THE OPERATIONS of portacaval anastomosis and hepatic artery ligation are predicated upon the fact that these procedures, by diverting blood from the liver, lower the pressure in the portal system and in the varices which have formed in that system. While it is easy to demonstrate at operation that there is an immediate fall in pressure in the portal vein following either procedure, there has been some question concerning the length of time that the pressure remains lowered, since it has been demonstrated repeatedly in the experimental animal that these efforts at diversion of blood are compensated by an increase in flow through collateral systems.
Some assistance in the solution of this problem was obtained when, in 1951, Meyers and Taylor1 demonstrated that by occlusion catheterization of an hepatic venule one could obtain a reasonably accurate estimation of the portal venous pressure. They showed that in 12 normal patients