portal hypertension
TRANSCRIPT
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