FN: Portal Hypertension Flashcards
Hepatic Causes
Hepatic: cirrhosis (80% in UK), schisto (commonest
worldwide), sarcoidosis.
Pre-hepatic causes
portal vein thrombosis (e.g. pancreatitis)
Post-hepatic causes
Post-hepatic: Budd-Chiari, RHF, constrictive
pericarditis, TR
Portosystemic anastomoses effect
Oesophageal varices
Caput medusae
Haemorrhoids (worsened)
Oesophageal varices portal source and systemic
- Left and short gastric veins
- Inf. oesophageal veins
Caput medusae portal and systemic
- Peri-umbilical veins
- Sup-rectal veins
Haemorrhoids portal and systemic source
- Sup-rectal veins
- Inf. and mid, rectal veins
Prominent abdominal veins
A lot more common than caput medusa
Blood flow down below the umbilicus: portal HTN
Blood flow up below the umbilicus: IVC obstruction
Encephalopathy pathophysiology
↓ hepatic metabolic function
Diversion of toxins from liver directly into systemic
system.
Ammonia accumulates and pass to brain where
astrocytes clear it causing glutamate → glutamine
↑ glutamine → osmotic imbalance → cerebral oedema.
Classification of encephalopathy
1: Confused – irritable, mild confusion, sleep inversion
2: Drowsy – ↑ disorientated, slurred speech, asterixis
3: Stupor – rousable, incoherence
4: Coma – unrousable, ± extensor plantars
Presentation of encephalopthy
Asterixis, ataxia Confusion Dysarthria Constructional apraxia Seizures
Precipitants - HEPATICS
Haemorrhage: e.g. varices Electrolytes: ↓K, ↓Na Poisons: diuretics, sedatives, anaesthetics Alcohol Tumour: HCC Infection: SBP , pneumonia, UTI, HDV Constipation (commonest cause) Sugar (glucose) ↓: e.g. low calorie diet
Ix in encephalopathy
raised plasma NH4
Treatment of encephalopathy
- Nurse 20 degrees heads up
- Correct any precipitants
- Avoid sedatives
- Lactulose ± PO4 enemas to ↓ nitrogen-forming bowel
bacteria → 2-4 soft stools/d
- Consider rifaximin PO to kill intestinal microflora ©
Sequelae of portal Hypertension
Splenomegaly Ascites
Varices
Encephalopathy
Ascites pathophysiology
Back-pressure → fluid exudation
↓ effective circulating volume → RAS activation
(In cirrhosis: ↓ albumin → ↓ plasma oncotic pressure
and aldosterone metabolism impaired)
symptoms of ascites
Distension → abdominal discomfort and anorexia Dyspnoea
↓ venous return
Differential of ascites
Serum Ascites Albumin Gradient (SAGG)
SAAG >1.1g/dL =
Portal HTN (97% accuracy)
Pre-, hepatic and post
Cirrhosis in 80%
SAAG < 1.1g/dL
Other Causes
Neoplasia: peritoneal or visceral (e.g. ovarian) Inflammation: e.g. pancreatitis
Nephrotic Syndrome
Infection: TB peritonitis
Investigations
1. Bloods: FBC, U+E, LFTs, INR, chronic hepatitis screen
2. US: confirm ascites, liver echogenicity, PV duplex
3. Ascitic tap
- MCS and AFB
- Cytology
- Chemistry: albumin, LDH, glucose, protein - SAAG = serum albumin – ascites albumin
4. Liver biopsy
Treatment
Daily wt. aiming for 0.5kg/d reduction
Fluid restrict <1.5L/d and low Na diet
Spironolactone + frusemide (if response poor)
Therapeutic paracentesis ̄c albumin infusion (100ml
20% albumin /L drained)
Respiratory compromise Pain / discomfort
Renal impairment
Refractory: TIPSS
SBP
Pt. ̄c ascites and peritonitic abdomen
E. coli, Klebsiella, Streps
Complicated by hepatorenal syn. in 30%
Ix: ascitic PMN > 250mm3 + MC+S
Rx: Tazocin or cefotaxime until sensitivities known
Prophylaxis: high recurrence cipro long-term
Splenomegaly
Splenic congestion Hypersplenism: ↓ WCC, ↓ plats