Dog - Rupture of the Diaphragm

What is the diaphragm?

The diaphragm is the muscular partition which separates the abdomen from the chest. Tearing or disruption of this partition is a diaphragmatic rupture. The term can be used interchangeably with diaphragmatic hernia, but has a rather wider meaning in that some forms of diaphragmatic hernia, such as Peritoneal-pericardial diaphragmatic hernia, PPDH, are congenital and may be due to error during development of the diaphragm in the womb. This condition however is very rare and should be considered separately from the traumatic type of diaphragmatic rupture.

What causes rupture of the diaphragm?

The most common cause is severe trauma such as occurs when a dog falls from a height or is involved in a road traffic accident.

What are the symptoms?

In the case of traumatic diaphragmatic rupture signs will depend on the severity of the injury and the possibility of injury of other organs resulting in potential complications.

The major signs are usually acute shock and respiratory (breathing) distress. This can be due to abdominal organs passing through the tear in the diaphragm into the chest cavity. This restricts the space available for the lungs to inflate and therefore affects breathing. In addition the lungs themselves may be injured at the time of the accident, adding to the breathing problems. Injuries to the heart muscle (myocardial injury) may result in an irregular heartbeat. In addition any abdominal organs within the thorax can become trapped, resulting in strangulation of their blood supply. This in turn can lead to circulatory problems and further complications.

Breathing can vary from shallow, rapid respiration, to that with a typical increased abdominal respiratory effort. Sometimes respiration may appear normal immediately following the accident despite obvious severe trauma. This can occur on occasions when the diaphragm is ruptured but there has been no migration of abdominal organs into the chest cavity.

It is for this reason that chest radiographs (x-rays) are often routinely taken in order to establish the extent of any injury following any form of severe trauma involving the body cavities.

Blue colour of the mucous membranes (cyanosis) is also associated with diaphragm rupture. This indicates that due to breathing difficulties the blood and therefore the tissues are not being adequately oxygenated.

Are these signs always present immediately following the injury?

The rapidity with which symptoms develop depends upon the severity of the tear in the diaphragm and the rapidity with which the abdominal organs move into the chest cavity. Signs also depend upon the abdominal organs involved. If, for example, the stomach moves into the chest area (gastric herniation) in this position the stomach can rapidly fill with air (bloat) and a separate emergency situation can rapidly develop.

On the other hand if the diaphragm has ruptured but there has been no herniation of abdominal contents, days may pass before obvious signs are recognised.

How is diaphragmatic rupture diagnosed?

Diagnosis is usually based on a history of recent trauma, difficulty in breathing (dyspnoea) together with signs such as cyanosis (blue gums), exercise intolerance, shock, irregular heartbeat, etc.

Confirmation of diagnosis depends on radiography (xrays), sometimes involving special techniques such as the use of oral barium or special dye (contrast radiography). Ultrasound scans are sometimes used to confirm diagnosis.

What is the treatment?

Surgical correction of diaphragm damage is the standard method of treatment. It does carry some risk particularly in respect of the anaesthetic. It is important that the patient is stabilised and any lung or heart injuries are treated. Often this may take a few days but can result in less complications during and following surgery.

If the patient stabilises with this treatment, is it possible to avoid surgery?

After approximately seven days adhesions may form between the lungs and any herniated abdominal contents, this means that the abdominal organs will stick to the lungs and chest wall. This can result in further complications making surgery more difficult as it's harder to return the abdominal organs to the abdomen if they're stuck in the chest! Each case has to be assessed individually.

What is the outlook following surgery?

Dogs with diaphragmatic rupture are high risk patients. In addition they may have other injuries which significantly increase the surgical risk. However once the patient is stabilised surgery is the rational option and if successful can result in return to normal activity in a relatively short time.

If you have any queries or concerns, please do not hesitate to contact us.