Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

yr 3 GI > portal hypertension > Flashcards

portal hypertension Flashcards

1
Q

classification of causes of portal hypertension

A

prehepatic - blockage of the portal vein before the liver

hepatic

posthepatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

prehepatic causes of portal HTN

A

portal/splenic vein thrombosis

congenital atresia/stenosis

extrinsic compression - eg tumours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

hepatic causes of portal hypertension

A

cirrhosis - commonest UK

granulomata - sarcoid

myeloproliferative diseases

fibropolycystic disease - congenital hepatic fibrosis

schistosomiasis - commonest cause worldwide

hepatic mets

chronic hepatitis

idiopathic

nodular (nodular regnerative hyperplasia, partial nodular transformation)

toxins - arsenic, vinyl chloride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

posthepatic causes of portal hypertension

A

budd-chiari (hepatic vein obstruction)

CCF (RHF)

constrictive pericarditis

veno-occlusive disease

sclerosing hyaline necrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

sx of portal HTN

A

abdo swelling

haematemesis, PR bleeding or melaena - bleeding varices

jaundice

Lethargy, irritability and changes in sleep pattern - suggest encephalopathy.

Increased abdominal girth, weight gain - suggest ascites.

Abdominal pain and fever - suggest spontaneous bacterial peritonitis.

Pulmonary involvement is common in patients with portal hypertension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

signs of portal HTN

A

signs of underlying disease

splenomegaly - followed by signs of hypersplenism eg thrombocytopenia

signs from increased blood flow through portosystemic anastomoses

upper GI bleeding from portal hypertensive gastropathy, GI ulcers, or diffuse lower GI bleeding

encephalopathy

transudative ascites/oedema

venous hum heard over large upper abdo collaterals - loudest in inspiration

signs of liver failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

signs of portal HTN from increased blood flow through portosystemic anastomoses

A

through paraumbilical and epigastric veins = caput medusae

via rectal veins = haemorrhoidal or anorectal varices

via veins of the gastric fundis and distal 1/3 of oesophagus:

  • oesophageal varicies = risk of life threatening oesophageal variceal bleeding - haematemesis
  • gastric varices = melaena

impaired liver function (cirrhosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

complications of portal HTN

A

varices (+- haemorrhage)

ascites =

  • spontaneous bacterial peritonitis
  • hepatorenal syndrome
  • hepatic hydrothorax

portal hypertensive gastropathy - condition caused by cirrhosis or portal vein thrombosis -> gastrointestinal ulcers or diffuse lower GI bleeding

pul complications of portal HTN

  • portopulmonary HTN - pul arterial HTN
  • hepatopulmonary syndrome

cardiac cirrhosis

cirrhotic cardiomyopathy

liver failure

hepatic encephalopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

definition of portal HTN

A

abnormally high pressure in the hepatic portal vein

hepatic venous pressure gradient >=6mmHg

>10mmHg is clinically significant

>12mmHg is associated with complications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

causes of acute portal HTN

A

acute portal vein thrombosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

causes of chronic portal HTN

A

chronic thrombosis

cirrhosis

shistosomiasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Ix for portal HTN

A

bloods

imaging

  • US and doppler
  • abdo CT (spiral CT) - portal vein thrombosis
  • MRI
  • elasticity measurement - velocity of elsatic wave via an intercostally placed transmitter - results correlate with live rstiffness and so with fibrosis

oesophagogastroduodenoscopy - assessment and treatment of oesophageal varices

portal HTN measurement - hepatic venous pressure gradient - moderately invasive

liver biopsy - help find underlying cause

vascular imaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

US results for portal HTN

A

on duplex US

  • see cavernous transformation of portal vein - indicates chronic portal vein thrombosis
  • increased blood flow through portosystemic anastomoses
  • direction of flow

portal vein dilated to >12mm

splenomegaly

liver size

ascites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

medical Mx of portal HTN

A

1st line - non-selective B blocker (propranol/nadolol)

  • inhibits B2 adrenergic receptors in GIT = splanchnic vasoconstriction = reduced portal and collateral flow = reduced Portal HTN
  • prevent variceal bleeding

carvedilol - non-selective B blocker with anti-alpha1-adrenergic effects

pulmonary basoactive drugs (epoprostenol) - routine for idiopathic pulmonary HTN

vasoactive drugs - terlipressin and octreotide - reduce portal venous pressure, assist control of acute variceal bleeding

nitrates - added to B blocker - reduce portal pressure and rates of variceal re-bleeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

surgical Mx of portal HTN

A

transjugular intrahepatic portosystemic shunt

surgical portosystemic shunt - major surgery, less likely to stenose than TIPS

  • total portosystemic shunt
  • selective portosystemic shunt
  • partial portosystemic shunt

devascularisation procedure - gastro-oesophageal devascularisation, splenectomy, oesophageal transection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

transjugular intraheptaic portosystemic shunt

A
  1. needle catheter inserted via the internal jugular vein
  2. -> passed along to hepatic vein
  3. -> pierced through the liver parenchyma to intrahepatic branch of the portal vein
  4. -> expandable metal stent is placed
  5. -> side-to-side portocaval shunt

assures blood drainage from the portal to the systemic system bypassing the liver = lowering portal pressure, prevent re-bleeding from varices or the formation of ascites

17
Q

indication for transjugular intrahepatic portosystemic shunt (TIPS)

A

persistent, recurring or treatment resistant upper GI bleeding from portal HTN eg oesophageal varices/gastric varices

refractory ascites

acute thrombosis of portal vein

pts with hepatorenal syndrome who are not eligible for or who are awaiting liver transplantation

hepatic hydrothorax

hepatopulmonary syndrome

budd-chiari syndrome

18
Q

CI of transjugular intrahepatic portosystemic shunt

A

pre-existing hepatic encephalopathy or cirrhosis - shunt = reduced hepatic elimination of ammonia and worsening of encephalopathy

HF

severe pul HTN >44mmHg

uncontrolled systemic infection or sepsis

hepatic cysts or tumours

cavernous transformation of the portal vein following thrombosis

19
Q

total portosystemic shunt

A

portal vein completely shunted to vena cava = reduced portal pressure

20
Q

selective portosystemic shunt

A

portal vein is partially shunted to the vena cava = reduced portal pressure

prevents varices but allows portal perfusion

21
Q

aetiology of portal HTN from increased hepatic blood flow

A

increased splenic blood flow - eg massive splenomegaly

hepatoportal arteriovenous fistula

22
Q

L sided (sinistral) portal HTN

A

rare - confined to the L side of the portal system

may present as belleding from gastric varices

due to pathology incolbing the splenic vein or the pancreas

23
Q

things to look for in history of portal HTN

A

alcohol consumption

Blood transfusion, especially abroad; lifestyles that predispose to hepatitis B or hepatitis C.

Family history - eg, Wilson’s disease or hereditary haemochromatosis.

24
Q

signs of liver failure - portal HTN

A

Jaundice, spider naevi, palmar erythema.

Confusion, liver flap and fetor hepaticus are signs of encephalopathy.

Signs of hyperdynamic circulation: bounding pulse, low blood pressure, warm peripheries.

Enlarged or small liver.

Gynaecomastia and testicular atrophy

25
Q

blood results for portal HTN

A

LFT

UE

glucose

FBC

clotting screen

ix for liver disease if unknown cause:

  • ferritin - haemochromatosis
  • hepatitis serology
  • autoAb
  • alpha-1 antitrypsin
  • ceruloplasmin - wilson’s
26
Q

vascular imaging for portal HTN

A

site of the portal venous block can be demonstrated by examing the venous phase of a coeliac or superior mesenteric arteriogram, by splenic portography following injection of dye into splenic pulp, or by retrograde portography via hepatic vein

hepatic venography is helpful when hepatic vein block or idiopathic portal HTN is suspected

27
Q

conservative Mx of portal HTN

A

salt restriction and diuretics

28
Q

Mx of portal HTN

A

conservative

medical

TIPS

surgical

liver transplant - avoided in pts with portopulmonary HTN with severe pul HTN that is refractory to medical therapy

29
Q

endoscopic procedures for portal HTN

A

endoscopy - detect and monitor oesophageal varices

endoscopic vein ligation - prevent bleeding of oesophageal varices

For gastric varices with acute bleeding, endoscopic variceal obturation with tissue adhesives (eg, cyanoacrylate) complications - mucosal ulceration, thromboembolism

30
Q

complications of TIPS

A

hepatic encephalopathy and deteriorating liver function

stent may stenose

requires follow up and may require repeat procedures

31
Q

Mx of rectal varices

A

common in pts with portal HTN - dont usually bleed

located at anorectal junction

if they bleed - treatment similar to upper gastrointestinal varices

32
Q

hepatopulmonary syndrome

A

triad of hepatic dysfunction, hypoxaemia, extreme vasodilation in the form of intrapulmonary vascular dilations

33
Q

prognosis of portal HTN

A

depends on underlying disease and complications

34
Q

pathophysiology of portal HTN

A

increased vascular resistence in portal venous system

active process - liver damage activates stellate cells and myofibroblasts -> abnormal flow patterns

increased blood flow in portal veins, from splanchnic arteriolar vasodilation caused by excessive release of endogenous vasodilators

raised portal pressure opens up venous collaterals, connecting the portal and systemic venous systems

  • gastro-oesophageal junction = varices
  • anterior abdo wall - caput medusae, or where adhesions between abdo viscera and parietal peritoneum, or sites of stomas, or previous surgeyr
  • anorectal junction
  • veins from retroperitoneal viscera - communicate with systemic veins on posterior abdo wall

If individual tributaries of the portal vein are thrombosed, = local venous hypertension: splenic vein block = oesophageal and gastric varices

In Budd-Chiari syndrome (hepatic vein occlusion), collaterals open up within the liver; blood tends to be diverted through the caudate lobe whose short hepatic veins drain directly into the inferior vena cava.

Portosystemic venous anastomoses can cause encephalopathy, possibly due to various ‘toxins’ bypassing the liver’s ‘detoxification’ process.

35
Q

circulatory disturbances in portal HTN

A

portal HTN and cirrhosis = hyperdynamic circulation with splanchnic vasodilation, increased cardiac output, arterial hypotension, hypervolaemia

salt and water retention, ascites and hyponatraemia

yr 3 GI (52 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions