Should blunt segmental vascular renal injuries be considered an American Association for the Surgery of Trauma Grade 4 renal injury?
BACKGROUND
Renal segmental vascular injury (SVI) following blunt abdominal trauma is not part of the original American Association for the Surgery of Trauma (AAST) renal injury grading system. Recent recommendations support classifying SVI as an AAST Grade 4 (G4) injury. Our primary aim was to compare outcomes following blunt renal SVI and blunt renal collecting system lacerations (CSLs). We hypothesize that renal SVI fare well with conservative management alone and should be relegated a less severe renal AAST grade.


METHODS
We retrospectively identified patients with SVI and G4 CSL admitted to a Level 1 trauma center between 2003 and 2010. Penetrating trauma was excluded. Need for surgical intervention, length of stay, kidney salvage (>25% renal preservation on renography 6-12 weeks after injury), and delayed complication rates were compared between the SVI and CSL injuries. Statistical analysis used χ, Fisher's exact, and t tests.


RESULTS
A total of 56 patients with SVI and 88 patients with G4 CSL sustained blunt trauma. Age, Injury Severity Score (ISS), and length of stay were similar for the two groups. Five patients in each group died of concomitant, nonrenal injuries. In the G4 CSL group, 15 patients underwent major interventions, and 32 patients underwent minor interventions. Only one patient in the SVI group underwent a major intervention. The renal salvage rate was 85.7% following SVI versus 62.5% following CSL (p = 0.107).


CONCLUSIONS
Overall, surgical interventions are significantly lower among the SVI cohort than the G4 CSL cohort. Further analysis using a larger cohort of patients is recommended before revising the current renal grading system. Adding SVI as a G4 injury could potentially increase the heterogeneity of G4 injuries and decrease the ability of the AAST renal injury grading system to predict outcomes, such as nephrectomy rate.


METHODS
Epidemiologic study, level IV.
From the Department of Urology (B.M., B.F., H.W., B.B.V.), University of Washington Medical Center; Harborview Injury Prevention and Research Center (H.W., B.B.V.), Seattle, Washington.
Bahaa
B
Malaeb
Brad
B
Figler
Hunter
H
Wessells
Bryan B
BB
Voelzke
D000007:Abdominal Injuries / Q000145:classification* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000792:Angiography / Q000379:methods; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D015601:Injury Severity Score; D007668:Kidney / Q000098:blood supply / Q000293:injuries*; D007685:Kidney Tubules, Collecting / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D022125:Lacerations / Q000145:classification / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012955:Societies, Medical; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed / Q000379:methods; D014193:Trauma Centers; D016896:Treatment Outcome; D057772:Vascular System Injuries / Q000145:classification* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D014949:Wounds, Nonpenetrating / Q000145:classification* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D055815:Young Adult