Category: Trauma
Keywords: kidney trauma, grading, (PubMed Search)
Posted: 3/16/2025 by Robert Flint, MD
(Updated: 3/21/2025)
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Unless a patient is unstable, renal injuries are managed non-operatively or endovascularly. Here is the
2025 Kidney Injury Grading Scale from AAST.
AAST AIS
Grade Severity Imaging Criteria
I 2 –Subcapsular hematoma <3.5 cm without active bleeding
– Parenchymal contusion without laceration
II 2 – Parenchymal laceration length <2.5 cm
– HRD <3.5 cm without active bleeding
III 3 – Parenchymal laceration length ?2.5 cm
– HRD ?3.5 cm without active bleeding
– Partial kidney infarction
– Vascular injuries without active bleeding
– Laceration extending into urinary collecting system and/or urinary extravasation
IV 4 – Active bleeding from kidney
– Pararenal extension of hematoma
– Complete/near-complete kidney infarction without active bleeding
– MFK without active bleeding
– Complete/near-complete ureteropelvic junction disruption
V 5 – Main renal artery or vein laceration or transection with active bleeding
– Complete/near-complete kidney infarction with active bleeding
– MFK with active bleeding
Keihani, Sorena MD, MSCI; Tominaga, Gail T. MD; Matta, Rano MD; Gross, Joel A. MD; Cribari, Chris
MD; Kaups, Krista L. MD, MSc; Crandall, Marie MD, MPH, FACS; Kozar, Rosemary A. MD; Werner,
Nicole L. MD, MS; Zarzaur, Ben L. MD; Coburn, Michael MD, FACS; Myers, Jeremy B. MD, FACS. Kidney
organ injury scaling: 2025 update. Journal of Trauma and Acute Care Surgery 98(3):p 448-451, March
2025. | DOI: 10.1097/TA.0000000000004509
