Perinephric Hematoma Size is Independently Associated with the Need for Urological Intervention in Multisystem Blunt Renal Trauma

Does a collecting system injury with grade iv renal blunt trauma always need urinary intervention?

PURPOSE

This study aimed to identify the characteristics associated with the need for urinary intervention for a blunt renal injury with collection system involvement using a computed tomography (CT) protocol for trauma.

MATERIALS AND METHODS

Abdominal CT images of patients with blunt renal injuries from 2016 to 2020 were reviewed. Patients with low-grade renal trauma, non-collecting system involvement, American Association for the Surgery of Trauma grade V shattered kidney, and emergent nephrectomy were excluded. The largest perinephric mass thickness was measured in the axial view using CT, and a cutoff value was obtained using a receiver-operating characteristic curve analysis. Risk factors for further urinary intervention were analyzed.

RESULTS

Among the 70 patients included in this study, those with perinephric mass thicknesses < 25 mm (n = 36) had a significantly lower rate of urinary intervention than those with perinephric mass thicknesses ≥ 25 mm (0 vs. 5; p = 0.023). There was no significant difference in the follow-up durations of the groups (19 days vs. 38 days; p = 0.198). More than 90% of the perinephric mass in the < 25 mm group resolved within a median follow-up duration of 38 days, whereas nearly half of the ≥ 25 mm group had a residual perinephric mass during a median follow-up duration of 19 days.

CONCLUSION

The initial CT protocol for trauma was useful for predicting the need for further urinary interventions for collecting system injuries. A perinephric mass thickness < 25 mm is predictive of a low likelihood of requiring urinary intervention.

Shattered Kidney After Renal Trauma: Should It Be Classified As an American Association for the Surgery of Trauma Grade V Injury?

OBJECTIVE

To study the prevalence and management of shattered kidney and to evaluate if the new description of "loss of identifiable renal anatomy" in the 2018 American Association for the Surgery of Trauma (AAST) organ injury scale (OIS) would improve the ability to predict bleeding control interventions.

METHODS

We used high-grade renal trauma data from 21 Level-1 trauma centers from 2013 to 2018. Initial CT scans were reviewed to identify shattered kidneys, defined as a kidney having ≥3 parenchymal fragments displaced by blood or fluid on cross-sectional imaging. We further categorized patients with shattered kidney in two models based on loss of identifiable renal parenchymal anatomy and presence or absence of vascular contrast extravasation (VCE). Bleeding interventions were compared between the groups.

RESULTS

From 861 high-grade renal trauma patients, 41 (4.8%) had shattered kidney injury. 25 (61%) underwent a bleeding control intervention including 18 (43.9%) nephrectomies and 11 (26.8%) angioembolizations. 18 (41%) had shattered kidney with "loss of identifiable parenchymal renal anatomy" per 2018 AAST OIS (model-1). 28 (68.3%) had concurrent VCE (model-2). Model-2 had a statistically significant improvement in area under the curve over model-1 in predicting bleeding interventions (0.75 vs 0.72; P = .01).

CONCLUSION

Shattered kidney is associated with high rates of active bleeding, urinary extravasation, and interventions including nephrectomy. The definition of shattered kidney is vague and subjective and our definition might be simpler and more reproducible. Loss of identifiable renal anatomy per the 2018 AAST OIS did not provide better distinction for bleeding control interventions over presence of VCE.

Complications after Nephron-sparing Interventions for Renal Tumors: Imaging Findings and Management

The two primary nephron-sparing interventions for treating renal masses such as renal cell carcinoma are surgical partial nephrectomy (PN) and image-guided percutaneous thermal ablation. Nephron-sparing surgery, such as PN, has been the standard of care for treating many localized renal masses. Although uncommon, complications resulting from PN can range from asymptomatic and mild to symptomatic and life-threatening. These complications include vascular injuries such as hematoma, pseudoaneurysm, arteriovenous fistula, and/or renal ischemia; injury to the collecting system causing urinary leak; infection; and tumor recurrence. The incidence of complications after any nephron-sparing surgery depends on many factors, such as the proximity of the tumor to blood vessels or the collecting system, the skill or experience of the surgeon, and patient-specific factors. More recently, image-guided percutaneous renal ablation has emerged as a safe and effective treatment option for small renal tumors, with comparable oncologic outcomes to those of PN and a low incidence of major complications. Radiologists must be familiar with the imaging findings encountered after these surgical and image-guided procedures, especially those indicative of complications. The authors review cross-sectional imaging characteristics of complications after PN and image-guided thermal ablation of kidney tumors and highlight the respective management strategies, ranging from clinical observation to interventions such as angioembolization or repeat surgery. Work of the U.S. Government published under an exclusive license with the RSNA. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available in the Online Learning Center. See the invited commentary by Chung and Raman in this issue.

Is routine re-imaging for high-grade renal injury needed? Retrospective analysis of 1500 abdominal trauma patients from a tertiary care trauma center over 11 years

INTRODUCTION AND AIM

The AUA and EAU guidelines recommend re-imaging in high-grade renal trauma, regardless of the clinical findings. The aim of this study was to assess the impact of re-imaging on the overall management and outcomes in these patients.

METHODS

The trauma registry of our tertiary care Level-1 trauma center was reviewed from January 2007 till October 2018. Out of 1536 patients with abdominal trauma, 174 patients with isolated renal injury were identified. Renal injuries were classified based on the AAST classification. Variables retrieved were demographics, renal injury grade, presence of urinoma, repeated imaging findings, and intervention after initial and repeated imaging.

RESULTS

Low-grade injury was found in 78.7% (137/174) compared to 21.3% (37/174) with high-grade injury. The majority (n = 136) of low-grade patients were managed conservatively except one patient with Grade III injury required angioembolization after initial imaging. Of the high-grade patients, 31/37 were treated conservatively except 6/37 patients required surgical intervention after initial imaging. Following re-imaging, only one patient required surgical intervention in the form of insertion of a drainage tube for a hematoma, which was possibly infected. The existence of urinoma (5 patients) or hematoma (47 patients) was not associated with significantly higher rate of intervention (p values: 0.717 and 0.138, respectively). No significant association was noted between hematoma size and rate of intervention (p value = 0.055).

CONCLUSION

Re-imaging for high-grade renal injuries could be limited to the presence of urinary extravasation in initial imaging or the presence of clinical deterioration such as pain, fever or decrease in hemoglobin level.

[Renal Parenchyma Trauma and General Trauma Recommandations]

INTRODUCTION

Among trauma emergencies, kidney damage is uncommon. The urologist is frequently on the second line in the management of patients with multiple traumatic lesions. Knowledge of treatment is necessary to be able to integrate the different teams involved in an approach that is both vital in the context of damage control and functional with a concern for parenchymal preservation.

METHODS

A systematic review of the literature was carried out using the Medline database in order to identify the most relevant articles in English and French.

RESULTS

Kidney trauma occurs either by direct shock or by a deceleration mechanism. They are classified by severity according to the AAST classification. Management is mostly conservative by avoiding surgery and controlling bleeding by arterial embolization. Surveillance checks for complications occurrence in high-grade trauma. Traumatic dissection of the renal artery, with a poor functional prognosis requires a short delay before treatment.

CONCLUSION

The prognosis for trauma to the kidney, regardless of the grade, is currently good, with improvements of effective resuscitation and embolization in the event of bleeding.

Endovascular management of vascular renal injuries: outcomes and comparison between traumatic and iatrogenic settings

PURPOSE

To evaluate the efficacy of endovascular treatment for vascular renal injuries (VRIs) like bleeding, pseudoaneurysm and artero-venous fistula (AVF) and to compare patients with blunt trauma (T-VRIs) with those with iatrogenic damage (I-VRIs).

METHODS

We retrospectively assessed 49 renal artery embolizations performed to treat T-VRIs (26.5%) and I-VRIs (73.5%). Different embolic materials were used based on the type of lesion. Technical success was defined as the complete occlusion of target arteries with no further visualization of VRIs. Clinical success was defined if no recurrence was present and if renal function (difference between creatinine after and before treatment <0.5 mg/dl) was preserved after 1 month.

RESULTS

Angiography showed bleeding in 27 patients, pseudoaneurysm in 29 and an AVF in 6. Embolic agents used were coils in 39 procedures, coils with sponge in four and others in six. Technical success was 100% while clinical success was 85.7% due to seven patients with recurrence. The group I-VRIs showed a higher rate of clinical success than the group T-VRIs (94.4% vs 61.5%; p < 0.05). Moreover, the group I-VRIs had a higher incidence of pseudoaneurysms and AVFs compared with the group T-VRIs (69.4% vs 30.8% and 16.7% vs 0%; p < 0.05).

CONCLUSION

Endovascular treatment for VRIs showed satisfactory results and no patient had a worsening of renal function. I-VRIs had better clinical success and more frequently appeared as pseudoaneurysms compared to T-VRIs: probably iatrogenic injury is localized and pseudoaneurysm is easily identifiable and treatable with endovascular treatment.

Initial radiological findings associated with active bleeding control necessity and long term functional outcomes after isolated high grade blunt renal trauma

INTRODUCTION

To assess the predictors for conservative management failure and long term outcomes after isolated blunt high grade renal trauma (HGRT).

METHODS

 A retrospective analysis of patients with isolated blunt HGRT (renal trauma grade ≥ IV) was conducted. Patients' demographics, clinical presentation, laboratory and radiological investigations, and different lines of treatment were retrieved. The primary outcome was to assess the predictors of conservative treatment failure (need for active bleeding control e.g.: transarterial angioembolization (TAE) and/or surgical exploration). The secondary outcome was to assess the renal parenchymal volume (RPV) changes post HGRT in correlation with the different lines of management using CT-measured RPV. The difference in RPV ≥ 5% at follow up was considered significant.

RESULTS

The study included 63 patients, mean (SD) age was 35.1 (16.6) years. Conservative management was successful in 39 patients (62%), while the need for active bleeding control was required in 16 and 8 patients who underwent TAE and surgical exploration, respectively. Increased hematoma rim distance (HRD), laceration numbers > 3, parenchymal devascularization ≥ 25%, and presence of vascular contrast extravasation (VCE) were predictors for conservative treatment failure (P= 0.006, 0.02, 0.045 and 0.002, respectively). After a mean of 19 months follow up, patients were subclassified into 2 groups: patients with preserved RPV (28 patients) and patients with decreased RPV (29 patients). Renal parenchymal devascularization ≥ 25% was found a predictor for ipsilateral RPV decrease (P = 0.02).

CONCLUSION

Increased HRD, laceration numbers > 3, parenchymal devascularization ≥ 25%, and presence of VCE are findings that reflect the necessity for active bleeding interventions after isolated blunt HGRT. Parenchymal devascularization ≥ 25% is an independent factor for RPV deterioration. Neither the grade of renal trauma nor the type of treatment is a predictor for such deterioration.

Traumatic renal artery dissection: from imaging to management

Injury to the renal artery following blunt trauma is detected increasingly due to widespread and early use of multidetector computed tomography (CT), but optimal treatment remains controversial as no guidelines are available. This review illustrates the spectrum of imaging findings of traumatic renal artery dissection based on our experience, with the aim of understanding the physiopathology of ischaemic damage to the kidney, and the process of choosing the best therapeutic strategy (conservative, endovascular, surgical). Five main patterns of traumatic renal artery dissection are described: avulsion of renal hilum; dissection of the segmental renal branches; preocclusive main renal artery dissection; renal artery stenosis without flow limitation; thrombogenic renal artery intimal tear. In the polytrauma patient, management depends on various factors (haemodynamic status, associated lesions, time of diagnosis) rather than on the degree of renal artery stenosis. Non-operative management (NOM) is the preferred option in case of non-flow-limiting dissection of the renal artery and angio-embolisation is an important adjunct to NOM in cases of active bleeding. Embolisation of the renal artery stump may be the best option in cases of occlusive dissection, as catheter manipulation carries a high risk of vessel rupture. The therapeutic window for kidney revascularisation in cases of flow-limiting dissection of main renal artery may be variable. Endovascular stenting >4 h after trauma should be performed only if residual flow with preserved parenchymal perfusion is detected at angiography. Antiplatelet therapy administration is recommended in cases of stenting, but conditioned by the bleeding risk of the patient.

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.

A nomogram predicting the need for bleeding interventions after high-grade renal trauma: Results from the American Association for the Surgery of Trauma Multi-institutional Genito-Urinary Trauma Study (MiGUTS)

BACKGROUND

The management of high-grade renal trauma (HGRT) and the indications for intervention are not well defined. The American Association for the Surgery of Trauma (AAST) renal grading does not incorporate some important clinical and radiologic variables associated with increased risk of interventions. We aimed to use data from a multi-institutional contemporary cohort to develop a nomogram predicting risk of interventions for bleeding after HGRT.

METHODS

From 2014 to 2017, data on adult HGRT (AAST grades III-V) were collected from 14 level 1 trauma centers. Patients with both clinical and radiologic data were included. Data were gathered on demographics, injury characteristics, management, and outcomes. Clinical and radiologic parameters, obtained after trauma evaluation, were used to predict renal bleeding interventions. We developed a prediction model by applying backward model selection to a logistic regression model and built a nomogram using the selected model.

RESULTS

A total of 326 patients met the inclusion criteria. Mechanism of injury was blunt in 81%. Median age and injury severity score were 28 years and 22, respectively. Injuries were reported as AAST grades III (60%), IV (33%), and V (7%). Overall, 47 (14%) underwent interventions for bleeding control including 19 renal angioembolizations, 16 nephrectomies, and 12 other procedures. Of the variables included in the nomogram, a hematoma size of 12 cm contributed the most points, followed by penetrating trauma mechanism, vascular contrast extravasation, pararenal hematoma extension, concomitant injuries, and shock. The area under the receiver operating characteristic curve was 0.83 (95% confidence interval, 0.81-0.85).

CONCLUSION

We developed a nomogram that integrates multiple clinical and radiologic factors readily available upon assessment of patients with HGRT and can provide predicted probability for bleeding interventions. This nomogram may help in guiding appropriate management of HGRT and decreasing unnecessary interventions.

LEVEL OF EVIDENCE

Prognostic and epidemiological study, level III.

Kidney and uro-trauma: WSES-AAST guidelines

Renal and urogenital injuries occur in approximately 10-20% of abdominal trauma in adults and children. Optimal management should take into consideration the anatomic injury, the hemodynamic status, and the associated injuries. The management of urogenital trauma aims to restore homeostasis and normal physiology especially in pediatric patients where non-operative management is considered the gold standard. As with all traumatic conditions, the management of urogenital trauma should be multidisciplinary including urologists, interventional radiologists, and trauma surgeons, as well as emergency and ICU physicians. The aim of this paper is to present the World Society of Emergency Surgery (WSES) and the American Association for the Surgery of Trauma (AAST) kidney and urogenital trauma management guidelines.

Spontaneous renal hemorrhage: critical analysis of different lines of management in non-traumatic patients: a single tertiary center experience

PURPOSE

To assess clinical presentation and outcomes of different treatment strategies in cases of spontaneous renal hemorrhage (SRH).

METHODS

A retrospective analysis of patients with SRH between 2000 and 2018 was performed. Patients' demographics, clinical presentation, laboratory and radiological investigations, and different lines of treatment were retrieved. The primary outcome was to assess the predictors of the success of conservative treatment. The secondary outcome was to assess the long-term renal function outcome comparing serum creatinine, e GFF, and CT-assessed renal volume at last follow-up with baseline values.

RESULTS

The study included 42 (23 males and 19 women) patients with mean ± SD age was 48.1 ± 17.8 years. Conservative management was successful in 19 (46%) patients. Trans-arterial embolization (TAE) was performed in 13 patients (30%) to control active bleeding. Ten patients (25%) required surgical exploration and nephrectomy. Lower serum creatinine (P = 0.003), higher prothrombin concentration (P = 0.04), lower hematoma size (P = 0.02), and non-AML lesions (P = 0.03) were independent predictors of conservative management success. Unlike the TAE-treated group, serum creatinine increased significantly (P = 0.04) with a significant decrease in e-GFR (P = 0.02) and renal volume (P < 0.001) of affected kidneys at last follow-up after conservative treatment.

CONCLUSION

Although SRH is a life-threatening condition, conservative treatment is successful in a certain subset of patients. However, it is associated with significant deterioration of the affected kidney function as well as renal volume.

The American Association for the Surgery of Trauma Organ Injury Scale 2018 update for computed tomography-based grading of renal trauma: a primer for the emergency radiologist

The most widely used trauma injury grading system is the Organ Injury Scale (OIS) by the American Association for the Surgery of Trauma (AAST). The AAST OIS for renal trauma was revised in 2018 to reflect necessary updates based on decades of experience with computed tomography (CT)-based injury diagnosis and, specifically, to better incorporate vascular injuries, which were not comprehensively addressed in the original OIS. In this review article, we describe CT findings of the AAST OIS for the kidney according to the 2018 revision, with an emphasis on real-world application, and highlight important differences from the prior grading scheme. Routine use of this grading system allows for a standardized classification of the range of renal injuries to aid in management, adding value in the imaging care of trauma patients.

The associations between initial radiographic findings and interventions for renal hemorrhage after high-grade renal trauma: Results from the Multi-Institutional Genitourinary Trauma Study

BACKGROUND

Indications for intervention after high-grade renal trauma (HGRT) remain poorly defined. Certain radiographic findings can be used to guide the management of HGRT. We aimed to assess the associations between initial radiographic findings and interventions for hemorrhage after HGRT and to determine hematoma and laceration sizes predicting interventions.

METHODS

The Genitourinary Trauma Study is a multicenter study including HGRT patients from 14 Level I trauma centers from 2014 to 2017. Admission computed tomography scans were categorized based on multiple variables, including vascular contrast extravasation (VCE), hematoma rim distance (HRD), and size of the deepest laceration. Renal bleeding interventions included angioembolization, surgical packing, renorrhaphy, partial nephrectomy, and nephrectomy. Mixed-effect Poisson regression was used to assess the associations. Receiver operating characteristic analysis was used to define optimal cutoffs for HRD and laceration size.

RESULTS

In the 326 patients, injury mechanism was blunt in 81%. Forty-seven (14%) patients underwent 51 bleeding interventions, including 19 renal angioembolizations, 16 nephrectomies, and 16 other procedures. In univariable analysis, presence of VCE was associated with a 5.9-fold increase in risk of interventions, and each centimeter increase in HRD was associated with 30% increase in risk of bleeding interventions. An HRD of 3.5 cm or greater and renal laceration depth of 2.5 cm or greater were most predictive of interventions. In multivariable models, VCE and HRD were significantly associated with bleeding interventions.

CONCLUSION

Our findings support the importance of certain radiographic findings in prediction of bleeding interventions after HGRT. These factors can be used as adjuncts to renal injury grading to guide clinical decision making.

LEVEL OF EVIDENCE

Prognostic and Epidemiological Study, Level III and Therapeutic/Care Management, Level IV.

Contemporary management of renal trauma in Canada: A 10-year experience at a level 1 trauma centre

INTRODUCTION

Contemporary Canadian renal trauma data is lacking. Our objective is to describe 10-year outcomes of renal trauma at a Canadian level 1 trauma centre using a conservative approach.

METHODS

The Alberta Trauma Registry at the University of Alberta was used to identify renal trauma patients from October 2004 to December 2014. Hospital records and imaging were reviewed to identify clinic-radiographical factors, including patient age, gender, Injury Severity Score (ISS), American Association of the Surgery for Trauma (AAST) grade, computerized tomography (CT) findings, urological interventions, length of stay, transfusion and death rates. Descriptive statistics, Chi-square, and t-tests were used when appropriate.

RESULTS

A total of 368 renal trauma patients were identified. Mechanism of injury was blunt trauma in 89.1% of cases, mean age was 36.2 years, and mean ISS was 30.8 (±13.6). AAST grade distribution was 16.6% (Grade 1), 22.8% (Grade 2), 36.4% (Grade 3), 20.9% (Grade 4), and 3.3% (Grade 5). Overall, 9.5% (35) of patients required urological intervention for a total of 40 treatments, including ureteral stenting (3.0%), angioembolization (3.3%), percutaneous drainage (0.3%), or open intervention including nephrectomy (2.4%) and renorrhaphy (0.5%). No Grade 1 or 2 injuries required intervention, while 1.5%, 31.2%, and 75.0% of Grade 3, 4, and 5 injuries did, respectively. The overall renal salvage rate was 97.6%, which did not differ by mechanism of injury (p=0.25). Patients with penetrating trauma were more likely to require urological intervention (20.0% vs. 8.2%; p=0.04). Of the high-grade (III-V) renal injuries identified, 15.7% (35/223) required urological intervention, 4.9% (11) required open surgical intervention, and only 4.0% (9) of patients with high-grade renal injury required nephrectomy.

CONCLUSIONS

The trend towards conservative treatment of renal trauma in Canada appears well-supported even in a severely injured patient population, as over 90% of patients avoid urological intervention and only 3% require operative intervention resulting in renal salvage rates of 97.6%.

Autosomal dominant polycystic kidney disease and minimal trauma: medical review and case report

Background

Blunt abdominal trauma in the setting of polycystic kidney disease is still scantly described in the literature and management guidelines of such patients are not well-established.

Case presentation

The authors herein present a case of hypovolemic shock secondary to segmental renal artery bleed in a 75-year-old man with polycystic kidney disease after minimal blunt abdominal trauma, who underwent successful selective arterial embolization, and provide a thorough review of similar cases in the literature, while shedding the light on important considerations when dealing with such patients.

Conclusions

It is important to suspect renal injury in patients with pre-existing renal lesions irrespective of the mechanism of injury; and, vice-versa to suspect an underlying abnormality in patients with a clinical deterioration that’s out of proportion to the mechanism of injury.

Electronic supplementary material

The online version of this article (10.1186/s12873-018-0192-3) contains supplementary material, which is available to authorized users.