Splenectomy

Splenectomy is the surgical removal of the spleen. This can be partial or total, however a partial splenectomy is rarely performed due to an increased risk of complications compared to a total splenectomy ¹.

Indications

Indications for a splenectomy can be divided into absolute and relative ².

Absolute indications

• splenic rupture: spontaneous rupture or high-grade traumatic rupture

  • the spleen is the most commonly injured organ in blunt abdominal trauma

• splenic artery aneurysm/pseudoaneurysm rupture: if unable to achieve hemostasis from embolization or ligation

• splenic abscess: e.g. from tuberculosis

• malignancy

  • local invasion from adjacent tumor, typically gastric carcinoma or pancreatic carcinoma

  • primary angiosarcoma: rare

Relative indications

• hypersplenism

• splenomegaly: if symptomatic

• splenic cysts: if symptomatic

• hemolytic anemia: e.g. hereditary spherocytosis, autoimmune hemolytic anemia

• other hematological disorders: e.g. immune thrombocytopenia, thalassemia, sickle cell disease

• hydatid infection

Notably, there is no indication for a splenectomy in cases of splenomegaly due to a lymphoproliferative disease (i.e. lymphoma) or congestive etiology such as portal hypertension ².

Procedure

CT can be performed pre-procedure for evaluation of splenic injury, to measure splenic volume, and identify accessory spleens (splenunculi). CT angiography is also useful for characterization of vascular anatomy including any variants ³.

A splenectomy is typically performed laparoscopically in the right lateral decubitus position, however open surgery may be performed in the case of trauma. The surgeon first enters the lesser sac via dissection of the gastrosplenic ligament, ligates the splenic vessels at the hilum using staples, then removes the spleen. In the case of an underlying disease, any accessory spleens are also located and removed ⁴.

Complications

The spleen is responsible for important hematological and immunological processes including the production of antibodies, removal of damaged blood cells, and destruction of encapsulated pathogens. Impaired immunity is therefore the major long-term concern following a splenectomy, particularly the risk of overwhelming post-splenectomy infection (OPSI).

Overwhelming post-splenectomy infection (OPSI) is a high mortality fulminant process (typically secondary to Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis) that can rapidly progress to coma and death within 24 to 48 hours ⁵. Splenectomy patients are therefore given pneumococcal, meningococcal, and influenza vaccinations pre-procedure. Immunosuppressed patients are further given life-long prophylactic antibiotics ².

Other complications are listed below ².

Acute complications

• hemorrhage

• subphrenic abscess

• thrombocytosis and leukocytosis: greater risk in splenectomy following trauma compared to elective splenectomy ⁶

• pancreatitis

Chronic complications

• overwhelming post-splenectomy infection (OPSI)

• disseminated intravascular coagulation (DIC)

• thromboembolism: including portal venous thrombosis, deep vein thrombosis, and pulmonary embolism

• increased risk of pneumonia and ischemic heart disease

• adhesive small bowel obstruction

Seeding of the peritoneal or thoracic cavity with splenic tissue may also result in splenosis, however this is largely a benign process.

Outcomes

Morbidity and mortality is higher in splenectomy patients than in the general population. However, patients who undergo a splenectomy following trauma have a better prognosis than those who undergo a splenectomy for an underlying disease process, suggesting that the long-term risks are associated with the underlying indication rather than from the splenectomy alone ².

History and etymology

The first documented splenectomy was performed by K S Quittenbaum in 1826 ². The spleen was long considered a redundant organ until 1952, when the risk of overwhelming post-splenectomy infection (OPSI) was highlighted by H King and H B Schumacher ². Since then, less invasive procedures such as splenic artery embolization have been advocated as a first-line treatment.

Differential diagnosis

For imaging appearances of an absent spleen consider:

• asplenia

• hyposplenism

• wandering spleen

• splenosis

• autosplenectomy: particularly in patients with sickle cell disease