Lung Lobe Torsion in Cats 

What is lung lobe torsion? 

Cats have several lung lobes, which function as separate sections of the lungs. Lung lobe torsion occurs when one of these lobes twists around itself. When this happens, the blood vessels and airway supplying that lobe become compressed and obstructed. 

At first, blood can still enter the affected lung lobe, but it cannot drain away properly. This causes congestion, swelling and fluid build-up. As the torsion continues, the tissue becomes damaged and may eventually start to die. The condition can also lead to fluid accumulating around the lungs inside the chest cavity, making breathing even more difficult. Lung lobe torsion is much more commonly reported in dogs than in cats, but feline cases do occur and can become life-threatening if not treated quickly. 

What causes lung lobe torsion in cats? 

Sometimes, lung lobe torsion appears to happen without any obvious underlying cause. This is known as idiopathic lung lobe torsion. In many cats, however, there is another disease process affecting the chest at the same time. Conditions linked with lung lobe torsion include: 

• Pleural effusion (fluid around the lungs) 

• Chylothorax (build-up of lymphatic fluid in the chest) 

• Chest trauma 

• Diaphragmatic hernia 

• Lung inflammation 

• Previous thoracic surgery 

• Lung tumours 

• Severe respiratory infections 

One of the theories is that excess fluid in the chest allows the lung lobes to move around more freely than normal, increasing the risk of twisting. Because lung lobe torsion is uncommon, there is still quite a lot we do not fully understand about why it develops in some cats and not others. 

Which cats are affected? 

There does not appear to be a strong breed predisposition in cats. Cases have been reported in both pedigree and domestic cats of various ages. Middle-aged and older cats seem to be diagnosed more often, although younger cats can still be affected. 

What signs might owners notice? 

The signs can vary a lot depending on how severe the torsion is and how long it has been present. Some cats become suddenly very unwell, while others develop more gradual symptoms over several days. 

Common signs include: 

• Fast breathing 

• Increased effort when breathing 

• Open-mouth breathing 

• Lethargy 

• Reduced appetite 

• Hiding away 

• Weakness 

• Weight loss 

• Pale or bluish gums 

• Coughing, although this is less common in cats than in dogs 

Some owners may just notice that their cat “isn’t right”. Cats are very good at hiding illness, particularly respiratory disease, so even subtle changes can be important. 

Any cat showing breathing difficulties should be treated as an emergency and seen by a vet as soon as possible. 

Why does fluid build up around the lungs? 

Many cats with lung lobe torsion develop pleural effusion, which means fluid collects in the space around the lungs rather than inside them. 

This fluid prevents the lungs from expanding normally and can significantly worsen breathing difficulties. The fluid may contain blood, inflammatory material or lymphatic fluid depending on the underlying cause and how long the torsion has been present. In some cases, removing this fluid with a procedure called thoracocentesis gives immediate relief and helps cats breathe more comfortably. However, it is important to understand that draining the fluid does not fix the torsion itself. 

How is lung lobe torsion diagnosed? 

Diagnosing lung lobe torsion can sometimes be tricky because the signs overlap with many other chest diseases. 

Physical examination 

Your vet will begin by performing a full physical exam. They will usually start by listening to your cat’s chest. Cats with pleural effusion often have muffled heart and lung sounds because the surrounding fluid dampens the normal noises. Many affected cats also breathe rapidly and may seem distressed or anxious due to a lack of oxygen. 

Chest X-rays 

Thoracic radiographs are usually the first imaging test performed. They may show: 

• Fluid around the lungs 

• An abnormal lung lobe 

• Areas of lung consolidation 

• Shifts in structures within the chest 

Unfortunately, X-rays alone cannot always confirm lung lobe torsion because several other diseases can look similar. 

Ultrasound 

Chest ultrasound is useful for identifying pleural effusion and guiding fluid drainage safely. It may also help assess abnormal lung tissue. 

CT scan 

Computed tomography (CT) is considered the best imaging test for diagnosing lung lobe torsion. A CT scan provides far more detail than standard X-rays and can often show the twisted lung lobe directly. CT imaging may reveal: 

• Twisting of the airway and blood vessels 

• Collapse or swelling of the affected lobe 

• Trapped gas within the lobe 

• Areas of dead tissue 

• Associated chest disease 

Referral centres increasingly rely on CT scanning because it improves the chances of making a diagnosis before surgery. 

What other conditions can look similar to lung lobe torsion? 

Several diseases can mimic lung lobe torsion, including: 

• Pneumonia 

• Lung tumours 

• Pyothorax 

• Feline infectious peritonitis (FIP) 

• Heart disease 

• Pulmonary abscesses 

• Bleeding into the chest cavity 

This is one reason why advanced imaging is often recommended. 

How is lung lobe torsion treated? 

Unfortunately, lung lobe torsion cannot be treated successfully with medication alone. The affected lung tissue is usually too damaged to recover. Surgery is therefore the treatment of choice. 

Stabilising the patient first 

Before surgery, many cats need emergency stabilisation. This may involve: 

• Oxygen therapy 

• Draining fluid from the chest 

• Pain relief 

• Intravenous fluids if appropriate 

• Careful monitoring 

Cats with breathing difficulties can deteriorate quickly if stressed, so vets usually try to handle them as gently and minimally as possible. 

Surgery for lung lobe torsion 

The operation performed is called a lung lobectomy, which means surgical removal of the affected lung lobe. Although the idea of removing part of the lung sounds dramatic, cats generally cope surprisingly well after losing a single lung lobe. During surgery, your vet will carefully seal off the blood vessels and airway supplying the damaged lobe before removing it. One important point is that the twisted lobe is not untwisted beforehand, as untwisting it can release harmful inflammatory substances and blood clots into the circulation. Once the twisted lobe is removed, the chest cavity is then checked carefully for any underlying disease or additional complications. A chest drain is often placed temporarily after surgery to remove residual air or fluid. 

What is the recovery like? 

Recovery varies depending on how sick the cat was beforehand and whether any other diseases are present. Some cats improve quite quickly after surgery once the diseased lung tissue has been removed. Others require intensive monitoring for several days. 

Potential complications can include: 

• Persistent pleural effusion 

• Infection 

• Breathing difficulties 

• Air leakage from the lungs 

• Heart rhythm disturbances 

Pain relief is a very important part of recovery. Thoracic surgery can be uncomfortable, and modern analgesia protocols make a big difference to patient comfort. Most cats remain hospitalised for several days following surgery. 

What is the prognosis for lung lobe torsion in cats? 

The prognosis for lung lobe torsion is variable. Cats that are diagnosed promptly and undergo successful surgery can go on to live very normal lives afterwards. Cats generally tolerate the removal of one lung lobe well. However, prognosis becomes more guarded if: 

• Diagnosis is delayed 

• There is severe respiratory compromise 

• Significant underlying disease is present 

• Multiple lung lobes are affected 

• Serious postoperative complications develop 

Published studies suggest that while many cats survive long-term, perioperative complications are relatively common. Cats with concurrent thoracic disease may have a poorer outcome overall. 

Can lung lobe torsion be prevented? 

There is no guaranteed way to prevent lung lobe torsion, particularly when it occurs spontaneously. Prompt investigation of breathing problems and pleural effusion may help identify underlying chest disease earlier, but some cases develop unpredictably despite good veterinary care. 

Owners should always seek veterinary attention straight away if they notice: 

• Fast or laboured breathing 

• Open-mouth breathing 

• Sudden lethargy 

• Collapse 

• Persistent hiding 

• Reduced appetite combined with breathing changes 

Cats often show respiratory disease quite subtly at first, so even mild changes can be significant. 

Why is early diagnosis so important? 

One of the biggest challenges with lung lobe torsion is that it is not usually the first condition vets suspect. Understandably, more common diseases such as pneumonia, heart disease or pleural effusion secondary to other causes are often considered first. Because cats can compensate for respiratory disease until they suddenly cannot cope any longer, delays in diagnosis can sometimes occur. 

The earlier the condition is recognised and treated surgically, the better the chances of a successful outcome. 

Final thoughts 

Lung lobe torsion in cats is rare, but it is a serious condition that requires veterinary attention. Many affected cats present with non-specific signs such as breathing difficulties, lethargy and reduced appetite, which can make diagnosis challenging initially. Advances in imaging, particularly CT scanning, are helping vets diagnose the condition more accurately than in the past. Surgical removal of the affected lung lobe remains the best treatment, and although the surgery is major, many cats recover well afterwards. 

For owners, the most important thing is recognising when a cat’s breathing is not normal. Cats are very good at disguising illness, and subtle respiratory changes should never be ignored.