Management trends, angioembolization performance and multiorgan injury indicators of renal trauma from Japanese administrative claims database

Objectives: To show the characteristics and therapeutic trends of renal trauma in Japan using a nationwide database. Methods: All renal trauma cases from the Diagnosis Procedure Combination database during 6 months of each year from 2006 to 2008 were included in the analysis. The following variables were considered: demographics, ambulance use, comorbid trauma, interventions, mechanism of injury and the Abbreviated Injury Scale. Patients were divided into two groups by trauma range: limited to rib, abdomen and pelvis (group A) or more extended (including supradiaphragmatic regions or lower extremities; group B). Rib fracture impact was assessed as a predictor of comorbid organ trauma. The incidences of angioembolization failure and nephrectomy were also evaluated. Results: A total of 1505 renal trauma cases (1014 and 491 in groups A and B, respectively) were identified. Comorbid trauma in the liver, spleen and lumbar/pelvic fractures were 7.4%, 5.6% and 5.1% in group A and 24.0%, 11.2% and 17.5% in group B, respectively. The rates of angioembolization (and its failure proportion), nephrectomy, transfusion and mortality were 7.9% (12.5%), 3.3%, 15.6% and 1.1% in group A, and 17.1% (11.9%), 2.6%, 28.3% and 8.1% in group B, respectively. Risks of coincident traumas in the liver, spleen and pelvic fracture were 2.23, 2.35 and 2.72 times higher if a rib fracture was observed. The incidences of renal trauma and nephrectomy (per 100 000 person-years) were estimated as 2.06 and 0.063, respectively. Conclusions: Angioembolization failure is not rare, and nephrectomy is an important last resort. Patients with comorbid rib fracture should be explored for coincident traumas.