A Diaphragmatic Hernia in a Cat

Patient Information

Age: 4 years old

Gender: Spayed Female

Species: Feline

Breed: Domestic Medium Hair

History:

A 4 year old female spayed domestic Medium hair cat presented with a 1 month history of vomiting and decreased appetite. She was not known to chew or ingest inappropriate items.

Ultrasound Findings:

No hepatic tissue is noted left cranial abdomen. It appears that the left liver lobes are deviated to the right cranial abdomen, and the right liver lobes and gallbladder are appreciated in the mid to cranial right thorax (the gallbladder is of normal size, shape, and is clean).

Many well-defined, homogenous hyperechoic nodules measuring 0.6x0.5 cm are noted throughout the hepatic tissue within the thorax; no focal lesions are noted within the intra-abdominal liver. The visible liver retains normal shape and echogenicity; size could not be confidently evaluated.

Image Interpretation:

The findings are consistent with a diaphragmatic hernia; peritoneopericardial diaphragmatic hernia is not suspected.

Discussion:

A diaphragmatic hernia is the dislocation of abdominal contents into the thorax through a defect in the diaphragm. These can be acquired (trauma) or congenital (with PPDH being more common in congenital cases) in origin. Radiographs may be enough to diagnose a diaphragmatic hernia, though in some cases the degree of pleural effusion may prevent visualization of abdominal viscera within the thorax. Furthermore, in this case only a small section of the stomach and pylorus are thought to be involved, and if only liver were seen within the thorax, further diagnostics would have been required to confirm this as the cause of the patient's vomiting. In addition to ultrasound, contrast radiography or CT/MRI may be considered when necessary.

Possible sequalae include respiratory distress due to mass effect of involved organs and pleural effusion, entrapment and necrosis of viscera, tension gastrothorax (which can be acutely life-threatening), and poor intestinal function. PPDH may produce no signs (if a larger hernia which allows organs to move back and forth freely), or may result in reduced cardiac function, pericardial effusion, and arrhythmias. Clinical signs vary depending on severity and may include respiratory distress and other respiratory signs, cardiac signs such as arrhythmias, pale or cyanotic mucous membranes, as well as GI signs like vomiting, diarrhea, weight loss, inappetence, and even shock or acute death. With congenital disease, clinical signs may not be noted until later in life.

Surgery is the required treatment for diaphragmatic hernias. If necessary, the pet should be stabilized prior, and prophylactic antibiotics may be considered if there is herniation of the liver, due to potential for toxin release if there has been hepatic strangulation or vascular compromise. Possible surgical complications include increased intra-abdominal pressure if the DH is chronic, or pulmonary edema secondary to re-expansion. Bella the cat has surgery scheduled in July.