Purpose: To better characterize traumatic renal injury a revision to the 1989 American Association for the Surgery of Trauma renal injury scale was proposed in which grade IV includes all collecting system and segmental vascular injuries and grade V includes main renal hilar injury. We sought to validate the 2009 grading scale, emphasizing reclassifications between the 1989 and 2009 versions, and subsequent management.
Materials and methods: Patient demographics and renal injury characteristics, computerized tomography imaging, radiology reports and subsequent management were recorded in a prospective trauma database. Multivariable logistic regression models for intervention were compared using 1989 and 2009 grades to evaluate which grading scale better predicted management.
Results: Of 256 renal injury cases 56 (21.9%) were reclassified using the revised 2009 scale, including 50 (19.5%) which were upgraded, 6 (2.3%) which were downgraded and 200 (78.1%) which were unchanged. Of grade III or higher cases management was nonoperative in 112 (78.9%), angioembolization in 9 (6.3%), nephrectomy in 9 (6.3%) and renorrhaphy in 12 (8.5%). Management was significantly associated with original and revised grades (chi-square p=0.02 and <0.001, respectively). Further, the multivariable model using the 2009 grades significantly outperformed the 1989 model. Radiology reports rarely included renal injury scales.
Conclusions: Using the revised renal injury grading scale led to more definitive classification of renal injury and a stronger association with renal trauma management. Applying the revised criteria may facilitate and improve the multidisciplinary care of renal trauma.
Keywords: clinical decision-making; kidney; tomography; trauma severity indices; wounds and injuries; x-ray computed.