LUNG FUNCTION STUDIES AFTER THE INTRALYMPHATIC INJECTION OF EMULSIONS OF ETHIODOL IN DOGS

Abstract

Originally we became interested in developing an emulsion of Ethiodol in an effort to speed up the procedure of lymphography. With the viscous Ethiodol 45 to 60 minutes are required for injection. Certain low viscosity emulsions can be prepared, allowing much more rapid introduction. These emulsions are equal or superior to Ethiodol in definition of lymphatic structure and certain of them are equally long retained in the nodes for long term radiographic studies (3).

The search for an emulsion takes on added importance since Ethiodol globules embolize in the lungs to greater or lesser degree when lymphography is performed in man or animal, the globules reaching the lungs via the thoracic duct or by lymphatico­ venous anastomoses. In most instances this is of no consequence but rarely a patient with concurrent lung disease or with lungs damaged by prior disease or radiation develops acute respiratory difficulties. Unassailable evidence of decrease in pulmonary diffusing capacity after lymphography has been obtained and this appears to be mainly due to a decrease in pulmonary capillary volume (5, 6). Pulmonary oil embolism ought not to occur if the particles of the emulsion are below the diameter of a lung capillary. Pulmonary function following lymphography with Ethiodol emulsions was therefore examined using the dog as an experimental animal.