In many instances, a dog can function perfectly well without its spleen. The reason for this is that the liver will take on most of the duties of the spleen, allowing the dog to get on with its life. However, if a dog's spleen is removed because it has a cancerous tumour growing, then the dog may need chemotherapy. If the cancer has spread, the dog may then die from the disease.
The spleen is a large lymphatic organ that acts as a filter that cleans a dog's blood by eliminating and destroying old red blood cells. It has a large blood supply and is attached to the dog's stomach by small, splenic arteries and veins, as well as by the gastrosplenic ligament. The spleen is divided into lobules lined with red pulp -- made up of tiny blood vessels -- and white pulp, which is made up of lymphocytes. The spleen has a close association with the dog's cardiovascular system.
Reasons for Removal
Dogs may develop both malignant or benign tumours of the spleen and this is one of the main reasons for a splenectomy. Of the malignant tumours, a large portion of them are hemangiosarcomas. This type of tumour often leads to the spleen rupturing and the dog is in danger of going into shock from the internal hemorrhaging. The prognosis with this type of cancer is poor because by the time the diagnosis is made, the cancer has most likely spread to other vital organs. Golden retrievers and German shepherds are the breeds most likely to have splenic tumours, which are more common in older dogs. In the cases of trauma, if the dog is hit by a car, the spleen can rupture and must be removed to stop the hemorrhaging.
Splenic torsion is an extremely painful condition that can occur in dogs. The spleen twists in such a way that the vein that drains blood away from the spleen becomes blocked, while the artery that supplies blood remains open. The result is that blood continues to flow into the spleen and then becomes overfilled with blood. Blood clots then form in the blood vessels and the spleen becomes necrotic. In this case, it must be removed.
After a splenectomy has been performed on a dog, its heart rate and blood pressure are monitored. Some dogs who have their spleens removed may develop abnormal heart beats. These arrhythmias can be dangerous and are potentially lethal. Medication may be needed to keep the dog's heart beating normally. Other complications that can arise after a dog's spleen has been removed include abnormal clotting, which can be fatal, and internal bleeding. The spleen is responsible for removing parasites from the blood and some dogs can develop hemobartonella infection after a splenectomy, which is a parasitic blood infection.