Up ] Abdominal incisions ] Groin hernias ] Other hernias ] Peritonitis ] Appendicitis ] Ovarian cysts ] Oesophageal perforation ] Perforated peptic ulcer ] Diverticular disease ] Upper GI haemorrhage ] Lower GI haemorrhage ] Small bowel obstruction ] Large bowel obstruction ] Sigmoid and caecal volvulus ] Pseudo-obstruction ] Enterocutaneous fistulae ] Mesenteric ischaemia ] Acute pancreatitis ] Pyogenic liver abscess ] Amoebic liver abscess ] Hydatid disease ] Gynecological pain ] GORD ] Achalasia ] Oesophageal carcinoma ] Peptic ulcer disease ] Gastric carcinoma ] Hepatocellular carcinoma ] Pancreatic cancer ] Chronic pancreatitis ] Colonic polyps ] Colorectal carcinoma ] Liver metastases ] Anal carcinoma ] Inflammatory bowel disease ] Anal fissure ] Haemorrhoids ] Perianal sepsis ] Pilonidal sinus ] Rectal prolapse ] Jaundice ] Gall stones ] [ Portal hypertension ] Ascites ] Stomas ] Abdominal pain ] Abdominal masses ]

Portal hypertension

  • Normal portal pressure = 5 - 10 mmHg    
  • Portal hypertension is defined as a pressure > 12 mmHg

Aetiology

Prehepatic Intrahepatic Posthepatic
Portal vein thrombosis Presinusoidal Caval abnormality
Splenic vein thrombosis Schistosomiasis Constrictive pericarditis
Tropical splenomegaly Primary biliary cirrhosis
Arterio-venous fistula Chronic active hepatitis
Sarcoidosis
Sinusoidal
Cirrhosis - post hepatitic, alcohol, cryptogenic, metabolic (e.g. Wilson's, haemochromotosis)
Non-cirrhotic - cytotoxic drugs, Vitamin A intoxication
Postsinusoidal 
Budd-Chiari syndrome
Veno-occlusive disease

Pathophysiology

  • Increased portal pressure reduces portal venous flow
  • Encourages development of porto-systemic anastomoses
  • Develop at site of connections between portal and systemic circulation
    • Gastro-oesophageal junction
    • Lower rectum
    • Peri-umbilical veins
    • Retroperitoneal veins of Retzius
    • Peri-hepatic veins of Sappey

Clinical features

  • Cirrhosis is commonest cause of portal hypertension in the UK
  • Cirrhosis produces features of:
    • Hepatocellular failure
    • Portal hypertension
      • Variceal bleeding
      • Ascites
  • 90% patients with cirrhosis will develop oesophageal varices
  • Bleeding will occur in 30% of these patients

A caput medusa associated with cirrhosis

Severity of Cirrhosis
  • Severity can be assessed using Child-Pugh classification
    • Score 5-6 = Class A
    • Score 7-9 = Class B
    • Score > 10 = Class C
Variable Score
1 point

2 points

3 points
Encephalopathy Absent

Mild / moderate

Severe or coma

Bilirubin (μ mol/l)

<34

34-51 >51
Albumin (g/l) >3.5 2.8-3.5 <2.8
Prothrombin time (secs above normal) 1-4 4-6 >6

Management

  • In patients with known varices bleeding can be prevented by β blockers
  • Sclerotherapy does not prevent variceal bleeding
  • The role of TIPS in primary prevention is at present unknown

Surgical shunts

  • Portocaval shunts were commonly performed until the mid 1980s
  • Aim is to reduce portal pressure
  • Their use has decreased due to:
    • The introduction of TIPS
    • Liver transplantation in end stage liver disease
  • Shunts can be total, partial or selective
  • Role of shunts is to:
    • Emergency control of variceal bleeding when no access to TIPS
    • Reduce portal hypertension in patients awaiting transplantation
    • Relieve intractable ascites
    • Reduce bleeding from rectal, colonic or stomal varices

Total shunts

  • Have wide diameter and decompress all of portal circulation
  • There is no portal vein flow to the liver
  • Over 90% long-term patency can be achieved
  • 30-40% of patients will develop encephalopathy
  • Examples of total shunts are:
    • End-to-side portocaval shunt
    • Side-to-side portocaval shunt
    • Mesocaval C-graft
    • Central splenorenal shunt

Partial shunts

  • Have narrow diameter and partially decompress portal circulation
  • Some portal vein flow is maintained
  • Lesser procedure than total shunt
  • 20% will either stenose or occlude
  • 10% of patients will develop encephalopathy
  • Examples of partial shunts are:
    • Small bore portocaval H-graft

Selective shunts

  • Decompress part of portal circulation
  • Portal vein flow is maintained
  • Examples of selective shunts are:
    • Distal splenorenal shunt
    • Distal splenocaval shunt

Bibliography

Henderson J M.  Surgical treatment of portal hypertension.  Ballieres Best Pract Res Clin Gastroenterol 2000;  14: 911-925.

Menon K V,  Kamath P S.  Managing the complications of cirrhosis.  Mayo Clin Proc 2000;  75:  501-509.

Patel N H,  Chalasani N,  Jindal R M.  Current status of transjugular intrahepatic portosystemic shunt.  Postgrad Med J 1998;  74:  716-720.

 

 
 

Copyright 1997- 2013 Surgical-tutor.org.uk