Applicability of blunt renal trauma classification of Japanese Association for the Surgery of Trauma (JAST)

The Japanese Urological Association's clinical practice guidelines for urotrauma 2023

The Japanese Urological Association's guidelines for the treatment of renal trauma were published in 2016. In conjunction with its revision, herein, we present the new guidelines for overall urotrauma. Its purpose is to provide standard diagnostic and treatment recommendations for urotrauma, including iatrogenic trauma, to preserve organ function and minimize complications and fatality. The guidelines committee comprised urologists with experience in urotrauma care, selected by the Trauma and Emergency Medicine Subcommittee of the Specialty Area Committee of the Japanese Urological Association, and specialists recommended by the Japanese Association for the Surgery of Trauma and the Japanese Society of Interventional Radiology. The guidelines committee established the domains of renal and ureteral, bladder, urethral, and genital trauma, and determined the lead person for each domain. A total of 30 clinical questions (CQs) were established for all domains; 15 for renal and ureteral trauma and five each for the other domains. An extensive literature search was conducted for studies published between January 1, 1983 and July 16, 2020, based on the preset keywords for each CQ. Since only few randomized controlled trials or meta-analyses were found on urotrauma clinical practice, conducting a systematic review and summarizing the evidence proved challenging; hence, the grade of recommendation was determined according to the 2007 "Minds Handbook for Clinical Practice Guidelines" based on a consensus reached by the guidelines committee. We hope that these guidelines will be useful for clinicians in their daily practice, especially those involved in urotrauma care.

The American Association for the Surgery of Trauma renal injury grading scale: Implications of the 2018 revisions for injury reclassification and predicting bleeding interventions

BACKGROUND

In 2018, the American Association for the Surgery of Trauma (AAST) published revisions to the renal injury grading system to reflect the increased reliance on computed tomography scans and non-operative management of high-grade renal trauma (HGRT). We aimed to evaluate how these revisions will change the grading of HGRT and if it outperforms the original 1989 grading in predicting bleeding control interventions.

METHODS

Data on HGRT were collected from 14 Level-1 trauma centers from 2014 to 2017. Patients with initial computed tomography scans were included. Two radiologists reviewed the scans to regrade the injuries according to the 1989 and 2018 AAST grading systems. Descriptive statistics were used to assess grade reclassifications. Mixed-effect multivariable logistic regression was used to measure the predictive ability of each grading system. The areas under the curves were compared.

RESULTS

Of the 322 injuries included, 27.0% were upgraded, 3.4% were downgraded, and 69.5% remained unchanged. Of the injuries graded as III or lower using the 1989 AAST, 33.5% were upgraded to grade IV using the 2018 AAST. Of the grade V injuries, 58.8% were downgraded using the 2018 AAST. There was no statistically significant difference in the overall areas under the curves between the 2018 and 1989 AAST grading system for predicting bleeding interventions (0.72 vs. 0.68, p = 0.34).

CONCLUSION

About one third of the injuries previously classified as grade III will be upgraded to grade IV using the 2018 AAST, which adds to the heterogeneity of grade IV injuries. Although the 2018 AAST grading provides more anatomic details on injury patterns and includes important radiologic findings, it did not outperform the 1989 AAST grading in predicting bleeding interventions.

LEVEL OF EVIDENCE

Prognostic and Epidemiological Study, level III.

Incidence of urinary extravasation and rate of ureteral stenting after high-grade renal trauma in adults: a meta-analysis

Background

Collecting system injury and urinary extravasation is an important yet understudied aspect of renal trauma. We aimed to examine the incidence of urinary extravasation and also the rates of ureteral stenting after high-grade renal trauma (HGRT) in adults.

Methods

A search strategy was developed to search Ovid Medline, Embase, CINAHL, and Cochrane Library. Two reviewers screened titles and abstracts, followed by full-text review of the relevant publications. Studies were included if they indicated the number of patients with HGRT [the American Association for the Surgery of Trauma (AAST) grades III–IV or equivalents] and number of patients with urinary extravasation. A descriptive meta-analysis of binary proportions was performed with random-effects model to calculate the incidence of urinary extravasation and rates of ureteral stenting.

Results

After screening, 24 and 20 studies were included for calculating urinary extravasation and stenting rates, respectively. Most studies involved blunt injury and were retrospective single-center case series. Incidence of urinary extravasation was 29% (95% CI: 17–42%) after HGRT (grade III–V), and 51% (95% CI: 38–64%) when only grade IV–V injuries were combined. Overall, 29% (95% CI: 22–36%) of patients with urinary extravasation underwent ureteral stenting.

Conclusions

Approximately 30% of patients with HGRT are diagnosed with urinary extravasation and 29% of those with urinary extravasation undergo ureteral stenting. Understanding the rate of urinary extravasation and interventions is the first step in creating a prospective trial designed to demonstrate when ureteral stenting and aggressive management of urinary extravasation is needed.

PREDICTIVE FACTORS OF THE INITIAL TREATMENT FOR 207 BLUNT RENAL TRAUMA CASES BASED ON THE CLASSIFICATION FOR RENAL INJURY OF JAPANESE ASSOCIATION FOR THE SURGERY OF TRAUMA 2008's VERSION

(Objective) We retrospectively investigated the applicability of the Japanese Association for the Surgery of Trauma (JAST) classification version 2008 for renal injuries as predictive factors of the initial treatment for 207 blunt renal injury cases. (Materials and methods) We reviewed 207 patients between 1982 and 2013 who were admitted to our institution with blunt renal trauma. Patients were classified as conservative management group, immediate transcatheter arterial embolization (TAE) group, and immediate nephrectomy group by initial treatment. We retrospectively assessed several parameters including JAST criteria version 2008 type of renal injury (type), severity of hematoma (H factor) and extravasation of urine (U factor), the shock on arrival, associated abdominal injuries, serum hemoglobin levels, and macrohematuria as predicting factors of initial treatment of blunt renal trauma. (Result) TypeIII and PV injuries, H2 factor and associated non-renal abdominal injuries were predictive factors of immediate nephrectomy (p=0.001, p=0.000, p=0.003). TypeIII and PV injuries and H2 factor were predictive factors of immediate TAE. Both of H2 and U2 factors were significant predictors of immediate nephrectomy in patients with typeIII injury. H factor was a significantly predictive factor of immediate TAE in patients with typeI/II injuries (p=0.040). The rate of immediate TAE has been increasing but the rate of partial nephrectomy except for nephrectomy has been decreasing since the year 2007 when TAE was immediately available in our hospital. (Conclusion) The type category and severity of hematoma of JAST classification version 2008 would be predictive factors of initial management of blunt renal injuries. Patients with typeIII injuries and both of H2 and U2 factors, can be adapted to immediate nephrectomy. Patients with typeI/II and H2 factors can be adapted to immediate TAE.

Experience of renal artery embolization in patients with blunt kidney trauma

Introduction

The ren is considered as the most commonly damaged genitourinary organ. In general, blunt kidney traumas (BKT) are mild and can be managed conservatively. We aimed to analyze our own experiences of selective renal artery embolization (RAE) in BKT patients and compare obtained results with other reports.

Material and methods

We analyzed the medical and technical outcomes of RAE in 20 patients with grades II-IV blunt kidney traumas. Indications for RAE were blunt kidney trauma combined with a gross hematuria that could not be stopped conservatively. For evaluating the functioning of kidneys we used radioisotope renography.

Results

According to the American Association for the Surgery of Trauma classification, grade II blunt kidney injury was registered at 2 (10.0%) pts, grade III – at 11 (55.0%) pts and grade IV – at 7 (35.0%) pts. In all patients, the bleeding was stopped with the embolization procedure. 18 (90.0%) patients were treated in a single interventional session and 2 (10.0%) needed further intervention. Different complications were registered as 5 (25%) pts: two or more complications were often combined in each individual case. The function in damaged kidneys was preserved at the 3^rd month after RAE sessions.

Conclusions

RAE is an effective, minimally invasive treatment for blunt kidney injury that ensures the cessation of gross hematuria and kidney function preserving.

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.