الفهرس 
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Abstract
SUMlVIARy
Liver is probably the most complex organ in the body
involved in a multitude of metabolic. hormonal. enzymatic
processes. as well as a clearing site for the metabolism of
drugs and other substances ingested. It is the major organ
of drug metabolism. so special care should be taken in
adminstering drugs and anaesthetices to patients with
diseases that modify hepatic and metabolic function.
Liver blood flow is about 20% of c.o.p. different kinds
of intravenous. inhalational and regional anaesthesics cause
a decrease in hepatic blood flow during anaesthesia due to
foIl in c.o.p. and decrease in total peripheral resistance.
The:nduction and maintenance of anaesthesia produce a
DROP up to 50% in hipatic blood flow.
Halothane has been reported to produce hepat:t:s which
may be either autoimmune or due to effect of reduct:ve.
metabolites in the hypoxic liver in presence of enzymat:c
induction. Enflurane hepatic injury is very rare.
Isofluoane is biologically staple compared with other
agents. and it has demonstrated no hepatotoxicity in animals
orin hwnans.
Liver transplantation has been carred out for a large
variety of acute and chronic. primary and secondary liver
diseases.
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Liver transplant surgery posses unigue problems in
perioperative management. patients undergoing liver
transplantation presend a wide spectrum of pathophysiogical
changes which mandates thorerative assessment. Nearly every
organ system has been involved. and this includes
cardiopulmonary instability :renal dysfunction and
hepatorenal syndrome: eleectrolyte disoders and asid-base
imbalanse: hypoglycaemia: hepatic encephalopathy:
coagulopathy: anaemia and ascites.
Monitoring: premedication. induction and maintenace of
anaesthesia as well as intraoperative problems have been
discussed in details together with the surgical technigue of
liver transplantation.
the intraoperative problems encountered during liver
transplant operations are metabolic (biochemical) and
hemodynamic in nature.Intraoperative hypglycemia does not
present a problem. Cardiovascular changes are difficult to
manage before and after the anhepatic phase. and
hyperkalemic cardiac arrest at the time of revacularization
remains a major risk. Unintentional hypothermia and
decreased ionised calcium levels contributed to the
instability of cardiac rhythm and contractility. Massive
blood loss is the rule in all cases. Inspite of significant
preoperative coagulation factor deficits. the intraoperative
anhepatatic period. and massive blood losses. haemostasis is
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achieved with infusion of fresh frozen plasma and platelets
as indicated by prothrombin and partial thromboplastin
meBsurments andplatelet counts.
The most common hepatic complication in the postoperative
period is rejection of the graft liver.
It is also common to support ventilation of the lungs
via endotracheal tube for 24 to 48 hours after surgery as
hypoxaemia may develop due to postoperative hypoventilation.
Hypoventilation is due to large abdominal wound.
ab~ominal ditension. diaphragmatic dysfunction. reactive
pl,ural effusion. and vulnerability to infection in the
immunosuppressed patient.
Patient who receive immunosuppressive therapy may
develop bacterial infection or infection by fungus or
cytomegalovirus. Forty percent of mortality is associated
with infection. The primary site of which is
abdominalcavity.Changes in cardiovascular and renal
function: fluid and electrolyte imbalance as well as mental
confusion are also among the notable problems of
postoperative period.
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