Editing Liver injury (section)

== Grading ==

* Most blunt trauma leads to low-grade injuries, since higher-grade injuries are big lacerations
* Grade IV and V injuries are really rare, like 0.1% of liver trauma

{| class="wikitable"
|AAST Grade
|'''Imaging Criteria (CT Findings)'''
|Operative Criteria
|Pathologic Criteria
|-
|I
|'''Subcapsular hematoma <10% surface area''' 
|Subcapsular hematoma <10% surface area 
|Subcapsular hematoma <10% surface area 
|-
|
|'''Parenchymal laceration <1 cm depth'''
|Parenchymal laceration <1 cm depth
|Parenchymal laceration <1 cm depth
|-
|
| 
|Capsular tear 
|Capsular tear 
|-
|II
|'''Subcapsular hematoma 10-50% surface area; intraparenchymal hematoma <10 cm in diameter'''
|Subcapsular hematoma 10-50% surface area; intraparenchymal hematoma <10 cm in diameter
|Subcapsular hematoma 10-50% surface

area; intraparenchymal hematoma

<10 cm in diameter
|-
|
|'''Laceration 1-3 cm in depth and'''

'''≤10 cm length'''
|Laceration 1-3 cm in depth and

≤10 cm length
|Laceration 1-3 cm in depth and

≤10 cm length
|-
|III 
|'''Subcapsular hematoma >50% surface area;'''

'''ruptured subcapsular or parenchymal'''

'''hematoma''' 
|Subcapsular hematoma >50% surface area or

expanding; ruptured subcapsular or

parenchymal hematoma
|Subcapsular hematoma >50% surface area;

ruptured subcapsular or intraparenchymal

hematoma 
|-
|
|'''Intraparenchymal laceration >10 cm'''
|Intraparenchymal hematoma >10 cm
|Intraparenchymal hematoma >10 cm
|-
|
|'''Laceration >3 cm depth'''
|Laceration >3 cm depth
|Laceration >3 cm depth
|-
|
|'''Any injury in the presence of a liver'''

'''vascular injury or active bleeding'''

'''contained within liver parenchyma'''
|
|
|-
|IV
|'''Parenchymal disruption involving'''

'''25-75% of a hepatic lobe'''
|Parenchymal disruption involving

25-75% of a hepatic lobe
|Parenchymal disruption involving

25-75% of a hepatic lobe
|-
|
|'''Active bleeding extending beyond the'''

'''liver parenchyma into the peritoneum'''
|
|
|-
|V
|'''Parenchymal disruption >75% of hepatic lobe'''
|Parenchymal disruption >75% of hepatic lobe
|Parenchymal disruption >75% of hepatic lobe
|-
|
|'''Juxtahepatic venous injury to include'''

'''retrohepatic vena cava and central'''

'''major hepatic veins'''
|Juxtahepatic venous injury to include

retrohepatic vena cava and central

major hepatic veins
|Juxtahepatic venous injury to include

retrohepatic vena cava and central

major hepatic veins
|}
''Vascular injury is defined as a pseudoaneurysm or arteriovenous fistula and appears as a focal collection of vascular contrast that decreases in attenuation with delayed imaging. Active bleeding from a vascular injury presents as vascular contrast, focal or diffuse, that increases in size or attenuation in delayed phase. Vascular thrombosis can lead to organ infarction.''

''Grade based on highest grade assessment made on imaging, at operation or on pathologic specimen.''

''More than one grade of liver injury may be present and should be classified by the higher grade of injury.''

''Advance one grade for multiple injuries up to grade III.''