Portal
hypertension
An elevation in portal pressure is most
commonly found accompanying liver cirrhosis, although it may be present in
patients with extra hepatic portal vein occlusion, intrahepatic veno-occlusive
disease or occlusion of the main hepatic veins [Budd—Chiari syndrome (BCS)].
As portal hypertension produces no symptoms it is usually diagnosed following
presentation with decompensated chronic liver disease and encephalopathy,
ascites or variceal bleeding.
Management of
bleeding varices
General resuscitation
Varices usually present with the acute onset of a large volume haematemesis, the lower oesophagus being the most common site for variceal bleeding. The diagnosis may be suspected if the patient is known to have liver cirrhosis but needs to be confirmed following initial resuscitation of the patient. This involves obtaining peripheral and subsequently central venous access whilst adequate blood is obtained (initially 10 units). Liver function tests will reveal underlying liver disease and a coagulation profile will reveal any underlying coagulopathy. Vitamin K is administered (10 mg intravenously), but correction of a coagulopathy will require the administration of fresh frozen plasma. An associated thrombocytopenia is usually secondary to hypersplenism due to cirrhosis and is treated if the platelet count falls below 50x109/litre. Variceal bleeding is often associated with hepatic encephalopathy, and endoscopic evaluation under these circumstances may require sedation and mechanical ventilation. Bronchial aspiration is a frequent complication of variceal bleeding.
If
the rate of blood loss prohibits endoscopic evaluation a Sengstaken—Blakemore
tube may be inserted to provide temporary haemostasis. This is shown diagrammatically
in (Fig.
Drug treatment for variceal bleeding
Vasopressin has been the most extensively used
drug for the initial control of variceal haemorrhage (20 units in 10 ml of 5
per cent dextrose intravenously over 10 minutes). Nitroglycerin (40 micro
gram/min)
may be as effective. Octreotide, the long-acting somatostatin analogue, has -
recently been evaluated and may have an important role.
Endoscopic treatment of varices
Initial treatment of oesophageal varices in
most centres would be endoscopic sclerotherapy using 5 per cent ethanolamine oleate. Banding has recently produced
encouraging results and is associated with a lower incidence of oesophageal
ulceration. The majority of variceal bleeds will respond to a single course of
sclerotherapy. An early re-bleed is less likely to be controlled by further
sclerotherapy and a third bleed only rarely.
Transjugular intrahepatic portosystemic stent shunts
(TIPSS)
The emergency management of variceal
haemorrhage has been revolutionised by the introduction of TIPSS in the early
1990s. Over a short period it has
become the main treatment of variceal haemorrhage which has not responded to
drug treatment and sclerotherapy. The shunts are inserted under local anesthetic, analgesia and sedation using fluoroscopic guidance and
Ultrasonography. Via the internal jugular vein and SVC a guide wire is inserted
into a hepatic vein and through the hepatic parenchyma into a branch of the
portal vein. The track through the parenchyma is then dilated with a balloon
catheter to allow insertion of a metallic stent which is expanded once a
satisfactory position is achieved (Fig. 52.12). A satisfactory drop in portal
venous pressure is usually associated with good control of the variceal
haemorrhage. The main early complication of this technique is perforation of the
liver capsule which can be associated with fatal intraperitoneal haemorrhage.
TIPSS occlusion may result in further variceal haemorrhage and occurs more
commonly in patients with well-compensated liver disease and good synthetic
function. Post shunt encephalopathy is the confusional state caused by the portal
blood bypassing the
Surgical shunts for variceal haemorrhage
The increasing availability of liver
transplantation and TIPSS has greatly reduced the indications for surgical
shunts. It is rarely considered for the acute management of variceal haemorrhage
as the morbidity and mortality under these circumstances are high. The main
current indication for a surgical shunt is a patient with Child’s grade A
cirrhosis in whom the initial bleed has been controlled by sclerotherapy.
Long-term beta-blocker therapy and chronic sclerotherapy or banding are the main
alternatives.
Surgical
shunts are an effective method of preventing re-bleeding from oesophageal or
gastric varices as they reduce the pressure in the portal circulation by
diverting the blood into the low-pressure systemic circulation. Shunts may be
divided into selective (e.g. splenorenal) and nonselective (e.g. portocaval),
the former attempting to preserve blood flow to the liver whilst decompressing
the left side of the portal circulation responsible for giving rise to the
oesophageal and gastric varices. Selective shunts may be associated with a lower
incidence of portal systemic encephalopathy (PSE), a confusional state
commonly found in patients with chronic liver disease who have undergone
radiological or surgical portosystemic shunts. The different types of surgical
shunts are shown in Fig. 52.13. There is no evidence that prophylactic shunting
is beneficial in patients with varices who have not bled.
Oesophageal stapled transection
This technique for the management of bleeding
oesophageal varices utilised the circular stapling device initially employed for
anastomosis of the rectum for stapling and resecting a ring of the lower
oesophagus. As with surgical shunts in the acute situation, it was associated
with a high perioperative mortality and has been largely abandoned in centres
where TIPSS is available.
Management of varices secondary to splenic or portal
vein thrombosis
Accurate angiography is an important aspect of
the assessment of patients with suspected extrahepatic portal vein thrombosis.
Therapeutic options are limited. Patients with
Variceal bleeding and liver transplantation
The management of variceal bleeding should
always take into account the possibility of liver transplantation where this is
available. The patient’s age or associated medical condition may be a
contraindication. TIPSS would be the preferred management for bleeds resistant
to sclerotherapy as long as placement is optimal. Previous surgical shunts
greatly increase the morbidity associated with OLT and probably the mortality.
Ascites
The accumulation of free peritoneal fluid is a
common feature of advanced liver disease independent of the aetiology. The
fluid accumulation is usually associated with abdominal discomfort and a
dragging sensation. Development is usually insidious. The aetiology of the
ascites must be established. Imaging by CT will confirm the ascites and
demonstrate the irregular and shrunken nature of a cirrhotic liver and associated
splenomegaly. Intravenous contrast enhancement will allow abdominal varices to
be demonstrated and patency of the portal vein, portal vein thrombosis being a
common predisposing factor to ascites in chronic liver disease. In patients
without evidence of liver disease malignancy is a common
Treatment of ascites in chronic liver disease
The initial treatment is to restrict
additional salt intake and commence diuretics using either spironolactone or
frusemide. This should be combined with advice on avoiding any precipitating
factors for impaired liver function, such as alcohol intake in patients with
alcoholic cirrhosis. Patients on diuretics should be monitored for the
development of hyponatraemia and hypokalaemia.
Abdominal paracentesis
Patients failing to respond to diuretic
treatment may require repeated percutaneous aspiration of the ascites (abdominal
paracentesis) combined with volume replacement using salt-poor or standard human
albumin solution dependent on the serum sodium level. This is an unsatisfactory
treatment but may provide some short-term symptomatic relief.
Liver transplantation for ascites
Diuretic-resistant ascites is an indication
for liver transplantation if associated with a deterioration in liver function
(rising bilirubin, dropping albumin, prolonged PT). The patient’s age,
underlying aetiology of liver disease and associated medical problems will be
the major factors determining
Peritoneovenous shunting
The Le Veen shunt is designed for the relief
of ascites due to chronic liver disease. One end of the silastic tube is
inserted into the ascites within the peritoneal cavity and it is then tunnelled subcutaneously to the neck, where it
is inserted under direct vision into the internal jugular vein and fed into
the SVC. Owing to a one-way valve within the tubing, peritoneal fluid is drawn
from the abdomen and drained to the circulation due to the lower pressure in
the SVC in comparison to the abdomen during the respiratory cycle. Although
often effective when combined with continued diuretic therapy they are prone
to occlude and become displaced or infected. In an attempt to prevent the high
occlusion rate a further development was the insertion of a chamber placed over
the costal margin to allow digital pressure and evacuation of any debris
within the peritoneo-venous shunt (Denver shunt).
TIPSS for ascites
The procedure and its limitations are as
outlined above for the emergency treatment of bleeding varices secondary to
portal hypertension. The use of TIPS S for ascites is for symptomatic relief,
and the procedure is associated with considerable risks including death from
haemorrhage, renal failure or heart failure. Post stent encephalopathy is common
(about 40 per cent) and the majority of stents will stenos on long-term
follow-up (approximately 50 per cent by- 1 year). Although a useful treatment
modality, it has not become widely
utilised because ascites is not life threatening. More encouraging results have
been obtained in those with persistent chylothorax.