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.
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.