Surgery involving the chest is termed “thoracic surgery”.  A thoracic surgery may be performed for diseases of the heart, lungs, esophagus, mediastinum or ribs.  Thoracic surgery is done via a thoracotomy.  There are two thoracotomy approaches.  A median sternotomy is done by making an incision along the sternum (breastbone).  An intercostal thoracotomy is done by incising the muscles in between the ribs and then spreading them.  The problem that needs to be addressed dictates which approach will be made.

Heart diseases

There are a number of heart diseases that can be treated surgically.  There are hospitals that utilize cardiac bypass equipment to perform surgeries on parts of the heart that would otherwise be inaccessible, like the valves and the walls of the chambers.  These are very complex procedures and are only performed at a few locations around the United States.  At STVS, we perform cardiac surgeries that do not require cardiac bypass.

PDA

A vessel exists in the fetus that shunts blood away from the lungs, which a fetus does not use, and then closes down shortly after birth.  This vessel is called the ductus arteriosus.  If this vessel does not close, then it allows blood to flow through it.  This is called a patent ductus arteriosus, or PDA.  After birth, because of different pressures that iexist in the cardiovascular system, blood is either shunted to the lungs and away from normal circulation, or vice versa.  A PDA may be suspected based on a physical examination, where a heart murmur may be heard (or in some cases actually felt) when ascultating the chest.  Radiographs of the chest and an ultrasound of the heart can confirm the diagnosis and let us know if surgical treatment is advised.  If this heart defect is left untreated, animals will often go into heart failure by one year of age and die. 

            There are two ways this problem can be treated.  We perform surgery to gently free the abnormal vessel and then tie it off with non-absorbable suture.  This stops the flow through the vessel and causes blood flow to occur in a normal direction.  Other facilites may use a procedure called coiling, where a vascular occlusion coil is inserted into the PDA, where it helps form a clot that stops blood from flowing through the abnormal vessel.  The coil procedure has certain requirements to be used, and a cardiologist can determine if your pet may be a candidate for this.

            Surgery is usually a cure for this problem in young animals.  Often signs that heart disease is present may reverse after surgery is performed.  This may not happen in older dogs and in large breed dogs, but surgery still helps better treat the heart disease.

Pericardiectomy

            The pericardium is the covering of the heart.  A space exists between the heart and the pericardium.  Blood, fluid, or air may accumulate in this space because of cancer, infection, trauma, or unknown causes.  This can put pressure on the heart, because the pericardium is not able to stretch, and cause it to be unable to function.  Diseased pericardium can scar and can contract around the heart, and put pressure on the heart as it scars.  The pericardium can also develop cancer, or it can leak fluid.  For these problems, removal of a portion of the pericardium may be recommended to help decrease fluid buildup, reduce scar tissue constriction, or remove cancer.

Lung diseases

            Leakage of air from a damaged lung may occur because of trauma or diseases of the lungs that cause them to weaken.  Air leakage may resolve without an actual surgery.  Sometimes a procedure called thoracocentesis, where air is removed from the chest cavity with a needle and a syringe, may be sufficient.  A chest tube may need to be placed if air builds up on a continuous basis.  This can be emptied by a syringe, or contiuous suction may be applied to the tube with a vacuum device.  If these procedures do not resolve the problem, then surgery may be needed.

            Cysts and bullae may form on the lungs.  They are blister like, containing air, and if they rupture they cause air leakage.  Infection of an area of the lungs may cause an abscess to form which may not be medically treatable.  Lung lobes may twist along the airway and vessels that supply it, causing a lung lobe torsion.  Cancer may occur in all of or in a portion of a lung lobe.

            Any of these problems may necessitate removal of a part of or all of a lung lobe, or removal of more than one lung lobe.  Dogs can tolerate removal of over half of their total lung capacity without significant long term problems. 

Esophagus

            Surgery of the esophagus may be done for foreign objects that cannot be removed with an endoscope, trauma, diverticula (outpouchings), cancer and vascular ring anomalies.  Foreign bodies lodged in the esophagus as it travels through the chest require a thoracotomy to remove them.  Any trauma to the esophagus by penetrating chest wounds or by damage by something that the animal may have swallowed may need to be addressed surgically to prevent food and liquid from leaking from the esophagus into the chest.  Outpouchings of the esophagus called diverticula, can form from something inside the esophagus putting pressure on the wall, or from something outside the esophagus pulling it.  Food and fluid can pool in the outpouching, which causes obstruction, pain, regurgitation, and difficulty swallowing.  Cancer of the esophagus may need to be removed.  This can be very difficult because healing of the esophagus is not consistent, and strictures or scars can form.  Vascular ring anomalies are congenital defects of vessel formation.  The vessels coming from the heart form abnormally and put pressure on the esophagus so that food cannot travel past it.  The band that is constricting the esophagus is removed to allow for flow through the esophagus.  These animals may need medical treatment of some sort for the rest of their lifetime, but they can do well with good management and a diligent owner.

Other problems

Ribs.  Surgery of the ribs is most often performed for tumors that require their removal.  One or more may be removed and the chest wall may be reinforced with muscle or with a synthetic mesh material.  On occasion, rib fractures may need to be addressed surgically, but most rib fractures are treated conservatively and allowed to heal on their own over time.

Thoracic duct.  The thoracic duct carries a mixture of fats and blood cells called lymph from the lower half of the body back into the general circulation.  It travels through the abdomen and chest.  This vessel may become leaky for numerous reasons, and lymph escapes from its conduit and exudes into the chest cavity.  This is called a chylothorax.  If there is some underlying cause of chylothorax, it needs to be addressed.  In some cases, this problem may be treated with medications that increase the degredation of the lymph and by evacuating the chest fluid with a needle and syringe.  Often, surgery is required to address any underlying cause, to tie off the thoracic duct to prevent leakage, and to remove the covering of the heart (see pericardium section above).  Doing these procedures at the same time greatly increases the chance that surgery will be successful.

Neoplasia.  Other cancerous masses may occur in the chest cavity.  Some of these should be addressed with a surgery, like thymomas, a cancer of the thymus.  Others, like lymphoma, are better treated with chemotherapy or radiation therapy. 

Pyothorax.  Infection of the chest cavity will cause pus to accumulate in the space between the lungs and the chest wall.  This may be caused by penetrating healed chest wounds (including bite wounds), a migrating foreign body, perforation of the esophagus, or by repeated chest taps that could introduce bacteria.  Accumulation of fluid will cause animals to have difficulty breathing, fever, and general illness.  This problem is often treated medically by placing large chest tubes that are flushed once or twice daily with sterile fluid for several days to a week until the fluid is clear.  If this does not cause the infection to resolve, then surgery may be needed to explore the chest. 

No matter why thoracic surgery is being performed, this is a major surgery and recovery can be unpredictable.  Young puppies and kittens tend to recover quickly, and are often back to normal in a few days to a week.  Older animals may take considerably longer to recover.  Chest tubes are commonly placed after surgery to monitor the production of fluid or air.  Some patients require nasally delivered oxygen supplementation after surgery.  Patients often experience more discomfort from a thoracic surgery when compared to other types of surgeries.  At STVS, we are very aggressive with pain management for all of our patients, and especially after a thoracic surgery.  Patients may be hospitalized for several days or longer, dependent on how their recovery is progressing.