A splenectomy is the total removal of the spleen from the dog's body. The spleen is responsible for storing blood vessels and cleaning toxins from the blood. If damaged, it can bleed profusely into the abdominal cavity, causing anaemia, low blood pressure, shock and even death. Removal of the spleen is generally only performed if methods of repair are not sufficient.

The vet will begin by placing the dog under general anesthesia and shaving a large area along the abdomen. This is because a ruptured spleen will typically require an 'open splenectomy' in order to fully remove it. Next, they will make an incision along the abdomen and move aside any intervening tissues. Next, they will cut out and remove the spleen along with any associated fragments before sealing off the associated blood vessels. The final step is to clean up any possibly infected fluid and suture the incision shut. At this point, the dog can be allowed to recover from anesthesia.

Damage to the spleen is typically accompanied by other injuries (often serious), so it can be difficult to judge the effectiveness of the treatment by observing changes in the dog's behavior. However, the immediate danger posed by the ruptured, cancerous, or infected spleen will have been eliminated as soon as the surgeon extracts it from the body. While the effects of a splenectomy are permanent, owners should know that removal of the spleen will not have a major impact on their dog's quality of life, as its functions are shared by several other parts of the body. 

Following surgery, it can take over a month for the incision to fully heal. Because of this, the vet will provide owners with painkillers that can be administered to the dog at home. It will also be necessary for the dog to be fitted with an E-collar to prevent them from pulling out the stitches holding their abdomen closed. Additionally, due to the size of an open splenectomy incision, owners will have to dramatically reduce the amount of exercise their dog undertakes, as well as keeping a careful eye on them throughout the day. Additionally, antibiotic medication may be prescribed in order to prevent the dog from picking up an infection following the surgery (especially if the spleen itself was suffering from an infection).

The price of a splenectomy can be quite high. This is because of the diagnostic tests required in order to identify the problem in the first place, as well as the surgical knowledge required in order to perform the procedure. In all, most owners can expect to pay around $2,500 for a splenectomy. For older dogs or ones suffering from more complex conditions, the prices for the procedure can go even higher.

While the splenectomy can be a lifesaving procedure for many dogs, there are some attendant risks that may cause some owners to think twice. As with all major surgeries, the dog must be placed under general anesthetic, which can cause cardiovascular failure in some dogs. Additionally, without a spleen, there is an increased susceptibility to infection and longer recovery times from illnesses can be expected. For elderly dogs, these problems may be even greater, giving their owners pause for thought.

Although many cancers and infections are unpredictable and somewhat hard to guard against, owners can do a lot to mitigate the risk of direct injury to their dog's spleen. Due to the spleen's location high on the left flank of the dog, most injuries occur not through accidents in play caused by objects on the ground (unlike, for example, stomach injuries), but by being hit by cars and direct confrontations with other animals. By properly training their pet on how to act around roads and when encountering strange dogs, owners can reduce much of the risk of injury to the spleen.