Splenectomy

The usual indications for splenectomy are:

trauma — either following an accident or during a surgical operation, for example when mobilising the splenic flexure of the colon;

removal en bloc with the stomach as part of a radical gastrectomy;

removal as part of a staging laparotomy undertaken before treatment of a Hodgkin’s lymphoma, a very rare indi­cation with the advent of improved staging by imaging;

to reduce anaemia or thrombocytopenia in spherocytosis, ITP or hypersplenism;

in association with shunt or variceal surgery for portal hypertension.

  Other indications for splenectomy are given in Table 53.1.

Technique of splenectomy

Most surgeons use a left paramedian or transverse left subcostal incision. For a large spleen adherent to the diaphragm a thoracoabdominal incision may he necessary. Before operation, the passage of a nasogastric tube enables the stomach to be emptied. This eases the identification of the abdominal oesophagus and decompresses the stomach during the procedure; however, it should be removed at the end of the operation.

If the operation is for traumatic rupture, a quick mobilisation is necessary. The hand is passed round the outer surface of the spleen, the posterior layer of the lienorenal ligament divided largely by blunt dissection and the spleen rotated medially into the incision. A large pack is inserted behind the spleen and the short gastric vessels, and those in the pedicle are ligated and divided. It is important to separate the tail of the pancreas from the vessels in the hilum before ligation (see below, and the subsection on ‘Rupture of a malarial spleen’ above).

For other conditions requiring splenectomy, the first step is to open the gastrosplenic ligament and divide the short gastric vessels (Fig. 53.5). The splenic vessels at the superior border of the pancreas are underrun with Vicryl and ligated. The posterior surface of the spleen is exposed, the posterior leaf of the lienorenal ligament divided by long curved scissors and the spleen rotated medially, together with the tail and body of the pancreas. The pancreas is separated from the hilum and the vessels are dissected out, ligated and divided. A careful search must be made for accessory spleens. The wound should not be drained, as haemostasis must be perfect before closure of the abdomen.

Postoperative complications

       Haemorrhage, if a ligature slips off the splenic artery.

Gastric dilatation following partial mobilisation of the stomach when ligating the short gastric vessels.

       Haemetemesis may rarely occur — possibly due to mucosal damage to the stomach when ligating the short gastric vessels.

Left basal atelectasis, sometimes with pleural effusion, is common. This may be due to damage or to irritation of the left hemidiaphragm or a subphrenic abscess, and may he accompanied by persistent hiccough.

Damage to the tail of the pancreas during mobilisation of the splenic pedicle. This may produce a localised abscess or, if the area has been well drained, a pancreatic flstula. This may be associated with a left pleural effusion, a peritoneal effusion or abdominal wall dehiscence.

       Splenectomy is frequently followed by a rise in the white cell and platelet count a few days after operation. There may be a risk of thrombosis if the platelet count rises above 1000 x I 09/litre and it is essential to anticoagulate prophylactically the patient should this level be attained.

Gastric flstula due to damage of the greater curvature of the stomach when ligating the short gastric vessels.

       Postsplenectomy septicaemia. The spleen phagocytoses bacteria, particularly encapsulated bacteria. Splenectomised patients show reduced antibody production when challenged with particulate antigens, are deficient in tuftsin, and may have reduced 1gM and properdin levels (see the subsection on ‘Functions of the spleen’ at the start of this chapter). Splenectomised patients are at increased risk of septicaemia due to Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae and Babesia microti. The risk becomes ever greater in splenectomised patients treated with cytotoxic chemothera­py or radiation, and in patients who have undergone splenectomy for thalassaemia, sickle cell disease, and autoimmune anaemia or thrombocytopenia.

Opportunist postsplenectomy infection (OPSI) is now of major concern. Pneumococcal antitoxin (Pneumovax) should be given 2 weeks preoperatively. It is important to advise the patient of the dangers of OPSI and to prescribe antibiotics with all infections. As previously mentioned, splenectomised patients living in malaria endemic areas should receive antimalaria prophylaxis.

Because of concern over correct management of patients following splenectomy, guidelines have been produced by a working party of the British Committee for Standards in Haematology. They are set out in Table 53.2. It should be noted where the recommendation is based on published evidence and that of expert opinion. The authors note that there are no randomised controlled trials or case-controlled studies on this issue, which is why the level of evidence is poor and emphasises the difficulty in making recommendations in a subject where the incidence of opportunist infection is not known.