In order to test the ability of solutions of concentrated serum to lower cerebrospinal pressure under more accurately controlled conditions than was possible in a clinical study (Hughes, Mudd and Strecker1), further experiments have been performed on dogs. In these experiments the cerebrospinal fluid pressure was recorded continuously after cisternal puncture. The animals were anesthetized with sodium amytal. Dog serum, concentrated four times by dissolving the dried serum in water to make one-fourth its original volume, was used.2 Observations were made as controls on the cerebrospinal pressure in all experiments for periods of from two to three hours before the injection of the hypertonic solution. These prolonged observations were made as controls because of the fluctuations in pressure which occur during the early periods of sodium amytal narcosis. The data on these experiments are presented in the accompanying table.
RESULTS
A fall in cerebrospinal pressure occurred in each