Lung Lobe Twisting in Dogs

Lung Lobe Torsion in Dogs

Torsion, or twisting, of the lung lobe results in the obstruction of the dog’s bronchus and vessels, including the veins and arteries. The obstruction of the blood vessels causes the lung lobe to engorge with blood, which results in necrosis and death of the affected lung tissue. This may lead to many complications, including coughing up blood, tachycardia, or shock.

Male dogs are at a higher risk of lung lobe torsion than females, as are large, deep-chested. However, small dogs such as pugs (especially those younger than four) are also at risk, most often with the spontaneous form of lung lobe torsion.

Symptoms and Types

• Pain
• Fever
• Lethargy
• Loss of appetite (anorexia)
• Coughing (sometimes with blood)
• Difficulty breathing, especially while lying flat (orthopenea)
• Increased respiration rate
• Coughing up blood
• Increased heart rate
• Pale or bluish mucous membranes (cyanosis)
• Shock

Causes

Lung lobe torsion is inconsistently found with pre-existing conditions such as trauma, neoplasia, and chylothorax. However it also occurs spontaneously, due to a thoracic or diaphragmatic surgery, or, on occasion, due to an unknown cause (idiopathic).

Diagnosis

You will need to give a thorough history of your dog’s health, including the onset and nature of the symptoms, to your veterinarian. He or she will then perform a complete physical examination as well as a biochemistry profile, urinalysis, and complete blood count (CBC). These tests may reveal valuable information for initial diagnosis and may show signs of infection, anemia. It will also reveal the level of immune response of your dog. If the number of white blood cells is abnormally lower than the minimum normal range, the prognosis is very poor.

Your dog’s veterinarian may decide to take a small sample of the accumulated fluid for further evaluation, while ultrasound, computed tomography, and radiographic studies often reveal more details about the problem. Loss of normal architecture and blood vessels, along with opacification of the affected lung are usually seen in an X-ray.

In some cases, surgery is required for definitive diagnosis and treatment.