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06-08-2008, 07:26 AM
m Aetiology:
Liver cirrhosis, (most common).
Extrahepatic portal vein occlusion.
Intrahepatic veno-occlusive disease.
Occlusion of the main hepatic veins .
Ä As portal hypertension produces no symptoms it is usually diagnosed following presentation with decompensated chronic liver disease and encephalopathy, ascites or variceal bleeding.
m Management of Bleeding Varices:
Ä Clinical picture:
The lower oesophagus is the most common site for variceal bleeding.
Acute onset of a large volume haematemesis, if the patient is known to have liver cirrhosis.
Variceal bleeding is often associated with hepatic encephalopathy.
The diagnosis may be suspected but needs to be confirmed following initial resuscitation of the patient.
Ä Investigations:
Liver function tests will reveal underlying liver disease.
Coagulation profile will reveal any underlying coagulopathy. An associated thrombocytopenia is usually secondary to hypersplenism due to cirrhosis and is treated if the platelet count falls below 50 x 109/litre.
Endoscopic evaluation.
Ä Initial resuscitation:
Obtaining peripheral and subsequently central venous access. (initially 10 units blood should be obtained).
Vitamin K is administered (10 mg intra­venously), but correction of a coagulopathy will require the administration of fresh frozen plasma.
Sengstaken-Blakemore tube: If the rate of blood loss prohibits endoscopic evaluation a Sengstaken-Blakemore tube may be inserted to provide temporary haemostasis. Once inserted, the gastric balloon is inflated with 250 ml of air and retracted to the gastric fundus where the varices at the oesophagogastric junction are tamponaded by the subsequent inflation of the oesophageal balloon to a pressure of 40 mmHg. The two remaining channels allow gastric and oesophageal aspiration. An X-ray is used to confirm the position of the tube. The balloons should be temporarily deflated after 12 hours to prevent pressure necrosis of the oesopbagus.
Ä Complications of Sengstaken tube:
1- Asp. pneumonia but continuous aspiration from suction tube in the oesophagus can avoid.
2- Rupture of gastric balloon with rapid assent of oesophageal balloon to pharynx causing suffocation. Treatment rapid cutting of the tube and withdrawal of the ballon.
3- Pressure necrosis & ulceration causing more bleeding in its removal.
Ä Drug treatment for variceal bleeding
1- Vasopressin has been the most extensively used drug for the initial control of variceal haemorthage (20 units in 10 ml of 5 percent dextrose intravenously over 10 minutes).
Actions:
Increase systolic blood pressure which correct shock.
Cause splanchnic vasoconstriction portal pr.
Increase intestinal motility which help in evacuation of ammonia.
2- Nitro­glycerin (40 ug/min) may be effective.
3- Octreotide, the long-acting somatostatin analogue, has recently been evaluated and may have an important role.
ÄEndoscopic 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 selerotherapy. An early re-bleed is less likely to be controlled by further sclerotherapy and a third bleed only rarely.
Ä Emergency control of bleeding by surgical measures:
Indications:
1. Failure of the above measures to stop bleeding.
2. Massive bleeding unexpected to be controlled medically.
Types of operations:
1- Direct ligation of bleeding vessels either by transthoracic or transabdominal approach.
2- Hassab's operation: Splenectomy + vasoligation of the upper 2/3 of the stomach.
3- Tanner's gastric transection: The stomach is divided at the cardia then re-anastomosed {portosystemic disconnection}.
4- Stappler oesophageal transection either transoesophageal or transgastric.
5- Transjugular Intrahepatic Portosystemic Shunt (TIPS):
This is a minimally invasive way of creating a shunt between the portal vein and hepatic vein through the liver. A catheter is introduced through the jugular vein and under radiologic control positioned in the hepatic vein.
Ä Surgical shunts for variceal haemorrhage
The increasing availability of liver transplantation and TIPSS has greatly reduced the indications for surgical shunts.
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 β-blocker therapy and chronic sclerotherapy or banding are the main alternatives.
F Surgical shunts
Aim of operations: to reduce the pressure in the portal circulation by diverting the blood into the low-pressure systemic circulation.
1- Diversion of portal circulation to systemic (Total shunt procedure):
a) Porto caval shunt.
b) Splenorenal shunt.
c) Superior mesentricocaval shunt.
d) TIPSS
2- Selective decompression of oesphageal varices.
a) Distal lienorrenal shunt {Warren's operation}.
b) Left gastro caval shunt. {Inukoshi's shunt}.
3- Creation of wide portosystemic new anastomotic channels e.g. spleno-pneumopexy.
(I) Diversion of portal to systemic circulation (Total shunt):
Disadvantage of total shunts:
Portal blood reach brain encephalopathy.
blood supply to liver liver cell failure.
a) Porto-caval anastomosis:
a) End to side: Portal vein is transected near the liver. Hepatic end is ligated. Distal end is anastomosed with I.V.C .
b) Side to side: Some believe that it has lower incidence of encephalopathy
b) Lieno-renal shunt: "splenic vein to renal vein"
It cann't be done if the spleen previously removed or splenic vein is thrombosed.
c) Superior mesenterico caval anastomosis:
I.V.C. is devided near its lower end and the lower segment is ligated while the upper segment is anastomosed with the sup.mesenteric vein.
This operation is best done in children who can compensate ligation of I.V.C. In adult graft may be used between S.M.V. and I.V.C. {H-graft}
This H graft is simpler than others so, it is preferred in emergency.
d) Trans jugular intrahepatic portosystemic stent shunts (TIPSS)
It has become the main treatment of variceal haemorrhage which has not responded to drug treatment and sclerotherapy.
The shunts are inserted under local anaesthetic, analgesia and sedation using fluoroscopic guidance and ultrasonography. Via the internal jugular vein and SVC a guidewire 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. The main long-term complication to TIPSS is stenosis of the shunt, which is common (approximately 50 per cent at 1 year) and may present as further variceal haemorrhage.
(II) Selective decompression of varices: "Distal lienorenal shunt" [Warren's operation].
Splenic vein is devided near to portal vein. Portal end is ligated.
Splenic end is anastomosed to renal vein.
Spleen is not removed.
Ligation of Lt. gastric and Lt gastroepiploic vessels.
Lt. gastric V.

Short gastric veins.

Splenic vein.

Renal V.

Splenic vein

Now the varices are drained by short gastric veins to splenic vein to renal vein.





m Oesophageal Stapled Transection
This technique for the management of bleeding oesophageal varices utilized the circular stapling device 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.
m Management of varices secondary to splenic or portal vein thrombosis:
Splenic vein thrombosis may be seen secondary to chronic pancreatitis and portal vein thrombosis is a common late complication of liver cirrhosis.
Accurate angiography is an important aspect of the assess­ment of patients with suspected extrahepatic portal vein thrombosis.
Therapeutic options are limited: Oesophageal and/or gastric varices secondary to splenic or portal vein thrombosis can be effectively treated by splenec­tomy and gastro-oesophageal devascularisation, in which the blood supply to the greater and lesser curve of the stomach and lower oesophagus is divided.

m 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 of the stent is optimal, to avoid interfence with transplantation.
Previous surgical shunts greatly increase the morbidity associated with liver transplantation and probably the mortality.
m 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 prothrombin time). The patient's age, underlying aetiology of liver disease and associated medical problems will be the major factors determining
SOURCE: DR. AYMAN SALEM'S BOOK
Copyright: Vascular Society of Egypt (www.vsegypt.org (http://www.vsegypt.org/)) &Medical Educational web (www.meduweb.com (http://www.meduweb.com/))
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