Liver

AAST liver injury scale 2018

Grade I	— Subcapsular hematoma <10% surface area — Parenchymal laceration <1 cm in depth
Grade II	— Subcapsular hematoma 10–50% surface area — Intraparenchymal hematoma <10 cm in diameter — Laceration 1–3 cmin depth and ≤ 10 cm length
Grade III	— Subcapsular hematoma >50% surface area; ruptured subcapsular or parenchymal hematoma — Intraparenchymal hematoma >10 cm — Laceration >3 cm depth — Any injury in the presence of a liver vascular injury or active bleeding contained within liver parenchyma
Grade IV	— Parenchymal disruption involving 25–75% of a hepatic lobe — Active bleeding extending beyond the liver parenchyma into the peritoneum
Grade V	— Parenchymal disruption >75% of hepatic lobe — Juxtahepatic venous injury to include retrohepatic vena cava and central major hepatic veins

Note: Advance one grade for multiple hepatic injuries up to grade III.