Portal hypertension

By

Dr. Gunjan Malviya

Content• Definition• Pathophysiology• Classification• Clinical Features• Management

Definition-An elevation of portal pressure above 10-12 mm Hg or 30 cm of saline or intrasplenic pressure>17 mm Hg or wedged hepatic venous pressure more than 4 mm Hg above inferior vena caval pressure.

Pathophysiology

• portal system includes all veins,which carry blood from digestive tract,spleen pancreas and gall bladder to liver via portal vein

• portal vein is formed by the union of superior mesenteric vein and splenic vein just posterior to neck of pancreas at level of L 2

Portal venous System

• portal vein about 6-8 cm long and 12 mm in diameter

• It dose not contain any valves and hence the pressure is same in all part of portal venous system.

• it supplies the liver 80% of blood and 20 % of oxygen

• the portal system is peculiar in that it begins as capillaries in mesentery of the intestine and spleen and end as capillaries in liver

classification of PHT

1Pre hepatic PTH

2.Intra hepatic PTH- 1.pre sinusoidal

2.sinusoidal

3.post sinusoidal

3.post-hepatic PTH

Pre hepaticPHT

1.Upper GIT bleeding2.pallor3.splenomegaly

PRESINUSOIDAL SINUSOIDAL

1.upper GIT bleeding2.splenomegaly

3.jaundice4.hepatomegaly

5.ascites6.hepatic encephalopathy

PORTAL HYPERTENSION

post sinusoidalpost hepatic

abdominal pain with vomitingmassive ascites

tender hepatomegalyupper GIT bleeding

jaundice

splenomegalyupper GIT BLEED

the combination of GIT bleed and splenomegaly is pathognomonic of PTH.

left lobe of liver enlarged in intr hepatic PTH and caudate lobe enlarged in post hepatic PTH

PRE HEPATIC PORTAL HYPERTENSION

block in portal vein occurs before the blood reaches the liver.

• Patients usually present with upper GIT bleeding,

• normal liver function and, prognosis excellent.

AETIOLOGY

1. Developmental defects-Portal vein agenesis, atresia, stenosis, cavernoma.

2. umbilical sepsis-this is most important cause in developing countries

umbilical vein

left branch of portal vein

portal vein

infected thrombus

3. trauma

4.Portal vein thrombosis

5.Intra-abdominal infections-like acute appendicitis and primary peritonitis and pancreatitis.

6.idiopathic-IN 50 % OF children with pre hepatic PTHetiology can not be found out.

CLINCAL FEATURE OF PRE HEPATIC PTH

UPPER GIT BLEED-due to ruptured oesophageal varices

Manifestation of upper GI bleed hematemesis-vomiting of fresh blood melaenemesis-vomiting of altered blood. melena-passage of

black,tarry,sticky,offensive,loose stools.

On General Examination

• pallor• splenomegaly• stunted growth-stunted growth due to the following

factors- 1. massive splenomegaly compresses the stomach. 2.deprivation of hepatotrophic growth factors • no jaundice• no hepatomegaly• no ascites

Intra Hepatic PTH

• TYPES- 1.pre sinusoidal 2.sinusoidal 3.post sinusoidal• the liver functions are usually normal in

pre sinusoidal ,where they are dearrenged in sinusoidal and post sinusoidal.

pre sinusoidal PTH

1. chronic active hepatitis2.congenital hepatic fibrosis3.chronic myeloid leukemia4.systemic mastocytosis5.sarcoidosis6.primary biliary cirrhosis7. schistosomiasis

sinusoidal PTH

this is cause by cirrhosis due to hepatitis B and C ,metabolic disorders like wilson's disease,cholestasis disorders like biliary atresia,neonatal hepatitis,drugs like INH,methotrexate.

feature-1.upper GIT bleed 2.splenomegaly 3.jaundice 4.ascites 5.hepatic encephalopathy 6.caput medusa 7.hepatomegaly

smith-Howard syndrome:- sometimes the spleen become impalpable following a massive bleed,which may cause diagnostic confusion this condition is called smith-Howard syndrome.

size of spleen dose not correlate well with portal hypertension.

ascites is a frequent problem in sinusoidal and post sinusoidal PTH. It is not usually seen in pre hepatic and pre sinusoid PTH

POST SINUSOIDAL PHT(VENO-OCCLUSIVE disease)

• This is non thrombotic occlusion of terminal hepatic venous radicles without associated abnormality of hepatic vein or inferior vena cava.

AETIOLOGY- TOXINS LIKE aflatoxins drugs like 6-mercaptopurine,

cyclophosphamide,vincristine hypervitaminosis A.

fibroblastic proliferation

endothelial edema

phlebosclerosis

toxin and drugs, and hypervitaminosis

occlusion of vein

POST HEPATIC PTH(Budd- chiari syndrome)

thrombosis of hepatic vein. etiology-A.Thrombosis complicating- 1.abdominal trauma 2.polycythemia rubra vera 3.neoplasms 4.S.L.E 5.cirrhosis 6.sickle cell anaemiaB.membranous obstruction of supra hepatic vena

cava

• acute budd chiari syndrome-1. sever abdominal pain with vomiting 2. mild jaundice3.ascites

chronic budd chiari syndrome1.massive ascites2.hepatomegaly3.upper GI bleed4.hypertrophy of the caudate lobe.5.compression of the intrahepatic portion of the IVC, leading to

lower extremity edema

MANAGEMENT of Upper GIT BleedMANAGEMENT of Upper GIT Bleed

INVESTIGATION• CBC• LFT-dearrenged in sinusoidal,post sinusoidal and post hepatic portal

hypertension.normal in pre sinusoidal and pre hepatic PHT..

USG• portal vein diameter >17mm• portal vein not increases in diameter during inspiration.• demonstration of collaterals

• splenomegaly

color Doppler-assess the blood flow within the portal vein

Upper GIT ENDOSCOPY

• demonstration of

oesophageal varices,

gastric varices

TREATMENT

primary prophylaxis

propranolol- dose -:1-2 mg /kg/day mechanism of action-it lowers the venous

pressure and portal venous pressure by decreasing the heart rate by 25% and the blood pressure by 15 mm Hg.It also causes splanchnic vasoconstriction.

Treatment of bleeding esophageal varices

• fluid resuscitation- i.v. fluids and blood transfusion to correct hypovolemia in a patient with massive upper GIT bleeding.

• The first step is to assess the degree of blood loss by the following methods:-

1.disproportionate tachycardia,suggest that the patient has lost about 20 % of blood volume.

2.TILT TEST-the basal pulse rate and BP are measured.The head end of the patient is then tilted or raised to 45 degree, so as to produce postural hypertension.

if the pulse rate rises by more than 20/min or if the diastolic BP falls by more than 10 mm of mercury,the patient has suffered about 25% blood loss.

3. Capillary refill sign In a normal person if the nail bed is compressed

and the pressure released, the blood column comes back almost immediately. But if the patient has lost the blood 25% blood volume it take more than 5 sec to come back.

4. If the patient is in shock, he has lost about 40% blood volume.

• use of Nasogastric tube to confirm active bleeding

• normal saline at room temperature is best for gastric lavage

• chilled or iced saline gastric wash does not stop bleed and may cause central hypothermia.

Pharmacological therapy

1.vasopressin0.33 u/kg in 20 min than iv infusion of 0.33U/kg/hr

2.octreotideadministered by continuous intravenous infusion of 1.0-5.0 µg/kg/hr

H2 blocker/PPI

I.V. vit k

Endoscopic therapy variceal band

ligation-it is gold standard treatment for esophageal varices.less bleeding,fewer complication and requires fewer treatment sessions to achieve variceal eradication than sclerotherapy.

B.variceal sclerotherapy-via endoscope sclerosing agent is injected in lumen of each varix,causing thrombosed.endoscopy is usually repeated with in 48 hr than weekly interval.

• sclerosant used in esophageal varices-

1.ethalonamide oleate

2.absolute alcohol

3.phenol

4.butyl cyanoacrylate

Disadvantage of sclerotherapy

• chances of re bleeding is high (>25%) hence repeated injections are necessary

• multiple esophageal ulceration

• esophageal stricture

• paraplegia

Trans jugular Intrahepatic Porto-systemic Shunt

• TIPSS is percutaneous technique creates communication between the right hepatic vein and the right or left branch of the portal vein

• performed if failed medical and endoscopic management

Surgical procedure

• Surgical porto-systemic shunts (often spleno-renal)

• De vascularization surgery• Liver transplantation

• creation of an anastomosis between portal and systemic venous system.

• most common anastomosis between splenic vein and left renal vein.

Surgical porto-systemic shunts

Surgical porto-systemic shunts

child-pugh scorechild-pugh scorefeatures 1 2 3

bilirubin(mg%) 1-2 2-3 >3

ascites absent slight moderate

prothrombin time <4 sec4-6 sec >6 sec

serum albumin >3.5g 2.8-3.5g <2.8g

encephalopathy

(stage)none 1-2 3-4

child's criteria are useful guide for deciding the suitabilityof a patient for shunt surgery and prognosis

grading points prognosis

grade A 5-6liver function is maintained.<10% mortality in surgical procedure

grade B 7-9 intermediate

grade C 10-15poor.

>90% mortality in surgical procedure

Devascularization surgery

• transthoracic para-esophageal devascularization is combined with esophageal transection, splenectomy, esophagogastric devascularization, truncal vagotomy and pyeloplasty.

Liver transplantation

• Orthotopic liver transplantation represents a much better therapy for portal hypertension resulting from intrahepatic disease and cirrhosis

portal hypertension

PRIMARY Prophylaxis

propranolol-dose 1 mg /kg/day

Bleeding esophageal varices

iv fluids and blood transfusionvit k

H2 blocker or PPI

after bleeding episodeor bleeding is not stop

pharmacological drugs

sengstaken-blackemore tube

surgical procedurede vascularization

porto-systemic shunt

liver transplantation

bleeding persists

TIPSS

EST/ EVL

Pathophysiology Of Ascites In Portal Hypertension

portal hypertension

hypovolaemia

activation of renal angiotensin-aldosterone

system(RAAS)

increase Na and waterreabsorption from DCT

renin

Ascitesexpansion of plasma

increase pressure in sinusoid

protein rich fluid from sinusoids into hepatic lymphatics

causing increased hepatic lymph

excess lymph enter into theperitoneal cavity

Management OF Ascites• In 80% of cases ,ascites is caused by cirrhosis

• in portal hypertension transudate ascites occur.

• Serum -Ascites Albumin Gradient (SAAG) is useful for distinguishing ascites caused by portal hypertension from non-portal hypertension ascites.

• SAAG=(ascites albumin -serum albumin).

• SAAG>1.1g/dl :- presence of portal hypertension.

SAAG

>1.1 g/dl

Ascitic protein <2.5g/dl

cirrhosislate budd-chiari syndrome

massive metastases

Ascitic protein_>2.5g/dl

congestive heart failure/constrictivepericarditis

early budd-chiari syndromeIVC obstruction

post sinusoidal PTH

<1.1g/dl

biliary leaknephrotic syndrome

pancreatitisperitoneal carcinoma

tuberculosis

Management of ascites-Bed Rest

Bed rest : • Upright posture activates sodium retaining

mechanisms , impairs renal perfusion and sodium excretion.

Sodium Restriction

Sodium restriction : A negative Na balance can attained by

restricting oral intake of salt 2 g/day.

WATER RESTRICTION

• Central hypovolaemia - > stimulates ADH receptors - > decreases free water clearance - > dilutional

hyponatraemia. • Restriction of water worse> central hypovolaemia.

DIURETICS

• potassium -sparing diuretics is considered the diuretic of choice in portal hypertension.

• hyper aldosteronism promotes sodium retention in distal tubules and collecting ducts in portal hypertension

• this action is inhibited by spironolactone.• loop diuretics act on thick ascending limb of henle by

inhibiting Na-k-2Cl symport,preventing the reabsorption of Na and water.there is hperaldosteronism In portal hypertension.so Na and water absorbed from the DCT.so loop along is not effective.

• spironolactone is not a powerful natriuretic agent .As mono therapy,it takes several days to induce weight loss.hence it is preferable to use a combination of spironolactone and furosemide.

• Dose of spironolactone-start with 1mg/kg and increase at rate of 1mg/kg/day to a maximum of 6 mg/kg/day.

Assess response to diuretics • Weight loss of 0.5kg/day in absence of edema and

1kg/day when edema present.• Use Spironolactone & Furosemide 100mg/40mg

ratio

Refractory ascites

• Definition-ascites does not respond to salt restriction and diuretics.

• Therapeutic options in refractory ascites-:1.Serial Paracentesis2.Peritoneovenous Shunts3.TIPSS4.Liver Transplantation

Peritoneo-venous shunt

• ascitic fluid is shunted from the high pressure peritoneal cavity to the low pressure superior vena cava by

1.Le veen shunt

2.denver shunt