Portal hypertension

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Portal hypertension
Classification and external resources
The portal vein and its tributaries.
ICD-10	K76.6
ICD-9	572.3
DiseasesDB	10388
eMedicine	radio/570 med/1889
MeSH	D006975

In medicine, portal hypertension is hypertension (high blood pressure) in the portal vein system, which is composed of the portal vein, and its branches and tributaries.

Portal hypertension is defined as elevation of hepatic venous pressure gradient to >5mmHg. Generally, in clinical practice the pressure is not measured directly until the decision to place a transjugular intrahepatic portosystemic shunt (TIPS) has already been made. As part of that procedure an hepatic vein wedge pressure is measured with the assumption of no pressure drop across the liver yielding portal vein pressure.

Causes

Causes can be divided into prehepatic, intrahepatic, and posthepatic.

Prehepatic causes include portal vein thrombosis or congenital atresia.
Intrahepatic causes include liver cirrhosis, hepatic fibrosis (e.g. due to Wilson's disease, hemochromatosis, or congenital fibrosis), and less commonly noncirrhotic causes such as schistosomiasis, massive fatty change and diffuse granulomatous diseases (e.g. sarcoidosis, miliary tuberculosis).^[1]
Posthepatic obstruction occurs at any level between liver and right heart, including hepatic vein thrombosis, inferior vena cava thrombosis, inferior vena cava congenital malformation, and constrictive pericarditis.

Signs and symptoms

Consequences of portal hypertension are caused by blood being forced down alternate channels by the increased resistance to flow through the systemic venous system rather than the portal system. They include:

Ascites (free fluid in the peritoneal cavity).^[2]
Hepatic encephalopathy.
Increased risk of spontaneous bacterial peritonitis.
Increased risk of hepatorenal syndrome.
Splenomegaly (enlargement of the spleen) with a consequent accumulation of red blood cells, white blood cells, and platelets, together leading to mild pancytopenia.
Portacaval anastomoses: Esophageal varices, gastric varices, anorectal varices (not to be confused with hemorrhoids), and caput medusae. Esophageal and gastric varices pose an ongoing risk of life-threatening hemorrhage, with hematemesis or melena.

Diagnostics

HVPG (hepatic venous pressure gradient) measurement has been accepted as the gold standard for assessing the severity of portal hypertension,^[3] and replaced the old one - contrast angiography.^[4] Portal hypertension is defined as HVPG greater than or equal to 5mm Hg.^[5]

Treatment

Portosystemic Shunts

These can be categorized by several different concepts: selective vs non-selective, mesocaval vs portocaval, and the specific arrangement of vessels, e.g. end-to-side or side-to-side. Selective shunts select non-intestinal flow to be shunted to the systemic venous drainage while leaving the intestinal venous drainage to continue pass through the liver. The most well known of this type is the splenorenal, or Warren, shunt. This connects the splenic vein to the left renal vein thus reducing portal system pressure while minimizing any encephalopathy. In an H-shunt, which could be mesocaval (from the superior mesenteric artery to the inferior vena cava) or could be, unlikely, portocaval (from the portal vein to the inferior vena cava) a graft, either synthetic or the preferred vein harvested from somewhere else on the patient's body, is connected between the superior mesenteric vein and the inferior vena cava. The size of this shunt will determine how selective it is.

It should be noted that with the advent of TIPS, these are very rarely performed anymore. TIPS has the advantage of being much easier to perform and it doesn't disrupt any of the liver's vascular, which will be needed for a given patient's hoped for liver transplant. In general non-selective shunts are emergent surgeries that are done as quickly as possible to minimize intraoperative blood loss. On the contrary a splenorenal shunt would be an elective procedure due to its great technical demands. Further, contributing to their rare use today is the fact that few, if any, current general surgery residents are trained in how to carry out these surgeries.

Prophylaxis of variceal bleeding

Both pharmacological (non-specific ß-blockers like Propranolol and isosorbide mononitrate) and endoscopic (banding ligation) treatment have similar results. TIPS (transjugular intrahepatic portosystemic shunting) is superior to either of them at reducing rate of rebleeding. Disadvantages of TIPS include high cost and increased risk of hepatic encephalopathy, and it does not improve the mortality rate.

Management of active variceal bleeding

After resuscitation, which may require blood transfusion, the management of active variceal bleeding includes administering vasoactive drugs (somatostatin, octreotide or terlipressin), endoscopic banding ligation, balloon tamponade and TIPS(Transjugular intrahepatic portocaval shunt)

Management of ascites

This should be gradual to avoid sudden changes in systemic volume status which can precipitate hepatic encephalopathy, renal failure and death. The management includes salt restriction, diuretics (spironolactone), paracentesis, transjugular intrahepatic portosystemic shunt (TIPS) and peritoneovenous shunt.

Control of hepatic encephalopathy

A standard treatment plan may involve lactulose, bowel enemas, and use of oral antibiotics such as neomycin, metronidazole, vancomycin, and the quinolones. Previously, restriction of dietary protein was recommended but this is now refuted by a clinical trial which showed no benefit.^[6] Instead, the maintenance of adequate nutrition is now advocated.^[7]

References

↑ Perkins, [edited by] Vinay Kumar, Abul K. Abbas, Jon C. Aster ; artist, James A. Robbins basic pathology (9th ed. ed.). Philadelphia, PA: Elsevier/Saunders. p. 608. ISBN 978-1-4377-1781-5.
↑ "Portal Hypertension". Retrieved 2007-12-07.
↑ Damping Index of Doppler Hepatic Vein Waveform - Portal Hypertension: Discussion, http://www.medscape.com/viewarticle/564073_4
↑ Appleton & Lange's review for the ultrasonography examination, By Carol Krebs, Charles S. Odwin, Arthur C. Fleischer, page 309
↑ http://www.drfalkpharma.de/fileadmin/media/praesentationen/fs163/S4_P2.pdf
↑ Córdoba, J.; López-Hellín, J.; Planas, M.; Sabín, P.; Sanpedro, F.; Castro, F.; Esteban, R.; Guardia, J. (2004). "Normal protein diet for episodic hepatic encephalopathy: Results of a randomized study". Journal of Hepatology 41 (1): 38–43. doi:10.1016/j.jhep.2004.03.023. PMID 15246205.
↑ http://www.patient.co.uk/doctor/Hepatic-Encephalopathy.htm

External links

VIDEO - Portal Hypertension: Shunt Surgery in the Era of Transplant and TIPS, Alysandra Lal, MD, speaks at the University of Wisconsin School of Medicine and Public Health (2007)
Ascites at Merck Manual of Diagnosis and Therapy Home Edition
00863 at CHORUS
Overview at Cleveland Clinic
Children's Liver Disease Foundation

Digestive system, Digestive disease, Gastroenterology (primarily K20–K93, 530–579)

Upper GI tract

Esophagus	Esophagitis Candidal Herpetiform Rupture Boerhaave syndrome Mallory-Weiss syndrome UES Zenker's diverticulum LES Barrett's esophagus Esophageal motility disorder Nutcracker esophagus Achalasia Diffuse esophageal spasm Gastroesophageal reflux disease (GERD) Laryngopharyngeal reflux (LPR) Esophageal stricture Megaesophagus

Stomach	Gastritis Atrophic Ménétrier's disease Gastroenteritis Peptic (gastric) ulcer Cushing ulcer Dieulafoy's lesion Dyspepsia Pyloric stenosis Achlorhydria Gastroparesis Gastroptosis Portal hypertensive gastropathy Gastric antral vascular ectasia Gastric dumping syndrome Gastric volvulus

Lower GI tract:
Intestinal/
Enteropathy

Small intestine (Duodenum/Jejunum/Ileum)	Enteritis Duodenitis Jejunitis Ileitis Peptic (duodenal) ulcer Curling's ulcer Malabsorption: Coeliac Tropical sprue Blind loop syndrome Small bowel bacterial overgrowth syndrome Whipple's Short bowel syndrome Steatorrhea Milroy disease bile acid malabsorption

Large intestine (Appendix/Colon)	Appendicitis Colitis Pseudomembranous Ulcerative Ischemic Microscopic Collagenous Lymphocytic Functional colonic disease IBS Intestinal pseudoobstruction / Ogilvie syndrome Megacolon / Toxic megacolon Diverticulitis/Diverticulosis

Large and/or small	Enterocolitis Necrotizing IBD Crohn's disease Vascular: Abdominal angina Mesenteric ischemia Angiodysplasia Bowel obstruction: Ileus Intussusception Volvulus Fecal impaction Constipation Diarrhea Infectious Intestinal adhesions

Rectum	Proctitis Radiation proctitis Proctalgia fugax Rectal prolapse Anismus

Anal canal	Anal fissure/Anal fistula Anal abscess Anal dysplasia Pruritus ani

GI bleeding/BIS

Accessory

Liver	Hepatitis Viral hepatitis Autoimmune hepatitis Alcoholic hepatitis Cirrhosis PBC Fatty liver NASH Vascular Budd-Chiari syndrome Hepatic veno-occlusive disease Portal hypertension Nutmeg liver Alcoholic liver disease Liver failure Hepatic encephalopathy Acute liver failure Liver abscess Pyogenic Amoebic Hepatorenal syndrome Peliosis hepatis Metabolic Disorders Wilson's Disease Hemochromatosis

Gallbladder	Cholecystitis Gallstones/Cholecystolithiasis Cholesterolosis Rokitansky-Aschoff sinuses Postcholecystectomy syndrome Porcelain gallbladder

Bile duct/ Other biliary tree	Cholangitis PSC Secondary sclerosing cholangitis Ascending Cholestasis/Mirizzi's syndrome Biliary fistula Haemobilia Gallstones/Cholelithiasis Common bile duct Choledocholithiasis Biliary dyskinesia Sphincter of Oddi dysfunction

Pancreatic	Pancreatitis Acute Chronic Hereditary Pancreatic abscess Pancreatic pseudocyst Exocrine pancreatic insufficiency Pancreatic fistula

Abdominopelvic

Hernia	Diaphragmatic Congenital Hiatus Inguinal Indirect Direct Umbilical Femoral Obturator Spigelian Lumbar Petit's Grynfeltt-Lesshaft Undefined location Incisional Internal hernia

Peritoneal	Peritonitis Spontaneous bacterial peritonitis Hemoperitoneum Pneumoperitoneum

M: DIG

anat (t, g, p)/phys/devp/enzy

noco/cong/tumr, sysi/epon

proc, drug (A2A/2B/3/4/5/6/7/14/16), blte

Cardiovascular disease: vascular disease
Circulatory system pathology
- I70–I99, 440–456

Arteries, arterioles
and capillaries

Inflammation

Arterial occlusive disease /
peripheral vascular disease

Arteriosclerosis	Atherosclerosis Foam cell Fatty streak Atheroma Intermittent claudication Monckeberg's arteriosclerosis Arteriolosclerosis Hyaline Hyperplastic Cholesterol LDL Oxycholesterol Trans fat

Stenosis	Carotid artery stenosis Renal artery stenosis

Other	Aortoiliac occlusive disease Degos disease Erythromelalgia Fibromuscular dysplasia Raynaud's phenomenon

Aneurysm / dissection /
pseudoaneurysm

torso: Aortic aneurysm
- Abdominal aortic aneurysm
- Thoracic aortic aneurysm
Aortic dissection
Coronary artery aneurysm
head / neck
- Intracranial aneurysm
- Intracranial berry aneurysm
- Carotid artery dissection
- Vertebral artery dissection
- Familial aortic dissection

Vascular malformation

Vascular nevus

Veins

Inflammation	Phlebitis

Venous thrombosis / Thrombophlebitis	primarily lower limb Deep vein thrombosis abdomen Hepatic veno-occlusive disease Budd–Chiari syndrome May–Thurner syndrome Portal vein thrombosis Renal vein thrombosis upper limb / torso Mondor's disease Paget–Schroetter disease head Cerebral venous sinus thrombosis Post-thrombotic syndrome

Varicose veins	Gastric varices Portacaval anastomosis Caput medusae Esophageal varices Hemorrhoid Varicocele

Other	Chronic venous insufficiency Chronic cerebrospinal venous insufficiency Superior vena cava syndrome Inferior vena cava syndrome Venous ulcer

Arteries or veins

Angiopathy
- Macroangiopathy
- Microangiopathy
Embolism
Thrombosis
Vasculitis

Blood pressure

Hypertension	Hypertensive heart disease Hypertensive emergency Hypertensive nephropathy Essential hypertension Secondary hypertension Renovascular hypertension Benign hypertension Pulmonary hypertension Systolic hypertension White coat hypertension

Hypotension	Orthostatic hypotension

M: VAS

anat (a:h/u/t/a/l,v:h/u/t/a/l)/phys/devp/cell/prot

noco/syva/cong/lyvd/tumr, sysi/epon, injr

proc, drug (C2s+n/3/4/5/7/8/9)

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