Diaphragmatic Hernia in Cats

  • Author

  • At a glance

    About: A diaphragmatic hernia is a defect or tear in the diaphragm, which allows the abdominal contents to enter the chest cavity.Symptoms:

    • Difficulty breathing
    • Exercise intolerance
    • Lethargy

    Additional symptoms can occur if one or more of the abdominal contents enter the chest cavity.

    Diagnosis: History of recent trauma or fall and imaging to examine the internal organs and diaphragm.

    Treatment: Mild cases may require rest only; severe cases will need surgical repair.

    What is a diaphragmatic hernia?

    Also known simply as a hernia, a diaphragmatic hernia (DH) is a defect or tear in the diaphragm, which in turn allows the abdominal contents such as the liver or intestines to enter the chest cavity. This may either be a congenital abnormality (present at birth), or the result of trauma, such as that in a car accident or fall from a high building. When this happens, pressure is applied to the lungs, which causes difficulty breathing.

    The diaphragm (also known as  ‘thoracic diaphragm‘) is a sheet of muscle that separates the chest cavity (containing the heart and lungs) from the abdominal cavity (containing liver, gallbladder, stomach, kidneys, small intestine, large intestine, pancreas). It contracts and expands to draw air into, and out of the lungs.


    Mild or small hernias or only be associated with increased activity, which is known as the chronic form.

    • Dyspnea (shortness of breath)
    • Tachypnea (increased respiration)
    • Exercise intolerance
    • Lethargy
    • Muffled heart and lung sounds

    Other symptoms may also be present, depending on which organs have become trapped inside the chest cavity, which may include:

    • Gastrointestinal disturbances such as vomiting or diarrhea
    • Anorexia
    • Weakness
    • Coughing
    • Irregular heartbeat
    • Bloating due to damage to the stomach or intestines
    • Air in the chest cavity (pneumothorax)
    • Blood in the chest cavity (hemothorax)


    Your veterinarian will perform a complete physical examination of your cat and obtain a medical history from you. He will suspect a diaphragmatic hernia if the cat has had a recent car accident or fall. The abdominal cavity may feel empty upon palpitation.

    Diagnostic workup

    Abdominal and chest radiographs will reveal organs in the chest and a loss of the diaphragmatic line.


    If the cat has had a recent trauma, then it must be stabilised before treatment can commence. This may include:

    • Treat shock, blood transfusion (where necessary), oxygen therapy and fluids
    • Manage concurrent injuries, such as surgery to repair broken bones or lacerations
    • Thoracentesis (removal of fluid from the space between the lungs and the chest cavity, known as the pleura)

    Once the cat is stable, the diaphragm will need to be surgically repaired, this procedure is known as a herniorrhaphy.


    • Julia Wilson, 'Cat World' Founder

      Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio