Portal Hypertension Flashcards
What is the definition of portal hypertension?
- portal vein pressure > 12mmHg
- portal vein to hepatic vein pressure gradient greater than 5
What does the portal vein drain?
- lower esophagus
- stomach
- small & large intestines
- spleen
- pancreas
- gallbladder
Which veins form the portal vein?
Superior mesenteric vein & splenic vein
Which veins cause the varices in portal hypertension?
- umbilical & paraumbilical veins enlarge -> form umbilical varices
- coronary vein receives distal esophageal veins -> form esophago-gastric varices
What is the pathophysiology of portal hypertension?
- increase in vascular resistance: in cirrhosis -> mechanical consequence of hepatic architectural disorder
- > deposition of collagen in spaces of Disse
- > contraction of myofibroblasts
- increase in portal blood flow
Splanchnic arteriolar vasodilatation -> portosystemic collaterals
What are the prehepatic causes of increased vascular resistance?
- portal vein thrombosis
- splenic vein thrombosis
- congenital atresia or stenosis of portal vein
- extrinsic compression
- umbilical vein sepsis in children
What are the hepatic causes of increased resistance to flow?
- hepatic cirrhosis
- congenital hepatic fibrosis
- bilharzial peri-portal fibrosis
- lymphoma
- acute & fulminant hepatitis
- veno-occlusive disease
What are the post hepatic causes of increased resistance to flow?
- IVC obstruction
- right side heart failure
- constrictive pericarditis
- tricuspid regurgitation
- budd-chiari syndrome
What are the causes of increased blood volume of portal blood flow?
- Porto-hepatic fistula
- increased splenic flow (splenomegaly)
What are the consequences of portal HTN?
- enlargement of liver then shrinks with failure
- spleen enlarged with RES hyperplasia
- portosystemic shunt
- ascitis
- congestive gastropathy
How to determine the presence of complications?
- upper GI bleeding
- mental status change: lethargy, increased irritability, altered sleep patterns (portosystemic encephalopathy)
- increased abdominal girth (ascites formation)
- hematochezia & melena (bleeding from portal colopathy)
What are the signs of porto-systemic collateral formation?
- dilated veins in the anterior abdominal wall (umbilical epigastric shunts)
- caput medusa
- rectal varices
What will be seen on physical examination of person with portal hypertension?
- signs of porto systemic collaterals
- ascites (dullness in flanks with +ve shifting dullness & fluid thrill)
- splenomegaly
- paraumbilical hernia
- inguinal hernia or hydrocele
What are the signs of liver cell dysfunction?
- ascites
- jaundice
- spider angiomas
- palmar erythema
- testicular atrophy
- gynecomastia
- muscle wasting
What is the cause for morbidity & mortality in portal hypertension?
- variceal hemorrhage: most common
first episode has mortality of 30-50%
second episode has mortality of 80%
90% of patients with cirrhosis develop varices
What are the factors that lead to rupture and bleeding in esophageal varices?
food, reflux, & PHT causing ulcerations & erosions
Which varices are considered risky?
- > 15mm (1.5cm)
- unhealthy mucosa
- cherry red spots
What is the cause of splenomegaly in portal HTN?
EARLY -> toxins -> RE hyperplasia
LATE due to congestive splenomegaly -> 2ndry hypersplenism -> splenic infarction
What are the signs of GIT congestion?
- anorexia
- dyspepsia
- malabsorption
- gastric gastropathy
Whats the reason for ascities in portal HTN?
- increased aldosterone & ADH leads to salt & water retention
- increased hepatic transudation (WEEPING LIVER)
- hypo-albuminemia
- PHT is a localizing factor of the fluid into the peritoneal cavity
How should ascities be treated?
- best rest
- sodium restriction
- fluid restriction
- diuretics
- large volume paracentesis with 6-10g albumin/1L fluid
- TIPS
- LeVeen shunt & Denver shunt (peritoneovenous shunt)
- side to side portocaval shunt
What are the investigations done for portal HTN?
- assessment of liver function
- detection of varices (endoscope, barium swallow, Duplex)
- detection of hypersplenism (radioactive isotope, CBC, BM exam)
- liver biopsy, ultrasound
- pre-op measurement of portal HTN
What is the most effective method for screening for portal HTN & helps in diagnosing the cause?
DUPLEX ULTRASONOGRAPHY
- can demonstrate volume & direction of portal flow
- diagnoses the cause (PV thrombosis or splenic vein thrombosis)
How is portal pressure measured?
- hepatic venous pressure gradient (HVPG)
- wedge hepatic venous pressure WDVP - free hepatic venous pressure (FHVP)
What is Child’s classification?
predicts mortality of cirrhosis patients
bilirubin <2 2-3 >3
albumin >3.5 2.8 - 3.5 <2.8
PT 1-3 4-6 >6
ascites - slight moderate
encephalopathy - minimal advanced
1 2 3
A = 5-6 B = 7-9 C=10-15
When should endoscopy be performed?
- all patients with cirrhosis should be screened for presence of varices at initial diagnosis of cirrhosis
- in grade A (5-6) compensated patients without varices: repeat endoscopy every 2-3 years
- in compensated patients with small varices: endoscopy every 1-2 years
- in patients with risky varices: measures should be taken before bleeding (injection/banding using endoscopy)
How should bleeding varices be managed?
1- admission
2- resuscitation (wide bore cannula central line catheter)
3- correct coagulopathy (fresh blood - FFP - vit K)
4- prevent encephalopathy: oxygenation - warm patient - neomycin - NG tube to remove blood)
5- stop bleeding (endoscopic ligation/sclerotherapy in hemodynamically stable OR balloon tamponade)
6- Pharmacological therapy (octreotide, somatostatin, nitroglycerin)
What is the cause of encephalopathy?
bacteria + blood -> fermentation ===== ammonia
What are the types of tubes used in tube tamponade?
Minnesota tube
Sungestaken-Blackmoore tube
How is the Sungestake Tube used to stop the bleeding?
TRIPLE WAY - gastric balloon = 150cc saline - esophageal balloon = 35mmHg air - Ryle = suction & wash leave it 24h then deflate in place for 8hr USED IN SHOCKED PATIENTS
What pharmacological therapy is used in emergency treatment?
- Somatostatin to decrease portal flow + nitroglycerin
- octreotide
- vasopressin + nitroglycerin: splanchnic vasoconstrictor, decreases portal pressure
What surgeries are used in emergency management of portal hypertension?
- shunt surgery
- esophageal transection
What are the indications for shunt surgeries?
- intractable bleeding
- failed endoscopic management
- recurrent bleeding
- in preparation for liver transplant
What are the types of shunt surgeries used in portal HTN?
- end-to-side portocaval shunt: increases encephalopathy because no filtration of blood will occur in the liver
- side-to-side portocaval or mesocaval: less encephalopathy
- splenorenal: proximal (nonselective + splenectomy) OR distal (selective)
What are the types of selective shunts?
Corono-caval (non-selective)
Warrem-Sallam (distal spleino-renal) (selective)
- decompress varices while maintaining PV
- decompresses GE varices through short gastric & splenic vein to left renal vein
- looses selectivity over time
What should be the first choice for shunt surgery in portal hypertension?
TIPS (transjugular intrahepatic porto-systemic shunt)
- Palmaz balloon expandable stent is introduced through jugular vein to reach hepatic vein -> enters branch of portal vein -> creates porto-systemic shunt
When is liver transplantation indicated in portal hypertension?
CHILD C PAtiENTS
- relives portal hypertension, prevents bleeding, manages ascites & encephalopathy
