Q: There are how many grades of liver injury?
According to American Association for the Surgery of Trauma (AAST) classification system, there are 6 levels of hepatic injury from subcapsular hematoma less than 10 percent surface area (grade 1) to hepatic avulsion (Grade 6) - Please refer to references for detailed grading.
Clinical significance: The likelihood of success with nonoperative management, is higher for Grade I, II and III, when compared to higher grades, like patients with hepatic avulsion definitely requires surgical intervention.
1. Moore EE, Cogbill TH, Jurkovich GJ, et al. Organ injury scaling: spleen and liver (1994 revision). J Trauma 1995; 38:323.
2. Tinkoff G, Esposito TJ, Reed J, et al. American Association for the Surgery of Trauma Organ Injury Scale I: spleen, liver, and kidney, validation based on the National Trauma Data Bank. J Am Coll Surg 2008; 207:646.