USE OF PARA-AMINO HIPPURIC-ACID TO MEASURE BLOOD FLOWS THROUGH PORTAL-DRAINED-VISCERA, LIVER AND HINDQUARTERS IN SHEEP

The objectives of this study were (i) to evaluate a new surgical proce dure to catheterize hepatic vessels as well as the posterior aorta and vena cava, (ii) to test a modification of a downstream dilution techn ique in order to measure blood flows through splanchnic tissues and hi ndquarters in rapid succession, and (iii) to improve the reliability o f splanchnic blood flow measurements using para-amino hippuric acid (P AH). Ten adult ewes were used. The transhepatic surgical approach used proved successful; it was relatively easy to set up and a good recove ry of hepatic functions was obtained. The attempt to measure splanchni c and hindquarters blood flow in rapid succession by alternating the s ites of PAH infusion was unsuccessful, probably because of transient m odifications in infusion rates due to different blood pressures in vei ns and arteries. Indeed, arterial PAH concentrations changed with infu sion site. Finally, a better reproducibility of splanchnic blood flow measurements was obtained in sheep, fed every 3 h, by infusing the req uired amount of PAH partly via the mesenteric vein and partly via a ru minal vein.