CONGESTION OF THE LIVER 233 



intestinal mucosa, sodium bicarbonate (dog, 0.5-1.0; cat, 

 0.2-0.8) given three to four times daily is beneficial. Am- 

 monium chlorid (dog, 0.5-1.2; cat, 0.2-0.5) given three times 

 daily will assist in the excretion of the urea, uric acid, etc., 

 and relieve the intestinal catarrh. During convalescence 

 bitter stomachics are indicated to stimulate secretions and to 

 assist in digestion. Intestinal antiseptics, such as salol, are 

 also often indicated. 



Passive Congestion.— Definition.— A congestion of the liver 

 due to some impediment in the efferent circulation of the 

 blood in the liver. 



Etiology.— This condition may result from the following: 

 (a) Defective heart action, whether it be acute or chronic, 

 such as valvular insufficiencies, (b) During the course of 

 some diseases of the lungs which increase the work of the 

 right side of the heart, eventually weakening it. Examples 

 are emphysema, chronic bronchitis (common in old dogs), 

 compression by pleural exudates, adhesive pleuritis, tumors of 

 the mediastinum, etc. (c) Local obstructions to the circula- 

 tion of blood through' the hepatic veins and posterior vena 

 cava. The most common are: Pleural or peritoneal effu- 

 sions (when in large quantities, displacing the heart or com- 

 pressing the veins), tumors of the liver (carcinomas and 

 sarcomas in older animals), adhesions around the liver from 

 abdominal operations, injuries, etc. 



Pathology. —The congested liver in the early stages is 

 somewhat increased in size, depending upon the amount of 

 blood contained. The organ is firm, dense and of a bluish 

 or dark purple color. 



Cut section shows a more or less uniformly congested, 

 dark-blue or purplish color, and presents a mottled appear- 

 ance with light areas. In the advanced stages there is an 

 excess of blood, and the liver presents the characteristics 

 of the "nutmeg" liver; the intralobular and sublobular 

 venules being distended and filled with blood, appearing as 

 dark blue, purplish or reddish spots, while the liver cells are 

 pale yellowish, or whitish, showing fatty infiltration and 

 biliary pigmentation, which gives the marked contrast in 

 color ("nutmeg" liver). In the most advanced stages, the 



