Investigation and management of blunt renal injuries in children: a review of 11 years' experience

Over an 11-year period, 333 patients aged 6 months to 13 years were investigated for suspected blunt renal trauma. Ninety-one renal injuries were demonstrated. All patients who had preexisting pathology sustained major (ie, grade III or IV) injuries and all those who required surgery presented with 4+ or macroscopic hematuria with or without loin signs. Intravenous pyelography (IVP) showed no injury in 140 (89%) of 157 patients who had 0 to 3+ microscopic hematuria, and did not influence management in the remaining 17 patients. Seventy-eight (84%) patients were treated nonoperatively, with one death and few complications. Thirteen (14%) patients underwent early laparotomy, with a nephrectomy rate of 92%. No patient with a renal pedicle injury was considered suitable for vascular reconstruction. We conclude that (1) contrast studies are of little value in pediatric patients with asymptomatic microscopic hematuria after blunt trauma; (2) IVP remains the most cost-effective means of investigating renal injuries; and (3) laparotomy is only indicated for ongoing hemorrhage from the severely injured kidney and in a few selected patients with renal pedicle injuries.     

Clinical indications for radiographic evaluation of blunt renal trauma

The evaluation of patients with blunt renal trauma has become controversial. We tested the hypothesis that renal contusion can be diagnosed clinically and that these patients do not require radiographic evaluation. To evaluate the association of microhematuria without shock and with renal contusion, we reviewed the medical records of 831 patients with hematuria following blunt renal trauma. Microscopic hematuria without shock was noted in 160 of 241 patients without and 334 of 590 with associated injuries. Of the former 160 patients 159 had renal contusion and 1 had a renal laceration, while of the latter 334 patients 329 had renal contusion, 3 had renal laceration, 1 had renal rupture and 1 had a pedicle injury. Most patients with microscopic hematuria and no shock after blunt renal trauma had a renal contusion, especially those with no associated injury. All of the patients with renal contusions experienced no complications from nonoperative management. However, avoiding a radiographic evaluation in patients with blunt renal trauma plus microhematuria and no shock would miss a few cases of severe renal injury.     

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.     

Renal pedicle injury in the multiple injured patient

Renal pedicle injuries were associated with multiple system trauma and a mortality rate of 42 per cent in 31 patients seen from 1959 to 1978. These injuries were to the renal artery in 14 patients, branches of the renal artery in 5, renal vein in 8, and renal artery and vein in 4. Priority of treatment for life-threatening associated injuries resulted in delayed diagnosis of the renal pedicle injury, which was not optimal for preservation of functioning renal tissues. Since 1968 an immediate excretory urogram has been performed for hematuria or a perirenal hematoma found during laparotomy for associated injuries. This study has resulted in the early diagnosis of renal pedicle injuries and immediate vascular repair has been attempted in 6 patients. Three of these patients survived with no hypertension on followup. A repaired renal vein in 1 patinet resulted in normal renal function and renal arteries were repaired in the other 2 patients with reduced renal function.     

Grade IV Renal Injuries: Evaluation, Treatment, and Outcome

Of our last 2483 renal trauma patients, 113 had grade IV injuries. In most the mechanism was a penetrating injury (60%: 30% gunshot, 30% stab wounds). Associated injuries were common (80%) and hospital stays prolonged, averaging 16 days. Most of the patients (70%) required transfusion, some massively (average volume 4.4 liters, range 0-30 liters). Surprisingly, not all patients with grade IV renal injuries had gross hematuria: 25% had microhematuria, and 4% had neither microscopic nor gross hematuria. Computed tomography (CT) diagnosed the injury correctly in 100% of the patients in whom it was performed; when CT was not available, "one-shot" intraoperative intravenous pyelography (IVP) demonstrated grossly abnormal findings in 90%. Renal exploration was performed in 78%, resulting in 69% renorrhaphy and 9% nephrectomy rates in our 113 patients. Almost all those with penetrating trauma required exploration (97%), whereas only 50% of those with blunt trauma did so. The overall complication rate and kidney-specific complication rate did not differ significantly between patients who were observed and those who underwent surgery. Complications rates were similar in grade IV renal laceration patients and grade III patients. Delayed complications after hospital discharge were not seen, although follow-up was rare in this inner-city trauma population. Among the 21% of patients in whom postoperative nucleotide renal function scans were available, function was generally good (average 36%). Only patients who underwent concomitant vascular repair had poor function (below 20%).     

Blunt renal pelvic and ureteral injury in multiple-injured patients

The presence of multiple severe injuries influences the management and results with blunt renal pelvic and ureteral injury. Our 9 patients had an average of 4.5 associated injuries per patient and associated renal pedicle injuries in 4 patients. The poor general condition of the multiple-injured patient precluded the optimal management of the blunt renal pelvic and ureteral injury in 5 of the 9 patients. Delayed repair was performed in 4 patients with a successful result in 3. The fourth patient had a complicated course resulting in nephrectomy. The delay in presentation and diagnosis of the renal pelvic or ureteral injury did not preclude a successful result with delayed repair.     

Intravenous pyelography in abdominal trauma

The present report is a retrospective review of 23 patients admitted to the University of Kentucky Medical Center during 1975 and 1976, selected because they had sustained renal trauma as ascertained by hematuria, intravenous pyelography (IVP), or operative intervention. The value of IVP was determined by the patients' eventual hospital course. Of five patients with penetrating injuries, all had hematuria and an intravenous pyelogram on admission. One of these patients did not require an operation. Among the 18 patients with blunt abdominal trauma, six of the 14 patients who had hematuria and an IVP on admission were spared operation. Four patients did not have hematuria, but all four had a renal lesion. Two of these patients required an operation: one for inspection of a traumatic left nephrectomy; the other for bilateral renal artery occlusion, successfully repaired after 16 hours. Whenever feasible all patients sustaining abdominal trauma should have an IVP regardless of whether or not hematuria is present.     

Renal reconstruction after injury

During an 11-year period 1,363 patients presented to our institution with renal trauma. Renal exploration was performed in 127 patients (133 renal units). Most patients had multiple organ injuries, as indicated by a mean blood loss of 4,160 ml. and a mean injury severity score of 25.8. Absolute indications for exploration were bleeding and pulsatile perirenal hematoma and relative indications included urinary extravasation, nonviable renal tissue and incomplete staging. Renal surgery was required in 2.4% of the blunt injuries, 45% of the stab wounds and 76% of the gunshot wounds. Salvage was successful in 88.7% of the kidneys explored and total nephrectomy was required in 11.3%. The success rate was based on early vascular control and reconstructive techniques of "renorrhaphy," partial nephrectomy, vascular repair and coverage with omental pedicle flaps. Complications occurred in 9.9% of the cases but none resulted in renal loss. When indicated, renal exploration after trauma is safe and in a high percentage of cases reconstruction will be successful.     

Renal vascular injuries

Fifteen patients with injuries to the renal arteries and/or veins have been treated in the past ten years. Nine injuries were the result of gunshot wounds, and six were from blunt trauma. Twelve patients presented to the emergency department in shock; two of these did not have a palpable blood pressure. Time from admission to time of operation averaged 6.4 hr for patients with blunt trauma and 1.25 hr for patients with penetrating trauma. Seven patients had ten associated abdominal vascular injuries, and two patients had injuries to both the right renal artery and left renal vein. Associated nonvascular abdominal injuries were found in all 15 patients. Efforts were made to repair renal vascular injuries with suture or grafting of the injured vessel in eight cases (53%). These efforts were successful in four patients, but in four the repair failed and a nephrectomy could not be avoided. Two patients died in the operating room or immediately postop in spite of successful repair of their renovascular injury. One injured left renal vein was ligated and nephrectomy was not necessary. In five patients, ligation of the injured renal artery and nephrectomy were necessary. There were five deaths (33%). Three of the deaths occurred in the operating room and two were postoperative deaths. Only one of the patients who died had a renal vessel injury without other major vessels involved. He did, however, have serious liver and kidney injuries. Multiple associated vascular, nonvascular, and head injuries were present in all four of the other deaths. We have continued to take an aggressive approach to exploration, isolation of the injury, and repair of the vessel whenever possible if a renal vessel injury is suspected.(ABSTRACT TRUNCATED AT 250 WORDS)     

The role of IVP in blunt trauma

To investigate the role of the IVP, we studied 139 patients with blunt abdominal trauma and hematuria. Multivariate analysis of clinical parameters was utilized in attempt to predict which patients would have abnormal IVP's and which would eventually require genitourinary operation. Thirty-four patients (25%) demonstrated abnormalities on IVP; however, no combination of clinical findings (including degree of hematuria) could reliably predict which patients would have abnormal IVP's. On the other hand, in 90% of the patients, the necessity for genitourinary operation could be reliably predicted based on: presence of blood at the urethral meatus, degree of hematuria, patient age, Injury Severity Score, and number of rib fractures. We conclude that to detect IVP abnormalities, IVP's need to be performed on all blunt trauma patients with hematuria. However, patients likely to have injuries requiring operative repair can be predicted. Those patients unlikely to have genitourinary injury requiring repair, therefore, may have IVP performed on a nonurgent basis.     

Microscopic hematuria after blunt trauma. Is pyelography necessary?

Hematuria after blunt abdominal trauma is common with multiple organ system injuries, and many trauma centers routinely perform intravenous pyelography (IVP) on all trauma patients having any degree of hematuria. However, it has been suggested that many IVPs could be avoided if more selective criteria were used. To help determine the need for an IVP, we reviewed the records of 102 consecutive patients undergoing IVP after blunt abdominal trauma over a 17-month period. Twenty-six (25%) patients had gross hematuria. Of these, seven (27%) had abnormal IVPs, and two (7.7%) of those required urologic surgery. Seventy-six (75%) patients had microscopic hematuria. Of these, one (1.3%) had an abnormal IVP but required no urologic surgery. Thus, if IVP had been performed only when gross hematuria was present, then all surgically significant urinary tract lesions would have been recognized, and 75 per cent of these 102 patients would have been spared IVPs. We agree with others that microscopic hematuria alone is not an indication for emergency IVP in these trauma patients. However, gross hematuria or other strong clinical evidence of renal injury still mandates IVP early during the assessment of patients who have suffered blunt abdominal trauma.     

Efficacy of Radiographic Imaging in Pediatric Blunt Renal Trauma

Purpose

We sought to determine whether radiographic imaging can effectively detect significant renal injuries in children with blunt trauma who do not have significant hematuria.

Materials and Methods

We reviewed the records of 180 children who presented to our hospital for suspected renal trauma between 1977 and 1995. Results of excretory urography or abdominal computerized tomography were correlated with urinalysis findings and clinical outcome.

Results

Of 147 patients with microscopic hematuria after blunt trauma 77 underwent imaging. Only 1 patient had a significant renal injury (grade 2 or greater) and 76 had normal findings or renal contusions only, including 11 with microscopic hematuria and shock. Of the 74 patients who did not undergo imaging a clinical diagnosis of renal contusion was made and followup was available for 57 (77 percent). All patients healed without adverse sequelae. Of 33 patients with gross hematuria significant renal injuries were found in 9, including 3 who required immediate surgical repair of a major renal laceration or vascular injury. Combining our results with those of other reported series revealed significant renal injuries in only 11 of 548 children (2 percent) with less than 50 red blood cells per high power field on presenting urinalysis after blunt abdominal trauma. These patients were likely to have multiple associated injuries.

Conclusions

Significant renal injuries are unlikely in pediatric patients with blunt renal trauma but no gross or substantial microscopic hematuria. Shock does not appear to be a clinically useful indicator.     

Popliteal artery trauma: a high risk injury

The clinical presentation and management of 28 popliteal artery injuries following penetrating and blunt trauma during a 6 year period is reviewed. Clinical and Doppler evaluation identified an arterial injury in 24 (85 per cent) patients. In eight (29 per cent) patients with arteriovenous fistulae or false aneurysms, pedal pulses were palpable during initial assessment. Three (10.7 per cent) patients had limb amputation attributable to delayed vascular repair, crush injury and sepsis. End-to-end arterial repair following blunt trauma resulted in early failure with thrombosis in two patients. Autogenous vein grafting was used in 12 patients and is advocated in all blunt popliteal arterial injuries. Routine repair of associated venous injuries and liberal criteria for early fasciotomy were used. Exoskeletal fixation or skeletal traction for compound and comminuted fractures is recommended for simplicity of application and wound management. The significant functional orthopaedic disability following blunt arterial trauma at the knee is emphasized.     

Hematuria following blunt abdominal trauma. The utility of intravenous pyelography

To clarify the indications for intravenous pyelography (IVP) and nephrotomography (NT) in the evaluation of patients with hematuria following blunt thoracoabdominal trauma, we performed a retrospective analysis of patients admitted during a one-year period who had undergone IVP and NT for suspected renal injury. One hundred thirty-four patients were reviewed, and the findings of IVP and NT correlated with the magnitude of hematuria on urinalysis, associated injuries, management, and outcome. Sixty-two (46%) of 134 patients had fewer than ten red blood cells per high-power field (RBCs/HPF) on urinalysis (group 1), 19 (14%) of 134 patients had 10 to 30 RBCs/HPF (group 2), and 53 (40%) of 134 patients had greater than 30 RBCs/HPF (group 3). Twenty-seven patients had renal injuries detected by IVP and NT, two in group 2 and 25 in group 3. We conclude that IVP and NT should be reserved for patients with greater than 30 RBCs/HPF on admission urinalysis.     

Delayed presentation of arteriovenous fistula 20 years after blunt renal trauma

Delayed hematuria following blunt trauma is rare but can be significant. We describe an unusual delayed presentation of renal arteriovenous fistula following blunt trauma. A gentleman presented with hematuria and clot colic. Following initial investigations, renal arteriography showed an arteriovenous fistula in the mid-pole of the right kidney. The fistula was successfully occluded by super-selective coil embolization. Although this case is an unusual presentation, AV fistulae must be ruled out in management of patients of hematuria.     

Renal trauma: re-evaluation of the indications for radiographic assessment

We studied prospectively 359 consecutive patients with blunt (306) or penetrating (53) renal trauma to refine the indications for radiographic evaluation. Various factors, including the degree of hematuria, presence of shock and associated injuries easily assessable at the time of initial evaluation, were correlated with the severity of renal injury to determine whether any combination of parameters will separate patients with renal contusions from those with significant renal injuries (minor and major lacerations, and vascular injuries). We identified 3 groups: group 1-85 patients with gross hematuria or microscopic hematuria and shock after blunt trauma (including all 23 with significant renal injuries), group 2-221 patients with microscopic hematuria but no shock after blunt trauma (all with renal contusions) and group 3-53 patients with penetrating trauma. No combination of parameters was able to predict a severe injury in group 3. Our data support radiographic evaluation in groups 1 and 3. However, because all patients in group 2 had renal contusions and experienced no complications from nonoperative management we believe that excretory urography, which is time-consuming and costly, can be avoided in patients with microscopic hematuria but no shock after blunt renal trauma.     

Routine Preoperative “One-Shot” Intravenous Pyelography Is Not Indicated in All Patients With Penetrating Abdominal Trauma

Background: To determine which patients need a “one-shot” intravenous pyelogram (IVP) before laparotomy for penetrating abdominal trauma.

Study Design: Over a 15-month period, 240 laparotomies were performed for penetrating trauma at our urban level I trauma center. Prospectively collected data included clinical suspicion of genitourinary injury, results of preoperative IVP, intraoperative findings, and operative decisions influenced by the IVP.

Results: Preoperative IVP was performed in 175 patients (73%). Of these, 71 (41%) had suspicion of a renal injury based on the presence of a flank wound or gross hematuria. The IVP was believed to influence operative decisions in six patients, all in this group. Each of these six patients had either a shattered kidney or a renovascular injury and had a nephrectomy performed with the knowledge that a normal functioning kidney was present on the contralateral side. No patient without a flank wound or gross hematuria had an IVP that was judged to be helpful intraoperatively. Preoperative IVP was helpful only in patients with flank wounds or gross hematuria. Nephrectomy was performed in two additional patients who did not undergo IVP, both of whom presented in shock.

Conclusions: Routine preoperative IVP is not necessary in all patients undergoing laparotomy for penetrating trauma. The number of IVPs can be safely reduced by 60% if the indications are narrowed to include only those stable patients with a flank wound or gross hematuria.     

Emergency intravenous pyelography in the trauma patient. A reexamination of the indications

Because of the high incidence of abnormal intravenous pyelograms (IVPs) in victims of blunt trauma undergoing resuscitation, a retrospective review of the Trauma Registry at the University of California, San Diego Medical Center, was undertaken to evaluate the indications for ordering this test. The charts of 216 patients were reviewed, all of whom had formal IVPs (four films) done as an emergency procedure at the time of admission. In this study, special attention was directed toward comparing both the degree of hematuria and the anatomic site of injury with the results of the IVP. A total of 20 renal injuries was detected by IVP. Of these injuries, all but one had hematuria that was greater than 50 red blood cells per high-power field. All but one of the abnormal IVPs were associated with obvious abdominal injuries. The results of the IVP influenced the clinical course of only one patient in the entire series. We conclude that the use of the formal IVP (four films) in the resuscitation phase of treating the multiply traumatized patient be reserved for those patients with penetrating abdominal injury or with hematuria consisting of greater than 50 red blood cells per high-power field. For any major blunt abdominal trauma without significant hematuria, a more simple and rapid study (one-shot IVP) to demonstrate bilateral nephrograms is probably adequate to rule out occult renal artery thrombosis.     

Radiologic Evaluation of Pediatric Blunt Renal Trauma in Patients with Microscopic Hematuria

As a result of the rapid increase in medical costs, the efficacy of diagnostic imaging is under examination, and efforts have been made to identify patients who may safely be spared radiographic imaging. We reviewed the records of children who presented to our institution with suspected blunt renal injuries to determine if radiographic evaluation is necessary in children with microscopic hematuria and blunt renal trauma. We retrospectively reviewed the medical records of 1200 children (ages less than 18 years) who sustained blunt abdominal trauma and who presented to our level I pediatric trauma center between 1995 and 1997. Urinalysis was performed in 299 patients (25%). Urinalysis results were correlated with findings on abdominal computed tomography (CT). All patients had more than three red blood cells per high power field (RBC/ hpf) or gross hematuria. Renal injuries were graded according to the injury scale defined by the American Association for the Surgery of Trauma. Sixty-five patients had microscopic hematuria. Thirty-five (54%) were evaluated with an abdominal CT scan. Three patients sustained significant renal injuries (grade II-V), and 32 patients had normal findings or renal contusions. Therefore only 3 of 65 patients (4.6%) sustained a significant renal injury. All three patients had other associated major organ injuries. Of the three patients with gross hematuria evaluated with abdominal CT, one (33%) sustained a significant renal injury and had no associated injuries. The degree of hematuria did not correlate with the grade of renal injury. Pediatric patients with blunt trauma, microscopic hematuria, and no associated injuries do not require radiologic evaluation, as significant renal injuries are unlikely. However, children who present with associated injuries and microscopic hematuria after blunt trauma may have significant renal injuries and should undergo radiologic evaluation.     

Blunt renal artery injury: incidence, diagnosis, and management.

Renal artery injury is a rare complication of blunt abdominal trauma. Increasing use of CT scans to evaluate blunt abdominal trauma identifies more blunt renal artery injuries (BRAIs) that may have otherwise been missed. We identified patients with BRAI to examine the incidence and to evaluate the current diagnosis and management strategies. Patients admitted from 1986 to 2000 at a regional Level I trauma center sustaining BRAI were evaluated. Patients undergoing revascularization or nonoperative management were followed for renovascular hypertension. Twenty-eight patients with BRAI were identified out of 36,938 blunt trauma admissions between 1986 and 2000 (incidence 0.08%). Most renal artery injuries were diagnosed by CT scans (93%) with seven confirmatory angiograms. Nine patients had nephrectomy (one bilateral), and three patients with unilateral injuries were revascularized. Sixteen were managed nonoperatively including one patient who had endovascular stent placement. Three patients died from shock and sepsis. Follow-up for all patients ranged from one month to 8 years. Two patients developed hypertension: one who was revascularized (33%) and one was managed nonoperatively (6%). The frequency of diagnosis of BRAI is increasing because of the increased use of CT. Nonoperative management of unilateral injuries can be successful with a 6 per cent risk for developing renovascular hypertension. The role of endovascular stenting is promising, and further study is necessary.