AAST Liver Trauma Classification [9].

Table 1: AAST Liver Trauma Classification [9].

Grade	Injury type	Injury description
I	Haematoma	Subcapsular < 10% surface
I	Laceration	Capsular tear < 1 cm parenchymal depth
II	Haematoma	Subcapsular 10-50% surface area; intraparenchymal, < 10 cm diameter
II	Laceration	1-3 cm parenchymal depth, < 10 cm in length
III	Haematoma	Subcapsular > 50% surface area or expanding, ruptured subcapsular or parenchymal haematoma. Intraparenchymal haematoma > 10 cm
III	Laceration	> 3 cm parenchymal depth
IV	Laceration	Parenchymal disruption 25-75% of hepatic lobe
IV	Vascular	Juxtavenous hepatic injuries i.e. retrohepatic vena cava/central major hepatic veins
V	Vascular	Hepatic avulsion

Advance one grade for multiple injuries up to grade III. AAST liver injury scale (1994 revision).