Case Id: JSSMCRADC0059
The liver is one of the most frequently damaged organs in blunt trauma, and liver trauma is associated with a significant mortality rate.
In blunt abdominal trauma, the liver is injured ~5% (range 1-10%) of the time.
Patients can present with right upper quadrant pain, right shoulder tip pain (from diaphragmatic irritation), hypotension and shock .
The mechanism for liver trauma can be from blunt (e.g. motor vehicle collision, fall, direct blow, etc.) or penetrating trauma (e.g. gunshort, stabbing).
Most (~80%) of liver injuries are minor (grades I to III). There is a range of injuries:
- laceration (most common)
- haematoma - subcapsular or intraparenchymal
- active haemorrhage
- major hepatic vein injury
- AV fistula
Approximately 80% of the liver injuries are associated with other abdominal injuries
- liver lacerations that extend to the bare area can be associated with a retroperitoneal hematoma or an adrenal hemorrhage
- liver lacerations that extend to the porta hepatis can be associated with bile duct injuries
- right lower lobe pulmonary contusion/laceration
- right sided rib fractures
- Pneumo /hemothorax
- Right kidney injury
Elevated liver transaminases (ALT/AST) is 100% specific and ~93% sensitive in predicting liver injuries .
CT is the investigation of choice for evaluating for liver trauma. It is ~95% sensitive and 99% specific for detecting liver injuries.
- Lacerations appear as irregular linear/branching areas of hypoattenuation
- Haematomas appear as a hypodensity between the liver and its capsule (and can be differentiated from intra-peritoneal haematoma as these distort the liver architecture) or can be intraparenchymal
- Acute haematomas/haemorrhage are typically hyperdense (40-60HU) compared to normal liver parenchyma
AAST liver injury scale
The AAST (American Association for the Surgery of Trauma) liver injury scale 1994 revision is the most widely used liver injury grading system at the time of writing (mid 2016).
- grade I
- haematoma: subcapsular, <10% surface area
- laceration: capsular tear, <1 cm parenchymal depth
- grade II
- haematoma: subcapsular, 10-50% surface area
- haematoma: intraparenchymal <10 cm diameter
- laceration: capsular tear 1-3 cm parenchymal depth, <10 cm length
- grade III
- haematoma: subcapsular, >50% surface area of ruptured subcapsular or parenchymal haematoma
- haematoma: intraparenchymal >10 cm or expanding
- laceration: capsular tear >3 cm parenchymal depth
- grade IV
- laceration: parenchymal disruption involving 25-75% hepatic lobe or involves 1-3 Couinaud segments
- grade V
- laceration: parenchymal disruption involving >75% of hepatic lobe or involves >3 Couinaud segments (within one lobe)
- vascular: juxtahepatic venous injuries (retrohepatic vena cava / central major hepatic veins)
- grade VI
- vascular: hepatic avulsion
PS:Advance one grade for multiple injuries up to grade III
Treatment and prognosis
Most (>80%) of liver injuries can be treated non-surgically, and in blunt trauma relies on haemodynamic stability rather than a grade of injury. There is a significant mortality rate of ~8% (range 4.1-11.7%) associated with liver trauma . Complications are reported in ~20% of cases of non-operatively treated liver trauma :
- Bile duct injury leading to bile peritonitis or biloma
- delayed haemorrhage
- intra-abdominal abscess formation
- Acute acalculous cholecystitis