Effect of raised portal venous pressure on blood pressure, urine output and body fluids.

Acute rise of portal venous pressure resulted in a fall of blood pressure and subsequent anuria which could be either due to the state of shock or may be reflex in origin. There also occurred an increase in extra-cellular fluid volume with an initial increase in both plasma volume and interstitial fluid volume. Subsequently the extra-cellular fluid volume remained at a high steady value whereas the plasma volume increased at the expense of interstitial fluid volume which decreased. It is further postulated that the rise of extra-cellular fluid volume is due to the shift of fluid from intra-cellular compartment of the extra-cellular compartment, as a defence mechanism to combat the state of shock.