We have done volume flow measurements since 1984. We find them
extremely useful for the follow-up of infrainguinal arterial bypasses.
We look for a bypass flow rate to be high initially in the early
post-op period but then reach a steady-state somewhere around 6 months
post-op. We routinely perform reactive hyperemia and look for a least
a doubling in volume flow as an indicator of a healthy bypass.
What is really important to a patient's limb is not how fast the blood
is flowing but how much blood (oxygen) is getting down to the tissue.
Remember, we don't pay for gasoline by how fast it comes out of the
pump but rather how many gallons (volume) we pump into our tanks.
Volume flows can vary significantly between machines. If you are
going to do volume flows, you must validate it in you own lab with a
proper phantom. There can be a lot of variability but by being
careful, this can be limited. We have measured volume flow in
dialysis grafts, renal transplants, radial arteries, native lower
extremity arteries, and ICAs. Much of it has been for research
purposes but it is part of our standard protocol for bypasses and
Ann Marie Kupinski
Karmody Vascular Lab