Estimation of surgically manipulated fluid shear stresses in the abodminal vessels of swine from measured femoral artery flows

摘要

In support of an in vivo investigation in swine of the influence of changes in fluid dyamic wall shear on arterial macromolecular permeability, a procedure has been developed to alter the flows in the porcine posterior arterial vasculatore by opening and closing a reversibe arteriovenous shunt placed on oe of the femoral arteries. laparoscopic techniques were used to place appropriately modified ultrasonic flow probles on both external and circumflex iliac arteries, and on the terminal aorta. Flow measurements were made prior to shunt placement, and with the shunt open and closed, to measure the influence of altered external iliac artery flow on the distribution to the infrarenal abdominal vessels. Similar experiments were carried out to relate the flow rates in the external iliac arteries to those in the femoral arteries, which are more accessible. These results permit reasonable estimates to be made of infrarenal hemodynamics in the pig, at baceline and with the shunt opended or closed, from only the flow rates measured at the two femoral arteries. These estimates can then form the basis for global or detailed descriptions of shear stress distributions in the abdominal vessels.