HYPERAMMONEMIA following ingestion of protein has been observed in both animals and humans after portacaval shunt. The rise in levels of ammonia in the systemic circulation has been attributed to direct passage of ammonia-rich portal blood into the vena cava without preliminary transit through the liver.1 The validity of this hypothesis was tested by comparing the response of a group of animals with portacaval shunt to the response of a group with portacaval transposition after intragastric administration of whole blood.
—Eight adult mongrel dogs weighing 10 to 15 kg (22 to 33 1b) were used. The following studies were performed prior to operation: fasting whole blood ammonia, blood urea nitrogen, (BUN), alkaline phosphatase, bilirubin direct and indirect, total serum protein, albumin and globulin, and sodium sulfobromophthalein (Bromsulphalein) retention. An end-to-side portacaval shunt was constructed. Animals were allowed five to seven days to recover from the operation
KIRSH MM, KNAPP W, NEILL SA, COON W, ZUIDEMA GD. Portal Systemic Shunting in Experimental Ammonia Intoxication. Arch Surg. 1965;91(4):640-642. doi:10.1001/archsurg.1965.01320160094022