related to the pre- and post-head pressure and hematocrit.