During the development of a fetus (unborn infant still in the uterus), the spleen is one of the sites of formation of blood cells. This function is taken over by the bone marrow by the fifth month of pregnancy. The spleen, however, still has the ability to produce blood cells in the adult under certain conditions.

Anatomy and Physiology

• The spleen lies in the left upper part of the abdomen. It is about 6 by 3 inches (15 by 7.5 cm.) in size and weighs 3 to 6 oz. (90 to 180 gm) (Figure 1)
• The spleen lies beneath the left lower ribs and is attached by ligaments to the left kidney, colon, stomach and undersurface of the diaphragm. It may be injured by trauma that fractures the overlying ribs
• The spleen acts as a filter that removes old, abnormal or damaged blood cells and bacteria from the blood. It also has a role in immunity by creating antibodies to help battle infection
• The spleen is a source of antibodies and is important in the immune system of the body for fighting disease

Figure 1 - The spleen lies just to the left of the stomach and just below the diaphragm. Blood to the spleen goes through the splenic and short gastric arteries and drained by the splenic vein (not shown).

Pathology and Indications for Surgery

Although not completely essential for life, removal of the spleen has been associated with increased risk of life threatening infections. Thus there is a trend towards preserving either whole or part of the spleen, particularly following trauma. The commonest indications for removal of a spleen are traumatic injury, idiopathic thrombocytopenic purpura and Hypersplenism.

• Trauma: The spleen is the commonest organ injured in blunt trauma to the abdomen. Injury to the spleen is also possible during an operation in the upper abdomen, (e.g. during stomach, kidney or esophagus surgery). As mentioned before, an attempt to save the spleen is usually made. The spleen is completely removed only in cases where the spleen is shattered or there is an injury to the main blood vessels of the spleen
• Autoimmune Disorders: In these diseases, the spleen produces abnormal antibodies that attack and destroy normal blood cells in the body. This may result in anemia, jaundice or abnormal bleeding. Surgery is once again indicated in case medical therapy, usually steroids, is not able to control symptoms:
  • Immune (Idiopathic) Thrombocytopenic Purpura (ITP). Antiplatelet antibodies that cause the destruction of platelets cause this disease
    1. The acute form of ITP occurs primarily in children after a viral infection
    2. The chronic form occurs primarily in adults
    3. Patients present with bleeding from various places such as easy skin bruising, bleeding from the gums, bloody nose, heaving menstrual bleeding, and occasionally bowel and urinary bleeding
    4. There are markedly decreased platelets on examination of the blood usually along with a normal bone marrow examination. Antibodies to platelets can usually be detected
    5. Treatment is usually not necessary if the platelet count is over 50,000 per milliliter and there are no or minimal symptoms
       • Platelet transfusion may be necessary when bleeding needs to be stopped immediately
       • Cortisone is given after the diagnosis is made for about two weeks. The steroids are reduced slowly when the white blood cell count exceeds 50,000
       • Splenectomy is the main treatment for ITP when the response to cortisone is not good
  • Autoimmune Hemolytic Anemia. Red blood cells coated with antibodies are caught in the spleen
    1. May be seen associated with leukemia, lymphoma or collagen vascular disease though most cases do not have a specific cause
    2. Primary treatment is cortisone
    3. If steroids fail then splenectomy may be necessary
• Blood Cell Disorders: In these disorders, there is excessive destruction of blood cells by the spleen due to either an inherited abnormal structure of the blood cells, abnormal molecules within the blood cells or abnormal damage to blood cells. Splenectomy may be indicated if there is failure of medical management or if the disease is severe, requiring frequent transfusions
  • Hereditary Spherocytosis or Hereditary Elliptocytosis. These are two diseases in which there is a hereditary abnormality of the shape of the red blood cells. The abnormal cells get caught in the circulation of the spleen resulting in destruction of the cells and anemia (low number of red cells in the blood
    1. The patient may have jaundice (yellow coloration of the skin), gallstones and an enlarged spleen
    2. Laboratory tests shows an increase of bilirubin in the blood (a breakdown product of red cells that results in yellowish discoloration), round or oval red blood cells and a low blood hemoglobin (the iron containing protein in red blood cells that give the cells their red color)
    3. Removal of the spleen prevents the breakdown of red blood cells and corrects the anemia. In Hereditary Spherocytosis, splenectomy is indicated in almost all patients and cholecystectomy is performed if gallstones are present. In Hereditary Elliptocytosis, most patients are without symptomatic anemia, but when there are symptoms splenectomy corrects the anemia
  • Thalassemia. This is a hereditary anemia caused by a defect in the formation of hemoglobin
    1. This results in severe anemia, enlargement of the liver and spleen and gallstones
    2. Initial treatment frequently includes the intravenous injection of an iron chelating agent, a chemical that binds free iron in the blood so that the body can get rid of the iron
    3. In severe cases, removal of the spleen removes the primary site causing red cell breakdown, thus reducing the number of blood transfusions needed to correct the anemia and also gets rid of the discomfort caused by a very large spleen
  • Thrombotic Thrombocytopenic Purpura (TTP). TTP is fairly rare and caused by damage to the cells lining blood vessels (thrombotic, blood clot forming; thrombocytopenic, decrease platelets; purpura, purple patches in the skin due to little hemorrhages)
    1. This results in widespread small clots developing in the smaller blood vessels. As a result there is a decrease in platelets (small blood cells that are involved In blood clotting), hemolytic (red blood cell breakdown) anemia, fever and kidney and nervous system damage
    2. TTP is a medical emergency that has to be rapidly treated
    3. Treatment is primarily replacing the blood plasma (blood without the red cells) using fresh frozen plasma from the blood bank over approximately a 1-2 week period. Cortisone and aspirin are usually added to the treatment
    4. Splenectomy has been used when the response to plasma exchange has been inadequate
• Myeloproliferative Disorders: These comprise a variety of conditions where the spleen, and liver produce blood cells just like the bone marrow, a function that stopped as a fetus. These blood cells may be abnormal and may cause pain due an enlarged liver or spleen, abnormal bleeding or blood clotting and jaundice. The spleen is removed to help relieve symptoms
• Tumors: The spleen may be involved in lymphoma or leukemias. While the spleen used to be removed in the past for diagnosis or to determine extent of the cancer, it is now treated with chemotherapy (drugs) or radiotherapy (X-ray). It is removed only if the patient develops hypersplenism. Other tumors of the spleen, although rare, may need splenectomy as treatment
• Hypersplenism associated with other conditions: Hypersplenism is a condition where the spleen undergoes a marked increase in normal spleen function
  • This may cause a painful increase in size of the spleen
  • There may be an abnormal destruction of blood cells
  • Hypersplenism may be a complication of several other diseases that may require splenectomy:
    1. Portal hypertension in which there is obstruction of the veins of the liver and spleen usually associated with alcoholic disease of the liver or pancreas that may cause painful enlargement of the spleen or bleeding into the stomach. The diagnosis is usually made by ultrasound, and treatment is usually splenectomy
    2. Leukemia
    3. Inflammation conditions of the spleen such as
    • Felty's syndrome (associated with rheumatoid arthritis)
    • Gaucher's disease (associated with abnormal metabolism of sugar)
• Miscellaneous conditions:
  • Splenic artery aneurysm and splenic cysts - some patients may be born with an abnormal dilation of the splenic artery or they may have abnormal fluid collections within the spleen. Splenectomy may be indicated if the aneurysm ruptures (usually in pregnancy) or if the cysts are large or cause symptoms
  • Splenic abscesses - The spleen may be a site of a pus filled collection due to an infection in the spleen or from infected debris elsewhere in the body (usually the heart or kidneys). The spleen may need to be removed to get rid of the infection

Diagnosis

• Patients may present with a variety of symptoms depending on the disease that is present.
• The spleen can usually not be felt on examination even when enlarged
• The enlarged spleen may cause pain in the left upper abdomen
• Excessive destruction of blood cells may leave one anemic with excessive tiredness or weakness or may cause jaundice
• There may be abnormal bleeding with spontaneous patchy bruises over the body called purpura or petechiae, or excessive bleeding from a minor injury
• Patients may have an increased incidence of infections particularly of the skin or lungs
• Blood clots may develop in the vessels of the arms and legs
• Blood tests may confirm the destruction of red blood cells (anemia), platelets (abnormal bleeding) or white blood cells (increased infection) · Laboratory tests may also detect abnormal antibodies in autoimmune disorders like ITP
• Abnormal looking cells may be seen in some of the blood cell disorders like thalassemia and spherocytosis
• Ultrasound may show the size of the spleen and evidence of blood around the spleen after injury
• Diagnostic Peritoneal Lavage in which a small incision in the abdomen. Sterile saline is injected into the peritoneum (the sac that contains the stomach and bowel) and then drained. If the drained saline contains blood, this is proof of bleeding inside the abdomen
• Computerized Tomography Scan. The spleen is easily seen on CT scan and can demonstrate spleen size, injury to the spleen, tumors, cysts or pus cavities within the spleen (Figure 2A and 2B)
• Arteriography. A catheter is inserted into the splenic artery and an x-ray is taken after a dye is injected. This may demonstrate an obstruction to blood flow to the spleen or a splenic artery aneurysm

Figure 2A - CT scans of the abdomen of two patients with splenomegaly (enlarged spleen). Patient showing moderate enlargement of the spleen. Courtesy S. Sadiq, MD	Figure 2B - Patient with a huge spleen. Courtesy S. Sadiq, MD

Surgical Procedures

• Preoperative preparation
  • Blood should be available for transfusion during surgery as the spleen has an extensive blood supply and may bleed considerably during the procedure
  • Platelets may be needed either before or during the operation in cases of ITP. Platelets are usually transfused after the splenic artery is clamped to prevent the platelets from being removed by the spleen
  • Steroids such as cortisone may be necessary
  • Polyvalent pneumoccocal vaccine should be given 2-3 weeks before surgery to all patients over 2 years of age due to the increased incidence of infections after the procedure, In cases of emergency splenectomy for trauma, vaccination should be given as soon as possible
  • In cases in which there is a very large spleen sometimes a catheter is placed into the splenic artery before surgery and material injected to block the artery. This can shrink the spleen and significantly reduce bleeding at the time of surgery
• General anesthesia is usually used
• Open splenectomy
  • An incision is made either below the lowest rib on the left side or an up and down incision is made in the middle of the upper abdomen
  • In non-emergency cases the splenic artery, which runs along the upper border of the pancreas, is sometimes located and tied off first. This loss of blood flow to the spleen makes it shrink and bleed less making the operation easier in patients with large spleens or hypersplenism (Figure 3A)
  • The ligaments that attach the spleen to surrounding structures are divided bringing the spleen forward and towards the midline. Care must be taken in dividing the ligaments between the stomach and the spleen since several small blood vessels may run through these ligaments
  • The main artery and vein are then are tied off and divided. Care must be taken at this point also to avoid injury to the pancreas, as the tail of the pancreas is close by (Figure 3B)
  • In cases of abnormal splenic function, the surgeon also takes care to look for accessory or extra spleens, which may be found in up to 20% of the population These must be removed or the disease process may recur
  • Before closing the wound with sutures, drains may be placed in this area of the removed spleen, especially in cases of surgery near the tail of the pancreas
  • A tube is placed into the stomach through the nose to keep the stomach drained for a few days

Figure 3A - Splenectomy - First the splenic artery is clamped and tied off with suture. Blood within the spleen drains into the splenic vein thus reducing its size. © N. Gordon	Figure 3B - The short gastric arteries are then tied off followed by the splenic vein. The spleen is then removed. © N. Gordon

• Laparoscopic Splenectomy
  • A laparoscope is a tube that contains fiber optics with a lens at one end and a television camera at the other
  • This surgery may take an hour or two longer than the regular method, but patients have shown to have a shorter hospital stay after the operation
  • The indications for this operation are the same as the open method; however, it should not be used with an extremely large spleen or if there is bleeding from the spleen
  • Laparoscopic splenectomy is usually done under general anesthesia
  • The patient is placed on the right side with his/her left side up, or flat on the operating table with the legs spread apart
  • Four to five small incisions (approx 1 cm. in size) are made on the abdomen for the introduction of the laparoscope and several long, thin instruments
  • Similar to the regular technique, the ligaments holding the spleen in place are divided, and then the main blood vessels are stapled across and divided. The spleen is usually placed in a bag and then broken into fragments while in the bag to allow it to be removed through one of the small incisions

Complications

• Complication related to anesthesia
• Respiratory complications
  • Atelectasis - The operation may cause pain on deep breathing so that a patients may fail to take adequate deep breaths causing collapse of small segments of the lungs, called atelectasis
  • This may give rise to fever and can progress to pneumonia
• Injury to surrounding structures - The spleen lies adjacent to several organs that may be injured in the course of the surgery such as the pancreas, stomach, colon and diaphragm
• Infection
  • Subphrenic abscess - Infection in the bed of the removed spleen may lead to a pus filled cavity under the diaphragm. This abscess cavity may be diagnosed and sometimes drained via a CT scan. In some cases drainage may require re-operation
  • Overwhelming PostSplenectomy Sepsis (OPSS)
    1. This is probably the most feared complication after a splenectomy. The increased risk of infection after a splenectomy gives rise to this syndrome where the patient may have over a 50% chance of dying
    2. A patient, who may have been previously healthy, usually suffers a respiratory infection that may progress within hours to shock, coma and death
    3. Specific bacteria usually cause the infections, and therefore, it is usually mandatory to give patients vaccinations to these bacteria before the operation. In emergency situations like trauma, the vaccinations should be given as soon as possible after the operation
  • Peritonitis (infectious or non-infectious inflammation of the lining of the abdomen)
  • Wound infection
• Bleeding
• Thrombocytosis - a marked increase in platelets leading to increased clotting in blood vessels
• Pancreatitis as a result of injury to the pancreas. This may lead to a fistula (tract) from the pancreas through the skin
• Injury to the stomach that may lead to a hole in the stomach wall
• Deep vein thrombosis (clots in the veins if the pelvis of legs) that may lead to pulmonary embolus (clot going to the lung)
• Death

Post-operative care

• Depending on the severity of the surgery, the patient may be sent to a regular surgical room or may be sent to the surgical intensive care unit to be more closely monitored
• The nasogastric tube is left in place and connected to suction to keep the stomach empty. The tube is removed when stomach and bowel function returns to normal, usually in 2 - 3 days
• Fluids are given by vein (intravenously, I.V.)
• Antibiotics are usually given I.V.
• Oxygen may be given by nasal catheter
• Deep breathing and coughing are stressed
• Patients are gotten up to sit and walk as they are able
• Gradually the diet is increased from liquids to soft food and then more solid foods
• The wound is kept clean to prevent infection
• The patient usually returns to the surgeon's office in one to two weeks after discharge
• Blood tests, CT scans and other diagnostic tests may be necessary to follow any problems
• Patients are usually discharged on the 3-4 day postoperatively. Patients are usually given instructions to take an antibiotic before minor surgeries, or as soon as they notice a mild fever. Although not proven to be necessary, their vaccination may need to be repeated every 10 years