A New Liver Function Test.

Abstract

In a number of phenoltetrachlorphthalein liver function tests, determinations of the bilirubin content of the blood showed a rise of the icterus index following the intravenous injection of the dye. When bromosulphalein was used no rise in the index took place. At first the reason for the rise in index following the use of the phenoltetrachlorphthalein was thought to be its toxic action upon the liver. Dr. S. M. Bassett, however, suggested that, inasmuch as distilled water was used to dilute a 5% to a 1% solution in the case of phenoltetrachlorphthalein, and no dilution was made in the case of bromsulphalein, the increase in icterus index might be due to the laking of red blood cells by the distilled water. Accordingly injections of distilled water up to 100 cc. were given intravenously, and, as surmised, a rise in the icterus index was produced.

From this observation the idea arose that this use of distilled water might serve as a liver function test. The rationale was as follows: if the normal liver removes bilirubin from the blood (the source of bilirubin being the hemoglobin from destroyed red blood cells), it is reasonable to suppose that a disordered liver will remove it less efficiently. If, then, in the normal person after the injection of distilled water the icterus index rises from 2 to 4 points one half hour to an hour after injection, with an average rise of 2.5 points, and returns to its basal value in 5 hours, a greater increase in icterus index might conceivably be expected in the individual with a disordered liver, or the return to normal might be prolonged.

Adequate dosage of the water was ascertained by experiment. 25 cc. are used in the case of individuals weighing from 100 to 110 pounds, with an increase of 5 cc. for every pound of body weight up to a maximum dosage of 50 cc.