Hearing that your dog needs a thoracotomy is something that will make most owners feel extremely worried. The word itself sounds serious, and rightly so, as a thoracotomy is a major surgical procedure. It involves opening the chest so that your vet can directly access structures inside the thorax, including the lungs, oesophagus, heart, major blood vessels, and the tissues surrounding them. There are a number of different reasons why this type of operation may be recommended, and in some cases, surgery can be life-saving. The important thing for owners is understanding why your dog needs one and what exactly is involved.  

What is a thoracotomy? 

A thoracotomy is a surgical incision through the chest wall to allow your vet to reach the organs and tissues inside the chest. The approach used depends on what needs to be treated and where it is located. A lateral or intercostal thoracotomy accesses the chest through the space between the ribs. A median sternotomy involves dividing the sternum to provide access to the thoracic cavity. 

The choice of approach isn’t arbitrary. Your vet will select the incision that gives them the safest and most appropriate access to the area that needs treatment. For example, an intercostal thoracotomy may be used to perform a lung lobectomy, while a median sternotomy can provide access to a wider area of the chest. Although minimally invasive techniques such as thoracoscopy are increasingly available, an open thoracotomy remains necessary for some conditions and some patients. In other cases, minimally invasive surgery may be considered, but the surgeon may recommend an open procedure because it provides better access or visibility for the particular problem being treated. 

Why might a dog need a thoracotomy? 

Removing part of a lung 

A common reason for thoracic surgery is the need to remove an affected portion of lung. This procedure is called a lung lobectomy. Dogs have several lobes to each lung, and removing one diseased lobe does not mean that the remaining lungs stop working. If a lung lobe is severely damaged, diseased or no longer functioning normally, removing it allows the remaining healthy lung tissue to expand and function normally. A lobectomy may be recommended for conditions such as a lung tumour, a severely damaged or infected area of lung, a lung lobe torsion or certain traumatic injuries. 

Lung lobe torsion occurs when a lung lobe twists around its blood vessels and airway. The blood supply and drainage to the affected lobe become compromised, and the lobe can rapidly become severely damaged. The treatment is usually surgical removal of the affected lobe rather than attempting to untwist and preserve it. Fortunately, modern studies have shown that the outlook following surgery can be considerably better than many owners might expect. Your dog’s overall health, the severity of the disease and whether there are other problems present will all influence the outcome, but it is a useful reminder that the words “thoracotomy” and “lung surgery” shouldn’t automatically be interpreted as meaning that a dog has a poor chance of recovery, despite the fact it does sound scary.  

Cancer 

A mass within the chest is another reason why thoracic surgery may be recommended. 

Sometimes imaging such as radiographs or CT gives the veterinary team enough information to know that a mass is present, but surgery is needed to determine exactly what it is or to remove it. If a tumour is confined to a particular lung lobe, removing that lobe may be advised. In selected dogs, minimally invasive thoracoscopic surgery can sometimes be used for lung lobectomy, particularly when the size and location of the tumour make this appropriate. Open surgery remains an important option when thoracoscopy cannot provide sufficient access or visualisation. It is also important to understand that finding a mass does not automatically mean that surgery will cure the disease. Some tumours are more aggressive than others, and the presence of spread to other parts of the body can significantly affect treatment options and prognosis. This is why your vet may recommend further imaging, such as a CT scan, before deciding exactly what surgery is appropriate. 

Other structures in the chest cavity 

The chest contains much more than the lungs, so thoracotomy isn’t exclusively a “lung operation”. Surgery may be required to treat certain problems affecting the oesophagus, the tissues around the heart, the lymphatic system, or the mediastinum, which is the central area of the chest between the lungs. More common reasons include: 

Oesophageal foreign body 

An oesophageal foreign body may occasionally become stuck within the chest. Endoscopy is generally preferred when an oesophageal foreign body can be safely removed that way, because it is less invasive. However, surgery may become necessary when the object cannot be removed safely using minimally invasive techniques or when the oesophagus has perforated.  

Chylothorax 

Another example is chylothorax, where a type of lymphatic fluid called chyle accumulates within the chest. Persistent or idiopathic chylothorax can sometimes require surgery involving the thoracic duct, which is the major lymphatic vessel responsible for transporting lymph through the chest. Surgical treatment can be complex, and techniques have evolved over time. Thoracic duct ligation can be performed using minimally invasive techniques in suitable dogs, while open thoracotomy remains an option when appropriate.  

Pericardectomy 

Pericardectomy involves surgically removing part or, in some cases, most of the pericardium, the sac surrounding the heart. It may be performed in selected dogs with recurrent pericardial effusion or constrictive pericardial disease. Depending on the procedure and the individual patient, it may be performed through an open thoracotomy or using minimally invasive techniques. 

Why can’t my dog just have a keyhole operation? 

Thoracoscopy, sometimes referred to as keyhole surgery of the chest, has become increasingly useful in veterinary medicine. It involves placing a camera and surgical instruments through small incisions rather than opening the chest through a larger incision. 

Where it is suitable, this can offer advantages associated with minimally invasive surgery. However, thoracoscopy isn’t appropriate for every patient or every condition. The location and size of the problem, the amount of tissue that needs to be removed, the presence of adhesions or inflammation, and the surgeon’s ability to safely visualise and manipulate the affected structures all influence the decision. 

Sometimes a procedure planned as minimally invasive surgery also needs to be converted to an open thoracotomy because adequate access or visualisation cannot be achieved. This isn’t necessarily a complication or something that has “gone wrong”; it can be the safest decision for the patient. Your vet will be able to explain why an open approach is recommended in your dog’s particular case. 

What happens during a thoracotomy? 

Your dog will need a general anaesthetic, and thoracic surgery requires careful anaesthetic monitoring because the lungs and chest cavity are directly involved in the procedure. Once the chest has been opened, your vet can examine the affected area and perform the planned procedure. Depending on the reason for surgery, this could involve removing a lung lobe, removing a mass, repairing damaged tissue, removing a foreign body, or performing surgery on structures such as the thoracic duct. 

Because opening the chest temporarily interferes with the normal pressure relationships required for the lungs to inflate, dogs undergoing thoracic surgery require specialist anaesthetic management and assisted ventilation during the procedure. Careful monitoring of oxygenation, ventilation, and cardiovascular function is particularly important. A chest drain is also commonly placed at the end of surgery. This helps remove residual air or fluid and allows the lungs to re-expand appropriately. The drain can look alarming when you first see it, but it has an important job and is removed once the veterinary team is satisfied that it is no longer needed. 

Is a thoracotomy painful? 

A thoracotomy involves an incision through the chest wall, and the tissues between the ribs are manipulated during surgery, so it is a painful procedure. Thoracic surgery is recognised as being associated with significant postoperative pain, which is why good pain relief is such an important part of the anaesthetic and postoperative plan. Modern veterinary pain management is very advanced. Dogs undergoing thoracic surgery will receive a combination of different analgesic techniques and medications, tailored to the individual patient and the procedure being performed. Local anaesthetic techniques, systemic pain relief, and other components of multimodal analgesia can all be used. Effective pain control is particularly important after chest surgery because pain can interfere with normal breathing and coughing, which can then affect recovery. 

What are the risks associated with thoracotomy surgery? 

As with any major operation, thoracotomy carries risks. These include complications associated with the anaesthetic, bleeding, infection, problems involving the lungs, persistent air leakage, problems associated with the chest drain, and postoperative respiratory complications. The underlying disease also has a major influence on the risks involved.  

What will recovery be like? 

Your dog will usually remain in hospital following a thoracotomy so that their breathing, pain levels, oxygenation and chest drainage can be monitored closely. The length of hospitalisation varies considerably depending on the reason for surgery and how the individual patient recovers. Dogs with uncomplicated recoveries may be discharged relatively quickly, whereas dogs with ongoing fluid production, infection, or other complications may need considerably longer hospitalisation. 

At home, your dog will generally need a period of restricted activity. Your vet team will provide instructions about exercise, medication, wound care, and follow-up appointments. These instructions are important even if your dog seems comfortable. 

You should contact your vet promptly if your dog develops increasing breathing difficulty, marked lethargy, collapse, worsening pain, significant wound swelling or discharge, or anything else that concerns you after discharge. 

Final Thoughts 

It is entirely reasonable to be frightened when your dog is facing major surgery. Thoracotomy is performed because your vet believes there is something within the chest that needs to be accessed, removed or repaired, and that surgery offers an appropriate way of doing this. In some conditions, surgery can be genuinely life-saving. The best thing you can do is ask your vet to explain exactly what they have found, why surgery is recommended, whether minimally invasive alternatives are appropriate, what the main risks are and what they expect your dog’s recovery to look like, so you are able to make informed decisions about your dog’s care. A thoracotomy is a big operation, but veterinary surgical and anaesthetic techniques have advanced enormously in recent years. For many dogs, the aim is that once they have come through the surgery and recovered, they can return to enjoying a comfortable and good quality life again.