Liver Transplant

Question 1

A 56-year-old male patient is undergoing a liver transplant. You are asked to
review him on the ward prior to anaesthetising him.

What are the indications for a liver transplant?

Answer 1

• Decision made by using the UKMELD (UK Model for End Stage Liver Disease) score. This is calculated using the patient’s serum bilirubin, creatinine, sodium and INR. The score is a predictor of morbidity and mortality and is used in the prioritisation of organs.

Common indications for a liver transplant are:
* Liver cirrhosis (viral, alcoholic and autoimmune).
* Malignancy.
* Acute liver failure (including due to overdose).
* Metabolic conditions e.g. Wilson’s disease.
* Failed previous transplant.

Question 2

What key features in this patient’s history would you like to determine with regards to his chronic liver disease?

Answer 2

• The cause and duration of his liver disease.
• Conditions related to the cause of the liver disease e.g. alcohol-
  induced cardiomyopathy.
• The presence of any systemic complications of chronic liver disease,
  including:
• Portal hypertension.
• Splenomegaly.
• Gastric/oesophageal varices.
• Ischaemic heart disease/cardiomyopathy.
• Hepatopulmonary syndrome.
• Hepatorenal syndrome.
• Anaemia.
• Hepatic encephalopathy.

Question 3

What is platypnea-orthodeoxia syndrome?

Answer 3

• This is a collection of symptoms that can occur secondary to hepatopulmonary syndrome, where the patient experiences shortness of breath and desaturation when moving from a lying to a sitting position.
• This is due to intrapulmonary arteriovenous shunting and ventilation/perfusion mismatch.

Question 4

What investigations should be considered when working up a patient for a liver transplant?

Answer 4

• Blood tests including:
• Full blood count (to check for anaemia and thrombocytopaenia).
• Clotting assessment including both in vitro and laboratory (with
  thromboelastography).
• Renal function (to assess for hepatorenal syndrome and electrolyte disturbances due to chronic water retention).
• Cardiac testing: ECG, echo.
• Pulmonary function tests.
• CPET for dynamic cardiorespiratory function.
• Imaging: ultrasound, abdominal MRI if there is a surgical indication.
• Psychological evaluation.

Question 5

What dose adjustments for drugs during the anaesthetic should be considered for this patient?

Answer 5

• Propofol: The dose should be decreased due to the increased risk of severe hypotension on induction.
• Volatile anaesthetic agents: Titrate the dose carefully due to the depressant effect on the cardiovascular system. Depth of anaesthesia monitoring may be helpful. Minimal hepatic excretion with desflurane and faster wake-up may be beneficial.
• Neuromuscular blocking agents: This patient may need an increased initial dose due to the increased volume of distribution/decreased protein binding in patients with chronic liver disease but care with rocuronium (hepatic excretion), which may accumulate.
• Opioids: Doses should be titrated carefully due to the risk of accumulation. Shorter acting agents are recommended.

Question 6

What are the perioperative anaesthetic concerns when anaesthetising a patient for a liver transplant?

Answer 6

• This is a high-risk comorbid patient for a prolonged major abdominal procedure.
• Risk of significant preoperative metabolic, clotting, renal and fluid imbalance.
• Risk of major haemorrhage due to pre-existing clotting abnormalities and a highly vascular organ.
• High incidence of metabolic acidosis and severe electrolyte disturbance during the anhepatic phase causing severe cardiovascular instability.

Question 7

What are the potential postoperative complications in this patient?

Answer 7

Early:
* Haemorrhage.
* Acute graft rejection.
* Hepatic vein/artery thrombosis.
* Sepsis.
* Renal failure.

Late:
* Infection.
* Graft rejection.
* Side effects of immunosuppressant agents.
* Liver failure due to recurrence of the initial disease.