Spontaneous Pneumothorax and Lung Bullae
A spontaneous pneumothorax occurs when air enters and accumulates within the chest cavity without an obvious history of trauma. The trapped air prevents the lungs from expanding normally and can lead to partial or complete lung collapse.
This is a potentially life-threatening emergency requiring immediate veterinary treatment.
Lung Bullae
A spontaneous pneumothorax is often associated with compromised lung tissue or the formation of bullae near the edges of the lung lobes.
Bullae are thin-walled, air-filled spaces within or on the surface of the lung. They can look rather like bubbles in bubble wrap. If one ruptures, air leaks from the lung and accumulates within the chest cavity.
Other Possible Causes
Other conditions that may be associated with spontaneous pneumothorax in dogs include:
- Cancer
- Bacterial pneumonia
- A pulmonary abscess
- Fungal infection
- Heartworm disease
- Pulmonary thromboembolism
- Migration of a grass awn or another foreign body
Spontaneous pneumothorax is reported more frequently in large, deep-chested dogs, although it can potentially affect other dogs.
Signs Requiring Emergency Treatment
Possible symptoms include:
- Rapid or increasingly laboured breathing
- Breathing with obvious abdominal effort
- Coughing
- Restlessness or distress
- Stretching the neck forward to breathe
- An unusually expanded or overinflated chest
- Pale, grey or blue-tinged gums
- Weakness or collapse
Do not wait to see whether breathing difficulties improve. Keep the dog as calm and still as possible and contact a veterinary practice immediately.
Emergency Treatment and Diagnosis
The immediate priority is to stabilise the dog and restore adequate breathing and oxygenation. Oxygen may be administered and excess air may need to be removed from the chest.
A thoracostomy tube, commonly called a chest drain, may be placed through the skin into the chest cavity. This allows intermittent or continuous removal of air and gives the lungs an opportunity to expand more normally.
Once the patient is sufficiently stable, diagnostic imaging will normally be required. A CT scan can help identify bullae, diseased lung tissue or another possible source of the air leak.
Surgical Treatment
If the air leakage cannot be controlled medically or continues to recur, surgery may be required to identify and remove the affected lung tissue.
When ruptured bullae are responsible, treatment may include removing the affected lung lobe in a procedure known as a lung lobectomy.
Possible surgical approaches include:
- Thoracoscopy: a minimally invasive approach using small incisions and a camera
- Median sternotomy: entering the chest through the sternum
- Lateral thoracotomy: entering the chest between the ribs
The most appropriate approach depends upon the suspected cause and the location of the affected lung tissue.
Outlook and Recurrence
Many dogs undergoing surgery for pneumothorax associated with bullae have a successful outcome. However, recurrence is possible if another bulla develops or previously undetected abnormal lung tissue later ruptures.
If breathing difficulties return at any point, urgent reassessment and further imaging may be required.
Recovery Following Surgery
Recovery instructions depend upon the operation, the dog’s condition and the advice of the surgical team. Owners should always follow the individual discharge plan provided by their veterinary hospital.
Restrictions may include:
- Resting in a small, safe room or suitably sized pen
- Short, controlled lead walks for toileting
- No running, jumping or rough play
- No unnecessary stair climbing
- Preventing interaction that could cause overexcitement
- Regular checks of the surgical wound
- Attending all postoperative appointments
Exercise should be increased only in accordance with advice from the veterinary surgeon. Contact the practice promptly if the wound becomes red, swollen, hot, painful or begins to discharge, or if the dog’s breathing changes.
My Personal Experience
My own bitch was nine years old when she seemed off colour one morning and was not interested in her breakfast, which was very unusual for her.
She had been in season during the previous two months but had subsequently developed a pyometra and been spayed. Despite seeming a little unwell, she wanted to go out with the other dogs, completed her normal run and even chased the chickens.
I could not initially identify what was wrong, so I watched her closely. A few hours later, she coughed several times and I wondered whether she had kennel cough.
Her breathing then became laboured. Her abdomen dropped with each breath and, when she lay down, she stretched her neck forward. Her chest also felt unusually hard and expanded. My initial concern was bloat, so I telephoned the veterinary practice and told them I was on my way.
The veterinary team immediately recognised that her chest was full of air. She was placed on oxygen and I was told that a chest drain had to be inserted urgently to prevent her lungs from collapsing.
The following day, she was transferred to a referral hospital. A CT scan confirmed bullae, another chest drain was inserted and she underwent surgery the next day. This was followed by five days in intensive care.
The photograph below shows her surgical wound six days after the operation.
Keeping her rested and taking her outside only on a lead was challenging. Thankfully, she did not interfere with her main surgical wound, although she nibbled the smaller wounds where the chest drains had been inserted. These then required dressing changes at the veterinary practice every 48 hours.
Twelve weeks after the operation, she was allowed outside with the other dogs while remaining on a lead. Four months later, she was back to normal and nobody would have known what she had been through.
Julie Growcott
This page includes general information and personal experience. Breathing difficulties are always an emergency. Seek immediate veterinary attention rather than attempting to diagnose or treat the condition at home.