American Association for the Surgery of Trauma Organ Injury Scale I: spleen, liver, and kidney, validation based on the National Trauma Data Bank.

BACKGROUND This study attempts to validate the American Association for the Surgery of Trauma (AAST) Organ Injury Scale (OIS) for spleen, liver, and kidney injuries using the National Trauma Data Bank (NTDB). STUDY DESIGN All NTDB entries with Abbreviated Injury Scale codes for spleen, liver, and kidney were classified by OIS grade. Injuries were stratified either as an isolated intraabdominal organ injury or in combination with other abdominal injuries. Isolated abdominal solid organ injuries were additionally stratified by presence of severe head injury and survival past 24 hours. The patients in each grading category were analyzed for mortality, operative rate, hospital length of stay, ICU length of stay, and charges incurred. RESULTS There were 54,148 NTDB entries (2.7%) with Abbreviated Injury Scale-coded injuries to the spleen, liver, or kidney. In 35,897, this was an isolated abdominal solid organ injury. For patients in which the solid organ in question was not the sole abdominal injury, a statistically significant increase (p < or = 0.05) in mortality, organ-specific operative rate, and hospital charges was associated with increasing OIS grade; the exception was grade VI hepatic injuries. Hospital and ICU lengths of stay did not show substantial increase with increasing OIS grade. When isolated organ injuries were examined, there were statistically significant increases (p < or = 0.05) in all outcomes variables corresponding with increasing OIS grade. Severe head injury appears to influence mortality, but none of the other outcomes variables. Patients with other intraabdominal injuries had comparable quantitative outcomes results with the isolated abdominal organ injury groups for all OIS grades. CONCLUSIONS This study validates and quantifies outcomes reflective of increasing injury severity associated with increasing OIS grades for specific solid organ injuries alone, and in combination with other abdominal injuries.