Hepatobiliary Surgery JC066: I Need A New Liver: Liver Transplantation Flashcards
Questions related to liver transplantation
- What are disease indications for liver transplantation?
- When should liver transplantation be performed?
- What are sources of liver graft?
- How is it being performed?
- What are the post-operative complications and medications?
- How successful is liver transplantation in the long run?
Indications for liver transplantation
- Fulminant hepatic failure
- Acute-on-chronic liver failure
- Chronic liver failure
- Metabolic diseases
- Small unresectable HCC
- Fulminant hepatic failure
- Severe liver injury, potentially reversible in nature with onset of hepatic encephalopathy **within 8 weeks of first symptoms (usually jaundice) in **absence of pre-existing liver disease
Causes:
1. Drug intoxication
- paracetamol
- halothane
- Food poisoning
- Amanita phalloides (mushroom) - Hepatitis
- Hep A, E
- Acute Hep B - Wilson’s disease
Clinical features of Acute hepatic failure
Clinical features:
1. Brain
- hepatic encephalopathy
- cerebral edema
- intracranial hypertension
- Lung
- acute lung injury - Liver
- loss of metabolic function
- hypoglycaemia
- lactic acidosis
- hyperammonaemia
- coagulopathy - BM
- suppression - Leukocytes
- impaired function —> high risk of sepsis - Heart
- high output state - Pancreas
- pancreatitis - Adrenal
- inadequate glucocorticoid production —> hypotension - Kidney
- dysfunction / failure - Portal hypertension
- Systemic inflammatory response
Management of Acute liver failure
Nursed in ***ICU
1. Organ support
- ***Metabolic support
- hypoglycaemia
- hypoNa - Monitor consciousness level
- indication for liver transplantation - ***Coagulopathy
- beware of procedures - ***Antibiotic prophylaxis
Hepatic encephalopathy
- may progress ***rapidly within days
- monitor closely + protect airway
Grading (0-4) on 3 aspects:
1. Consciousness / Intellect
- forgetfulness, irritability (grade 1)
- lethargic (grade 2)
- somnolent, aggressive (grade 3)
- coma (grade 4)
- Clinical features
- apraxia (grade 1)
- flapping tremor (grade 2)
- babinski +ve (grade 3)
- decerebrate (grade 4) - EEG
- slow 5 cps triphasic waves (grade 1-3)
- slow 2-3 cps delta waves (grade 4)
Subclinical (between 0 and 1): Normal Consciousness / Intellect + EEG except Psychomotor testing abnormality
Indication for Liver transplantation
King’s college criteria
- Irrespective of grade of encephalopathy
- PT >100s (INR >6.5)
or 3 of following:
- Age <10 / >40
- Duration of jaundice before encephalopathy >7 days (indicate low reversibility)
- PT > 50s (INR >3.5)
- Bilirubin > 300 umol/L
- Non-A, Non-B, Halothane or Idiosyncratic drug reaction, Wilson’s disease
For paracetamol poisoning:
- pH <7.3
or
- PT >100 + Creatinine >300 + Grade 3/4 encephalopathy
When NOT to transplant in Acute liver failure
- ***Uncontrolled infection
- e.g. severe bronchopneumonia, fungal septicaemia - Cerebral edema + ***coning
- may become vegetative state even after operation
Acute-on-chronic liver failure
Acute hepatic insult manifesting as:
- **Jaundice (serum bilirubin >90) + Coagulopathy (INR >1.5)
- Complicated within 4 weeks by **Ascites / Encephalopathy in a patient with ***previously diagnosed / undiagnosed chronic liver disease
Causes:
- Acute exacerbation / Flare of chronic Hep B
- Cirrhosis with acute deterioration
—> hepatic function ***decompensation (e.g. variceal bleeding)
—> death
Chronic liver failure
Causes:
- Cirrhosis (of any etiology)
—> **Hep B
—> **Hep C
—> **Alcoholism
—> **Primary biliary cirrhosis
—> Secondary biliary cirrhosis (chronic bile duct obstruction due to iatrogenic disease, biliary atresia in paediatrics —> ***longstanding biliary obstruction)
—> Autoimmune hepatitis
—> Budd-Chiari syndrome
***Clinical features of Chronic liver failure
- Malaise
- Jaundice
- Ascites
- Infection (spontaneous bacterial peritonitis)
- Bleeding esophageal varices
- Coma
Laboratory abnormalities:
1. ↑ INR
2. ↑ Bilirubin
3. ↓ Platelet
4. ↓ Serum albumin
5. ↓ WBC (∵ hypersplenism)
(6. ↑ NH3, ↓ Urea)
Complications of Cirrhosis
- HCC
- Portal hypertension
- Varices in stomach, esophagus —> Bleeding
- **Ascites —> Infection (spontaneous bacterial peritonitis) + Hernia, Hydrocele
- **Hypersplenism
- ***Encephalopathy - Liver dysfunction
- **Hepatopulmonary syndrome (↑ liver production / ↓ liver clearance of vasodilators, possibly involving nitric oxide —> **microscopic intrapulmonary arteriovenous dilatations —> **overperfusion relative to ventilation, leading to **VQ mismatch + hypoxemia)
- Ascites —> Infection (spontaneous bacterial peritonitis) + Hernia, Hydrocele
- ↓ Protein synthesis —> Malnutrition, **Immunosuppression, **Bleeding tendency
- ↓ Elimination of wastes —> **↑ Bilirubin, **Encephalopathy, **Hepatorenal syndrome (∵ activation of **RAAS due to portal hypertension —> renal vasoconstriction)
When to transplant in Chronic liver failure
- Worsening of liver function
- ↑ INR, ↑ Bilirubin, ↓ Albumin
- Complications of cirrhosis (esophageal bleeding, intractable ascites, unresectable HCC, spontaneous bacterial peritonitis)
Sources of donor liver grafts
- Living donor liver transplantation
- Deceased donor whole graft liver transplantation
- Deceased donor split liver transplantation
- Deceased donor reduced size liver transplantation
- Sequential liver transplantation
Demand for liver transplant: 15-20 per million population per year
HK brain dead organ donation rate: 4-6 per million population per year
Diagnosis of brain death
- ***Fixed + dilated pupils, not responding to light
- Absent corneal reflexes
- No motor response to painful stimuli
- No reflex activity except spinal cord reflex
- No oculocephalic reflex (doll’s eyes)
- No vestibulo-ocular reflexes
- No gag / cough reflex to bronchial stimulation
- No respiratory movements if mechanical ventilation stopped to ensure pCO2 >60 mmHg