Liver
transplantation
Starzl first attempted liver transplantation in 1963, and by 1967 had
obtained prolonged survival. The first liver transplant performed outside the
USA was undertaken in Cambridge by Caine in 1968. Throughout the 1970s liver
transplantation remained a hazardous procedure that frequently failed, but the
introduction of a number of changes led to improved results. These included
improved immunosuppression, in the form of cyclosporin, together with improved
patient selection and refinements in organ preservation and attention to
technical aspects of the transplant operation. Liver transplantation is now a
routine operation in specialist centres.
Indications
and patient selection
The indications for liver transplantation fall into four groups:
• chronic cirrhosis;
• acute fulminant liver failure;
• metabolic liver disease;
• primary hepatic malignancy.
The
most common indication for transplantation is chronic liver failure. In adults
the causes include primary biliary cirrhosis, viral liver disease, alcoholic
liver disease and sclerosing cholangitis. In children, who account for around
10—15 per cent of all liver transplants, biliary atresia is the most common
indication for transplantation. Acute fulminant liver failure requiring
transplantation on an urgent basis accounts for approximately 10 per cent of
liver transplant activity and is viral or drug (e.g. paracetamol) induced. There
is a variety of metabolic diseases for which transplantation offers the prospect
of cure. These include Wilson’s disease, oxalosis and a1-antitrypsin
deficiency. Hepatic malignancy is only occasionally treated by liver
transplantation because of the high risk of tumour recurrence. Hepatomas, when
they occur in a cirrhotic liver, may be best treated by transplantation and some
centres consider transplantation for cholangiocarcinoma, although there is a
high risk of recurrent disease.
Technique
of liver transplantation
A transverse abdominal incision with a midline extension is made and the
diseased liver mobilised (Fig. 11.18). Because of portal hypertension the
recipient hepatectomy is often the most difficult part of the operation,
especially if there has been previous surgery in the region. The common bile
duct is divided, as are the right and left hepatic arteries. The inferior vena
cava is clamped and divided above and below the liver, and the portal vein is
clamped and divided allowing the recipient liver to be removed. Occlusion of the
vena cava and portal vein results in a reduction in cardiac output and may
necessitate the use of veno-venous bypass. The bypass circuit delivers blood
from the portal vein and inferior vena cava back to the heart via a cannula
inserted into the axillary vein or the internal jugular veins. After placing the
donor liver in position, the supra- and infrahepatic caval anastomoses are
performed The portal vein and the hepatic arterial anastomosis are then
completed and the graft is reperfused. Finally, biliary drainage is
re-established, usually by a duct-to-duct anastomosis (without the use of a
T-tube). It may be necessary, for example in recipients with biliary atresia or
sclerosing cholangitis, to reconstruct the biliary drainage by a bile duct to
Roux loop anastomosis. An alternative ‘piggyback’ technique of liver
transplantation is sometimes preferred in which the diseased native liver is
dissected from the intact inferior vena cava and the suprahepatic vena cava of
the donor is anastomosed end-to-side to the anterior wall of the recipient cava.
Many
patients undergoing liver transplantation are extremely ill and the surgery
involved can be very technically demanding. Optimal perioperative management is
crucial to a successful outcome and presents a major challenge. Blood loss
Technical
complications
Haemorrhage
Meticulous homeostasis during the transplant operation is important in
order to minimise the risk of early haemorrhage. It may occasionally be
necessary to pack the peritransplant area for 2—3 days to achieve adequate
haemostasis when there is diffuse oozing despite correction of coagulopathy.
Evacuation of extensive perihepatic haematoma may be required to avoid secondary
infection.
Vascular
complications
Hepatic artery thrombosis may occur spontaneously or as a result of
acute rejection, and is more common in paediatric recipients. It may present as
a rise in serum transaminase levels, unexplained fever or bile leak. Doppler
ultrasound or angiography are used to confirm the diagnosis and urgent retransplantation
is usually required. Portal vein thrombosis presents more insidiously and does
not usually require retransplantation.
Biliary
complications
Biliary leaks are now relatively uncommon and biliary stenosis is a
more common problem. It usually occurs late after transplantation and is managed
by endoscopic dilatation and stenting, and less often by surgical correction.
Paediatric
liver transplantation
Until recently, the major factor limiting paediatric liver
transplantation was the lack of suitably sized donor livers. However, as noted
earlier, the development of techniques for using adult livers that have been
reduced in size by cut-down techniques has greatly alleviated the problem. For
small children, the lateral segment of the left lobe is often used but the
entire left lobe or the right lobe may also be used in this way.
Outcome
after liver transplantation
The outcome after liver transplantation depends on the underlying
liver disease and the best results are seen in patients with chronic liver
disease (Fig. 11.20). Patients undergoing transplantation as a result of acute
liver failure have a higher mortality in the early post-transplant period
because of multiorgan failure, but those who make a satisfactory recovery have
very good long-term liver allograft survival. Conversely, patients transplanted
for tumour have a very good early outcome but ultimately fare much less well
because of recurrent malignancy. Patients receiving a liver transplant following
hepatitis B or hepatitis C infection often develop graft failure as a result of
recurrent viral disease.