الفهرس 
Anatomy of the LiverOnly 14 pages are availabe for public view
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Abstract
The discipline of liver transplantation has been developed
over the past decades, and liver transplantation is now
considered the gold standard for the treatment of patients with
end-stage liver disease. Increasing success rates has led to
broader indications and increased number of potential
recipients.
The patient selected for transplant should suffer from
irreversible, progressive disease for which there is no
acceptable, alternative therapy. Recipients are broadly defined
as having an intolerable quality of life because of liver disease
or having an anticipated length of life of less than 1 year
because of liver failure. Recipients are priority ranked by
application of the Model of End- Stage Liver Disease (MELD)
scoring system. The MELD system ranks patients by expected
mortality based on the severity of their liver disease.
Candidates for liver transplantation are subjected to
thorough evaluation and assessment of all body systems to
figure out all possible complications of end stage liver disease
as hepatorenal syndrome, hepatopulmonary syndrome and
hepatic encephalopathy. Liver function is also assessed through
all available laboratory and radiological methods. Finally they
are subjected to routine preanesthetic evaluation.
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Liver transplantation operation is conveniently divided
into three phases: preanhepatic, anhepatic, and neohepatic
phases. During the preanhepatic phase, a complete hepatectomy
is performed. During the anhepatic phase, vascular anastomoses
between the donor liver and the recipient’s vessels are
constructed. During the neohepatic phase, the hepatic arterial
and biliary anastomoses are constructed, and the wound is
closed.
Anesthesia for liver transplantation is divided into the
following phases:
1. Preinducion:
During the preinduction phase, the final evaluation of the
patient is performed and Last-minute laboratory results are
reviewed. then premedication and close monitoring of the
patient using standard monitors as pulse oximetry, ECG,
capnography and thermometry in addition to ivasive monitoring
as Central venous pressure monitoring, Pulmonary artery
catheterization, Invasive blood pressure, Transesophageal
echocardiography, Bispectral Index Monitoring. venovenous
bypass may be performed during this phase.
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2. Anesthetic Induction, Preparation for Surgery, and
Maintenance
Rapid sequence induction with cricoid pressure using
propofol 1 mg/kg and rocronium 1.2mg/kg is done. Analgesia is
achieved with short acting opioids as fentanyl. Maintenance is
either by propofol infusion or inhalational agents as sevoflurane
or isoflurane with care to interaction with immunosuppressant
drugs. Rapid infusion devices are prepared for possible blood
loss in next steps.
3. The Preanhepatic Phase:
This phase is characterized by hemodynamic instability
and coagulation defects. Hemodynamics is controlled either by
activating venovenous bypass or rapid infusion of fluids with or
without vasopressors as norepinephrine or vasopressin to
maintain perfusion of vital organs. Coagulation is closely
monitored with adequate correction of defects.
4. The Anhepatic Phase:
Hemodynamics is usually stable but Serum electrolyte
levels and acid–base balance are widely and rapidly swings.
This includes Acidosis, hyperkalemia, hypocalcemia and
hypoglycemia. Renal protection is a major concern.
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5. The Neohepatic Phase:
Graft reperfusion during this phase is associated with
variety of hemodynamic disturbances defined as
postreperfusion syndrome manifested as decrease in mean
arterial blood pressure. Acute clot lysis syndrome develops in
this phase phase manifested clinically as diffuse bleeding from
previously coagulated sites with elevation of the prothrombin
time. Management includes the use of antifibrinolytic agents
such as aprotinin, tranexamic acid, and ε- aminocaproic acid.
Finally the patient is prepared for transfer to the ICU usually
intubated.
The Postoperative care of hepatic transplant patients in the ICU
involves:
1. Stabilization and recovery of the major organ systems
(e.g., cardiovascular, pulmonary, renal), with patient
intubated and mechanically ventilated.
2. Evaluation of graft function and achievement of adequate
immunosuppression.
Monitoring and treatment of complications which may be
surgical or medical. Surgical complications include:
hemorrhage, thrombosis, biliary leak and wound infection.
Medical complications include: graft dysfunction, neurological
deficits, compromised cardiovascular and respiratory systems
and renal failure.