Complications of Renal Trauma

Traumatic renal vein pseudoaneurysm

Traumatic renal injury is infrequent, occurring in ∼1% to 3% of trauma cases, with major renal vein injury an even more rare traumatic entity. Conservative, operative, and endovascular management strategies have been infrequently reported in the literature. We report a patient with traumatic renal vein injury with pseudoaneurysm formation that was successfully treated with endovascular stenting.

Complications of Renal Trauma

Renal trauma is rare, and significant complications from renal trauma are generally rarer still occurring in less than 5% in modern series. Close follow-up of injured patients and scrupulous use of imaging, including computed tomography scan, arteriogram, or retro-grade pyelogram when appropriate, increase detection rates and establish the diagnosis in most patients. Treatment varies by etiology and may range from watchful waiting to percutaneous drainage to, in rare cases, nephrectomy.

The Literature Increasingly Supports Expectant (Conservative) Management of Renal Trauma — A Systematic Review

BACKGROUND

The perfect degree of operative intervention in renal trauma is unknown. However, expectant management for most blunt renal trauma is the standard of care, and nonoperative management is increasingly accepted for stab wounds. The best treatment of gunshot wounds and vascular injuries is still unclear; however, recent data indicates that a trial of nonoperative therapy may be warranted in those not exsanguinating from the kidney. Conservative management has many benefits, the greatest of which is decreasing the rate of iatrogenic nephrectomy. We have reviewed the world's literature to determine the level of support for expectant management of renal injury.

METHODS

The English language literature concerning renal trauma was identified with the assistance of Medline, and additional cited works not picked up in the initial search were obtained. One hundred and ten citations were ultimately reviewed dating back to 1947.

RESULTS

Most modern citations support at least a trial of expectant management for renal trauma patients not exsanguinating from the kidney, and without ureteral or renal pelvis injuries. The treatment of renovascular injuries has less consensus, but it appears that 'conservative' management by the application of nephrectomy is often the best approach, although renovascular repair may be attempted in rare cases.

CONCLUSION

Dozens of papers going back as far as 50 years seem to support the wider use of nonoperative therapy of renal injuries, although for unclear reasons, this approach is not yet universally accepted.

Surgical exploration of the injured kidney: current indications and techniques

When treating renal injuries, the goals of the urologic surgeon are preservation of maximal renal function with a minimal risk of complications. To meet these, accurate staging is essential. The combined use of clinical and radiologic findings, with intra-operative information where available, will enhance the practitioner's ability to detect, classify, and treat renal injuries appropriately. We discuss our current approach to renal trauma and current indications and techniques for surgical exploration of the injured kidney.

[Renal trauma: is open surgery still up to date?]

For several years conservative treatment of renal trauma has been increasing. Investigation of circulatory conditions, renal ultrasound, and CT scan are necessary for assessing the extent of renal injury by the exact classifications of the organ injury scale. Through close cooperation of all departments involved, especially intensive care, traumatology, general surgery, radiology, and urology, it should be possible to limit primarily operative open surgery to life-threatening renal bleeding (grade V). All other cases require a repeat diagnosis for control purposes after 2-4 days. Complications found then can for the most part be treated conservatively or by minimally invasive techniques. Thus, open operative intervention has been minimized in these cases too.

Outcome after major renovascular injuries: a Western trauma association multicenter report

BACKGROUND

Major renal vascular injuries are uncommon and are frequently associated with a poor outcome. In addition to renal dysfunction, posttraumatic renovascular hypertension may result, although the true incidence of this complication is unknown. The objective of this study was to describe the factors contributing to outcome after major renovascular trauma. We hypothesized that the highest percentage of renal salvage would be achieved by minimizing the time from injury to repair.

METHODS

This was a retrospective chart review over a 16-year period conducted at six university trauma centers of patients with American Association for the Surgery of Trauma grade IV/V renal injuries surviving longer than 24 hours. Postinjury renal function with poor outcome was defined as renal failure requiring dialysis, serum creatinine greater than or equal to 2 mg/dL, renal scan showing less than 25% function of the injured kidney, postinjury hypertension requiring treatment, or delayed nephrectomy. Data collected for analysis included demographics, mechanism of injury, presence of shock, presence of hematuria, associated injuries, type of renal injury (major artery, renal vein, segmental artery), type of repair (primary vascular repair, revascularization, observation, nephrectomy), time from injury to definitive renal surgery, and type of surgeon performing the operation (urologist, vascular surgeon, trauma surgeon).

RESULTS

Eighty-nine patients met inclusion criteria; 49% were injured from blunt mechanisms. Patients with blunt injuries were 2.29 times more likely to have a poor outcome compared with those with penetrating injuries. Similarly, the odds ratio of having a poor outcome with a grade V injury (n = 32) versus grade IV (n = 57) was 2.2 (p = 0.085). Arterial repairs had significantly worse outcomes than vein repairs (p = 0.005). Neither the time to definitive surgery nor the operating surgeon's specialty significantly affected outcome. Ten percent (nine patients) developed hypertension or renal failure postoperatively: three had immediate nephrectomies, four had arterial repairs with one intraoperative failure requiring nephrectomy, and two were observed. Of the 20 good outcomes for grade V injuries, 15 had immediate nephrectomy, 1 had a renal artery repair, 1 had a bypass graft, 1 underwent a partial nephrectomy, and 2 were observed.

CONCLUSION

Factors associated with a poor outcome following renovascular injuries include blunt trauma, the presence of a grade V injury, and an attempted arterial repair. Patients with blunt major vascular injuries (grade V) are likely to have associated major parenchymal disruption, which contributes to the poor function of the revascularized kidney. These patients may be best served by immediate nephrectomy, provided that there is a functioning contralateral kidney.

Use of ureteral stents in the management of major renal trauma with urinary extravasation: is there a role?

Five patients with major (Grade IV) renal trauma required ureteral stent placement to facilitate urinary drainage. Three of these patients had stents placed for recurrent gross hematuria with flank pain. All three had obstructing blood clots present at the time of stent placement. The fourth patient had a stent placed because of persistent extravasation at 2 weeks postinjury. The last patient was considered at risk for persistent urinary extravasation because of a partial ureteropelvic junction obstruction and had a ureteral stent placed as part of the initial management. All patients were followed radiographically for resolution of extravasation. Long-term clinical follow-up consisted of serum creatinine evaluation and blood pressure monitoring. Urinary extravasation resolved in all five patients, as determined by radiologic evaluation, at a mean of 8 days after stent placement. Ureteral stents were left indwelling an average of 4 weeks. No patient developed hypertension, and all serum creatinine values were normal at a mean 26 months' follow-up. No patient developed urinoma or abscess, and none required open surgical exploration. Ureteral stents may be used safely and effectively to treat persistent or recurrent urinary extravasation resulting from major blunt renal trauma in appropriately selected patients. In addition, ureteral stents may avoid the need for surgical exploration in patients with Grade IV renal trauma who develop recurrent gross hematuria, flank pain, and persistent or recurrent extravasation secondary to clot obstruction.

Traumatic renal artery occlusion: a 15-year review

BACKGROUND

To better define what constitutes appropriate treatment for traumatic renal artery occlusion, we report our 15-year experience in managing this injury.

METHODS

A retrospective chart review was performed to evaluate treatment outcomes and complications of 12 patients (13 injuries) who presented to our trauma centers with renal artery occlusion secondary to blunt injury.

RESULTS

Five of 12 patients underwent attempted surgical revascularization with a median warm ischemia time of 5 hours (range, 4.5-36 hours). Of these five patients, one required nephrectomy for inability to establish arterial flow, three demonstrated no function, and one had return to 9% differential function on postoperative renal scan. Seven patients did not have attempted revascularization, and none of them experienced immediate complications. Hypertension developed in three patients (43%) who required nephrectomy to control blood pressure at a mean of 5 months after injury (range, 3-7 months). Four patients remained asymptomatic and normotensive at a mean follow-up of 11 months (range, 4 weeks to 2.6 years).

CONCLUSION

Surgical revascularization for traumatic renal artery occlusion seldom results in a successful outcome. Patients who are observed must have close follow-up for hypertension.

Conservative management with percutaneous intervention of major blunt renal injuries

This retrospective study assessed the results of treatment of patients with renal trauma to determine the optimal management (conservative or surgical) for patients with grade III renal injuries. During the past 12 years 108 patients (including 43 children) with renal injuries were managed: 43 had grade I injuries (renal contusion), 33 had grade II (minor laceration), 31 had grade III (major laceration), and 1 had grade IV (pedicle injury). All patients with grades I and II injuries were successfully managed conservatively. The patient with renal pedicle injury underwent uneventful nephrectomy. Nineteen patients with grade III injuries (including 5 patients with shattered kidneys and 3 patients with polar avulsion) were managed conservatively, and 2 developed progressively enlarging urinomas that required percutaneous drainage with complete resolution. No patient in this group developed perinephric abscess or urinary fistulae, and no delayed nephrectomy was necessary. Long-term follow-up of 7 patients in this group, including 3 with shattered kidneys and 2 with polar avulsion, showed that none have developed hypertension. Twelve patients with grade III injuries were managed surgically. Six (50%) patients underwent total (4 patients) or partial (2 patients) nephrectomy. In 6 patients, the surgical intervention was only open drainage of the perinephric collection and/or parenchymal suturing. It was concluded that conservative management with timely percutaneous or endoscopic intervention in patients with major renal injuries results in minimal loss of renal tissue without significant late complications.

MRI and CT in blunt renal trauma: an update

In our experience, MRI is as effective as CT in correctly staging renal injury. The coronal and sagittal slice orientations of MRI are particularly helpful in determining the extent of the renal parenchymal damage. Both methods are accurate in finding perirenal hematomas, assessing the viability of renal fragments, and detecting preexisting renal abnormalities but are relatively inaccurate in visualizing urinary extravasation. Although CT remains the method of choice in radiological staging of renal injury, MRI can complement CT in patients with severe renal injury, preexisting renal abnormality, equivocal CT findings, or when repeated radiological follow-up is required. MRI could replace CT in patients with iodine allergy and be used for initial staging if CT is not available.

Nonoperative Management of Solid Abdominal Visceral Injury: Part II. Liver and Kidney

Only in recent years has it been recognized that the injured liver is not only capable of spontaneous hemostasis, but also that it can heal itself remarkably well without surgical intervention. Currently, the approach to stable patients with blunt liver trauma should be nonoperative, regardless of the age of the patient, the degree of liver injury, or the amount of blood in the peritoneal cavity. However, success with this method of management is highly dependent on selection of patients whose liver has ceased bleeding and who do not have an associated intra-abdominal injury in need of operative repair. Similarly, a nonoperative approach is appropriate in patients with blunt renal trauma if the injury is properly staged and if major urinary extravasation and vascular injuries are not present.

Conservative treatment of an injured hydronephrotic kidney: the role of percutaneous nephrostomy

The authors report a child who presented with massive hematuria after blunt trauma to a hydronephrotic kidney (ureteropelvic junction stenosis). The insertion of a nephrostomy tube effectively decompressed the injured kidney and enabled an early reconstructive repair of the stenosed ureteropelvic junction.

Scarring following renal trauma in children

OBJECTIVE

To assess factors relating to renal scarring following kidney injury.

PATIENTS AND METHODS

A total of 25 children who had documented renal injury between 1981 and 1988 were included in the study and 19 were followed up for 1 month to 12 years (mean 5.5 years) and the development of hypertension and renal scars assessed using ultrasonography and radionuclide scans (dimercapto-succinic acid, DMSA).

RESULTS

Of the 19 children 13 had renal contusions, four had renal lacerations and two sustained severe renal injury, one of whom had pelvi-ureteric disruption. Eighteen patients presented with macroscopic or microscopic haematuria except the patient with pelvi-ureteric junction disruption who presented 3 weeks later with abdominal distension, vomiting and hypertension. All the patients were managed without an operation except the latter patient who required nephrectomy. Renal scarring was demonstrated in four children at a mean follow-up of 3.5 years, one following renal contusion (5% scarring), two after renal laceration (50% scarring) and one after rupture of the kidney (100% scarring). In one patient intravenous pyelography did not reveal a renal scar but a radionuclide scan performed 5 years later demonstrated a scar. Transient hypertension was noted in only two patients but peripheral plasma renin levels were normal.

CONCLUSION

Renal scars developed in four of 19 patients with renal trauma and more than half of the patients with severe renal injury. Long-term follow-up including a radionuclide scan is therefore necessary in patients with renal injury. Although no sustained hypertension was noted in any patients in this study, long-term blood pressure assessments would seem prudent.

Comparison of high-field magnetic resonance imaging with computed tomography in the evaluation of blunt renal trauma

OBJECTIVE

To compare magnetic resonance (MR) imaging and computed tomography (CT) in radiographic staging of blunt renal trauma.

DESIGN

A prospective study.

MATERIALS AND METHODS

Fourteen patients with blunt renal trauma not requiring early surgical treatment underwent CT, and high-field (1.0 T) MR imaging.

MEASUREMENTS AND MAIN RESULTS

MR imaging equaled CT in correctly grading the renal injury. The coronal and sagittal projections of MR imaging were helpful in determining the extent of the renal parenchymal lesion. Both methods were accurate in finding perirenal hematomas, assessing the viability of renal fragments, and detecting pre-existing renal abnormalities, but failed to visualize urinary extravasation on initial examination.

CONCLUSIONS

Although CT remains the method of choice in radiographic staging of renal injury, MR imaging can complement CT in patients with severe renal injury, pre-existing renal abnormality, equivocal CT findings, or when repeated radiographic follow-up is required. MR imaging could replace CT in patients with iodine allergy and be used for initial staging if CT is not available.

Blunt renal trauma in children: healing of renal injuries and recommendations for imaging follow-up

Initial CT grading of renal injury was correlated with the frequency of complications and the time course of healing in 35 children. All renal contusions (grade 1, 8) and small parenchymal lacerations (grade 2, 8) healed without complications. All lacerations extending to the collecting system (grade 3, 9) resulted in mild to severe loss of renal function with progressive healing over 4 months. One of four segmental infarcts (grade 4A), and five of six vascular pedicle injuries (grade 4B) resulted in severe loss of renal function. Complications, including urinoma (2), sepsis (1), hydronephrosis (1), and persistent hypertension (2), were limited to grade 3 and 4 injuries. Our results suggest that mild renal injuries do not require follow-up imaging. Major renal lacerations and vascular pedicle injuries, however, often result in loss of renal function and should be followed up closely due to the risk of delayed complications. Follow-up examinations should continue for 3-4 months until healing is documented.

Nonoperative management of major blunt renal trauma in children: in-hospital morbidity and long-term followup

The management of 26 children with major renal injury secondary to blunt trauma was reviewed. Emergency computerized tomography (CT) was performed in all instances. Injury ranged from parenchymal laceration to vascular avulsion. Early surgical exploration was done in 5 children due to hemodynamic instability, renal pedicle injury or suspected malignancy. The remaining 21 children were observed. Of these children 5 had associated intra-abdominal organ injuries. The average length of hospitalization was 13.4 days and the average intensive care unit stay was 6.9 days. A third of the children were transfused with an average 10.8 cc/kg. of packed red cells. Ten patients (47.6%) had febrile episodes that lasted an average of 3 days. No foci of infection other than bladder urine were identified and there were no infected perirenal collections. In 2 children ureteral stents were placed cystoscopically. Exploration was performed in 1 child for delayed hemorrhage 2 months after hospital discharge. Followup CT was available in 15 patients and all kidneys functioned, including 3 with residual focal scarring, 2 with parenchymal calcifications and 1 with a cyst. Eleven patients were evaluated clinically at least 1 year after injury and all were asymptomatic, while 1 child had mild diastolic hypertension. In conclusion, nonoperative management results in an excellent long-term outcome in the majority of cases. In-hospital morbidity is minimal and early surgical exploration should be reserved for those with hemodynamic instability or renal pedicle injury. Immediate CT is an invaluable aid in categorizing and managing these patients.

Selective surgical management of renal stab wounds

Patients with stab wounds and haematuria were selected for surgical exploration if they had signs of severe blood loss, an associated intra-abdominal laceration or major abnormality on the intravenous urogram (IVU). Patients without these signs were selected for non-operative management, consisting of bed rest, an intravenous antibiotic for 24 h and regular observation. Of 95 patients, 60 (63%) were selected for non-operative management (Group 1) and 35 (37%) were selected for primary surgical exploration (Group 2). At surgery in Group 2, a major renal injury and/or associated intra-abdominal laceration was found in 31 patients. Thus a probably unnecessary operation was performed in only 4 patients (4% of the whole group of 95 patients). Renal complications occurred in 12 of the 60 patients (20%) in Group 1 and consisted mainly of secondary haemorrhage caused by an arteriovenous fistula (AVF) or pseudo-aneurysm. Management of the renal complications included segmental artery embolisation in 6, nephrectomy in 2, heminephrectomy in 1, open surgical ligation of an AVF in 1 and spontaneous resolution in 2 patients. The mean period of hospitalisation was significantly shorter in Group 1 (6.1 days) than in Group 2 patients (9.9 days). Comparing the Group 1 patients who developed renal complications with those who did not, we would recommend more aggressive selection for surgery of those patients exhibiting clinical signs of shock, a fall in haemoglobin during observation, a palpable abdominal mass, a haemothorax and/or pneumothorax ipsilateral to the renal injury, and IVU signs of extravasation, non-function, delayed excretion or hydroureteronephrosis due to blood clots.(ABSTRACT TRUNCATED AT 250 WORDS)

Sports and the Male Genitourinary System

In brief: Contusions and minor lacerations, the most common renal injuries, require conservative treatment, and the athlete must refrain from strenuous activities for 2 to 3 weeks. Most patients with hematuria have a renal contusion at most and do not need contrast studies. Underlying renal abnormalities, pyelonephritis, and stone disease are occasionally seen. Patients who have gross hematuria after strenuous jogging or marathons should not run with an empty bladder. The smoke- or tea-colored urine that occurs after athletic endeavors usually resolves without sequelae within 24 hours and requires no further evaluation.

Renal Imaging Following Blunt Trauma

In brief: Athletic participation may result in blunt or penetrating trauma to the genitalia, perineum, pelvis, back, flank, or abdomen. Such acute trauma can induce urinary tract injury heralded by hematuria, but the possibility of such injury should be considered even in the absence of urinary tract symptoms. Selection of the most efficacious renal imaging method-computed tomography or intravenous pyelography-is essential in order to optimally manage athletes with urinary tract trauma.