Surgical Anatomy of the liver
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The anatomical right and left hemilivers are separated
by an imaginary line running from the medial aspect of
the gallbladder fossa to the inferior vena cava, running
parallel with the fissure of the round ligament. This
division is known as the Cantlie line marks the course of
the middle hepatic vein. The right hepatic vein further
subdivides the right liver into anterior (segments V and
VIII) and posterior (segments VI and VII) sectors, while
the umbilical fissure subdivides the left liver into the
medial sector (segment IV) and left lateral segment
(segments II and III)
LIVER TRAUMA
The liver is the second most common organ injured in
abdominal trauma Liver trauma can be divided into blunt
and penetrating injuries.
Blunt injury produces contusion, laceration and avulsion
injuries to the liver. Penetrating injuries, are due to stab and
gunshot wounds, are often associated with chest or
pericardial involvement. Blunt injuries are more common
and have a higher mortality than penetrating injuries All
lower chest and upper abdominal stab wounds should be
suspect, especially if considerable blood volume
replacement has been required. Similarly, severe crushing
injuries to the lower chest or upper abdomen often combine
rib fractures, haemothorax and damage to the spleen and/or
liver. Focused assessment sonography in trauma (FAST)
performed in the emergency room can reliably diagnose free
.intraperitoneal fluid
injuries
Initial management of liver injuries in
Penetrating
Insert two large-bore cannulae and blood sent for crossmatch of ten
units of blood, full blood count, urea and electrolytes, liver function
tests, clotting screen, glucose and amylase.
Initial volume replacement should be with colloid or O-negative
blood if necessary. Arterial blood gases should be obtained .Intercostal
chest drains should be inserted if associated pneumothorax or
haemothorax is suspected. Once initial resuscitation has commenced,
the patient should be transferred to the operating theatre.
The fresh-frozen plasma and cryoprecipitate should be started and
clotting factors should be given empirically, aided by the results of
thromboelastography (TEG),.
A contrast CT prior to laparotomy should be considered if the patient
is haemodynamically stable.
Blunt trauma
With blunt injuries, the initial plan for resuscitation and management is
similar to penetrating injuries. Patients who are haemodynamically unstable
will require an immediate laparotomy. For the patient who is
haemodynamically stable,
Imaging by CT should be performed to further evaluate the nature of the
injury . Most patients with blunt liver injury who are haemodynamically
stable can be managed conservatively.
The indication for discontinuing conservative treatment for blunt liver
trauma would be: development of haemodynamically instability, evidence of
ongoing blood loss despite correction of any underlying coagulopathy and
the development of signs of generalised peritonitis. Interventional radiology
is vital , especially in embolisation to control hepatic artery bleeding in a
stable patient with no evidence of hollow viscus perforation
.
The surgical approach to liver trauma
Good access is vital. A ‘rooftop’ incision with midline extension
to the xiphisternum and retraction of the costal margins gives
excellent access to the liver and spleen Compression of the liver with
packs and correction of coagulopathy, if present, will control most of
active bleeding. From the right side of hepatoduodenal l igament and
deep (dorsal) to the porta hepatis is the foramen of Winslow, also
known as the epiploic foramen. If bleeding persists, further control
can be achieved by vascular inflow occlusion by placing an atraumatic
clamp across the foramen of Winslow (the Pringle manoeuvre).
A stab incision in the liver can be sutured with a fine absorbable
monofilament suture. Lacerations to the hepatic artery should be
identified an repaired with 6/0 Prolene suture.
Features of chronic liver disease
Lethargy Fever Jaundice Protein catabolism (wasting)
Coagulopathy (bruising) Cardiac (hyperdynamic circulation)
Neurological (hepatic encephalopathy) Portal hypertension
Ascite Oesophageal varices Splenomegaly Cutaneous
Spider naevi Palmar erythema
Portal hypertension; direct portal venous pressure that is >5
mmHg greater than the inferior vena cava (IVC) pressure, a
splenic pressure of >15 mmHg, or a portal venous pressure
measured at surgery of >20 mmHg is abnormal and indicates
portal hypertension.