Pediatric emergency medicine trisk 830

Medial extravasation of contrast is often seen with UPJ ruptures and no contrast will be seen in the distal ureter on delayed images of complete UPJ avulsion Historically, diagnosis of UPJ injuries was delayed in 50% of cases but routine evaluation of trauma with CT, especially when delayed images are obtained, has increased the initial detection rate to almost 90% Ultrasound The focused assessment by sonography for trauma (FAST) is often used to evaluate trauma patients for abdominal injuries and intra-abdominal fluid collections Despite the availability and low risk nature of sonography, this modality has a low sensitivity (48%) for detecting renal injuries and often overlooks significant damages The use of contrast-enhanced ultrasound has recently been reported to increase the sensitivity to 69%, which is still inferior to the >90% sensitivity of CT Extravasation is also more difficult to visualize on ultrasound Currently used contrast preparations are not well excreted into the collecting system, limiting evaluation in the trauma setting This study is being utilized more often for follow-up of parenchymal injuries, especially in stable patients Intravenous Urography Although almost completely replaced by CT for evaluating stable trauma patients, the intravenous urogram or pyelogram still maintains a role in evaluating the unstable trauma patient taken directly to the operating room The main utility of this modality is to verify the presence of a functioning contralateral kidney The one-shot urogram is performed by giving a mL/kg body weight contrast bolus followed by plain film 10 minutes later Identifying a functional contralateral kidney is important first because every possible attempt should be made to save the injured kidney if it is the only one The injured kidney may lack contrast uptake if there is a major vascular injury or demonstrate a delayed nephrogram due to significant compression from a contained hematoma An abnormal renal outline, displacement of the bowel or ureter, and loss of the psoas margin are all suggestive of renal injury and hematoma Distinctive patterns of contrast extravasation that raise concern of a possible UPJ injury include extravasation medial or circumferential (circumferential urinoma) to the kidney Also, with a complete UPJ disruption, the ipsilateral ureter will lack intraluminal contrast The study is not particularly sensitive for picking up ureteral injuries FIGURE 108.3 Renal fracture Computed tomography section of the abdomen shows fracture of the left kidney with moderate subcapsular hematoma Angiography Angiography has been largely replaced by noninvasive modalities, especially in the pediatric patients in whom technical problems with vascular access result in a higher complication rate than in adults Arteriography does not add useful information to contrast CT scanning and may increase diagnostic delay during the preoperative workup It is however quite useful in patients who require therapeutic embolization of an active bleeding site (generally segmental artery or more distal) and may be considered as first-line therapy in such cases Nuclear Medicine Imaging and MRI Currently, there is no role for radionuclide imaging (DMSA, MAG3) or magnetic resonance imaging (MRI) in the acute setting for children with suspected renal trauma although there is a role in the follow-up evaluation of renal injury and long-term renal function Clinical Indications for Discharge or Admission In cases of blunt trauma, children with grade I renal injuries (contusions) can be discharged home without further imaging and followed with serial urinalyses Patients are instructed to limit daily activity until the urinalysis is within normal limits Outpatient radiographic evaluation is necessary if microscopic hematuria persists for more than 30 days Grade II and III renal injuries warrant admission to the hospital for a minimum of 24 hours when the risk of bleeding is highest Expectant treatment includes supportive care with bed rest, hydration, antibiotics, and serial hematocrits, although the evidence supporting these therapies is relatively low Once the gross hematuria resolves, these children may be discharged home with limited activity until microscopic hematuria resolves and repeat imaging demonstrates total healing Management of the remaining patients (with grade IV and V injuries) evokes significant controversy The shift from early operative intervention to a more expectant approach for most solid organ injuries has been increasingly applied to high-grade renal injuries Advocates of early surgical exploration argue that this approach results in decreases in morbidity, hospital stay, and complications without a significant increase in the risk for nephrectomy Opponents believe that nonoperative management of selected patients does not lead to negative consequences, may result in a higher renal salvage rate, and cuts down the morbidity associated with surgical exploration Nonoperative management requires admission to the hospital, serial examinations, and hematocrits Debate continues regarding the necessity of repeat CT scan at 36 to 72 for conservatively managed renal injuries According to expert opinion, repeat imaging is not required for grade I and II injuries and grade III injuries without hemodynamic instability or devitalized fragments Some authors are now beginning to advocate against routine repeat imaging for grade IV or V renal injuries when there is no clinical indication (e.g., sepsis, decrease in hematocrit, unstable blood pressure, increasing hematuria or oliguria), arguing that repeat scans rarely change the management of this population and that kidneys with stable or improved appearance on repeat CT still have a delayed complication rate of 25% Patients who demonstrate hemodynamic instability require surgical intervention or angiographic embolization of renal vessels Angioembolization should be performed only in those children who have a definable segmental artery injury Persistent urinary extravasation can be managed with percutaneous drainage or internal ureteral stenting These procedures, as well as embolization, should be limited to institutions that can provide appropriate resources Operative exploration is required in 5% to 10% of cases Absolute indications for renal exploration are life-threatening hemorrhage believed to be from renal injury, renal pedicle avulsion and expanding, pulsatile or uncontained retroperitoneal hematoma Relative indications include incomplete radiographic staging with concurrent traumatic injuries that require repair/exploration, extensive devitalized renal parenchyma, vascular injury, and significant urinary extravasation Attempts to preserve the kidney are more likely to succeed in patients with grade IV injuries Children with grade V injuries frequently require nephrectomy In patients with vascular injuries, chances of renal salvage are improved if renal parenchyma is minimally disrupted and revascularization is achieved within a few hours of the injury Penetrating renal injuries have traditionally been managed with operative intervention Compared with blunt trauma, far less literature is available in support of nonoperative treatment after penetrating trauma In addition, many recommendations are extrapolated from data on adult patient populations Careful selection of hemodynamically stable patients who can tolerate CT staging may identify a cohort of children who can be safely treated conservatively Indications for renal exploration are similar to those for injuries caused by blunt trauma Patients with penetrating trauma have a higher need for surgical intervention Short-term complications of renal trauma include delayed hemorrhage, urinary extravasation, abscess formation, and ureteral obstruction secondary to clot formation Drainage with a ureteral stent or percutaneous nephrostomy may be considered in cases of ongoing urinary extravasation Long-term complications include compromised renal function, hypertension, and arteriovenous fistula Chronic hypertension develops in a period ranging from days to 32 years, which is why patients with a history of renal trauma should undergo long-term yearly blood pressure monitoring URETER Goal of Treatment Ureteral injuries are uncommon in children and are often missed on initial evaluation As the ureters are well protected in the retroperitoneum, significant concomitant injuries are usually present The goal of emergency evaluation is to recognize the clinical scenarios in which ureteral trauma is possible so as to allow high suspicion for these injuries and prompt operative intervention These injuries occur in less than 1% of all genitourinary traumas  ... Angiography Angiography has been largely replaced by noninvasive modalities, especially in the pediatric patients in whom technical problems with vascular access result in a higher complication... segmental artery or more distal) and may be considered as first-line therapy in such cases Nuclear Medicine Imaging and MRI Currently, there is no role for radionuclide imaging (DMSA, MAG3) or magnetic... protected in the retroperitoneum, significant concomitant injuries are usually present The goal of emergency evaluation is to recognize the clinical scenarios in which ureteral trauma is possible