Pediatric emergency medicine trisk 831

CLINICAL PEARLS AND PITFALLS Ureteral injuries are often missed during the initial evaluation with less than 50% of patients diagnosed within 24 hours of presentation Avulsion of the ureter should be suspected when the CT urogram (10-minute delayed imaging after IV contrast administration) demonstrates extravasation of contrast material and nonfilling of the affected ureter CT findings suggestive of renal pelvis or ureteral injury include medial perirenal extravasation of contrast material, a circumrenal urinoma, and the lack of opacification of the ureter distal to the injury However, CT scan has been shown to be poorly sensitive for ureteral injury, identifying only 33% of cases in some series In case in which suspicion for ureteral injury is high, urologic consultation is necessary as retrograde pyelogram is a more reliable examination and offers the potential opportunity for therapeutic intervention Current Evidence Blunt trauma usually involves the UPJ Disruption of the ureter from the renal pelvis results from stretching of the ureter by sudden hyperextension of the trunk Traditionally, this injury has been described more often in children Penetrating injuries may occur at any point along the length of the ureter and are associated with injuries to other intra-abdominal organs in up to 90% of cases Stab wounds rarely cause ureteral injuries Ureteral injuries can occur iatrogenically during surgical procedures involving the retroperitoneum as the ureters may be obscured by bleeding or fibrosis While these situations occur far less common in children than adults, a high suspicion should be maintained in patients presenting with ongoing symptoms after retroperitoneal surgery, most commonly gynecologic, colorectal, vascular, or urologic procedures Clinical Considerations Clinical Recognition Trauma to the ureter should be suspected in patients presenting with fracture of the transverse process of a lumbar vertebra Pelvic fracture, hip fracture, lower rib fracture, splenic laceration, liver laceration, and diaphragmatic rupture have also been reported in association with ureteral injuries Gunshot wounds with a bullet course through the retroperitoneum should also prompt a high level of suspicion The physical examination may be unremarkable However, an enlarging flank mass in the absence of signs of retroperitoneal bleeding suggests urinary extravasation Hematuria is an unreliable sign The urinalysis may be normal in 30% of confirmed cases When the diagnosis has been delayed, ureteral injury may manifest with fever, chills, lethargy, leukocytosis, pyuria, bacteriuria, flank mass or pain, fistulas, urinoma, peritonitis, and ureteral strictures Management/Diagnostic Testing As mentioned above, the diagnosis of ureteral injury should be entertained when children present with penetrating abdominal injuries A CT urogram can suggest the presence of ureteral injury when the ureter does not opacify with contrast on delayed images and/or there is urinary extravasation medial to the renal hilum or along the length of the ureter Retrograde pyelogram may be considered if ureteral injury is suspected This generally requires sedation or anesthesia, and involves passing dye in a retrograde fashion from bladder into the ureter with fluoroscopic evaluation Clinical Indications for Discharge or Admission Given the strong association of ureteral injuries with other severe abdominal injuries, most children with ureteral injury are admitted to the hospital Urologic consultation is necessary for children with suspected ureteral injury These injuries require diversion of urine with a ureteral stent or nephrostomy tube Extensive injuries may require definitive repair in an immediate or delayed fashion BLADDER Goal of Treatment The goal of evaluation in the ED is recognition of bladder injuries, determining if they are extra- or intraperitoneal, and obtaining prompt urologic consultation CLINICAL PEARLS AND PITFALLS Bladder injuries may occur after blunt or penetrating trauma Blunt trauma secondary to motor vehicle accidents is the leading cause More than 80% of bladder injuries are associated with pelvic fractures; however, only 10% of patients with pelvic fractures sustain lower urinary tract injury The probability of having an associated bladder injury increases proportionally with the number of fractured pubic rami Current Evidence During childhood, the bladder has a higher abdominal location, which renders the organ more susceptible to injury than in adults The bladder can also be more easily damaged when full The risk for this injury is especially increased in the setting of improperly fastened seat belts and lap belts Bladder injuries are classified as extraperitoneal, intraperitoneal, or combined Extraperitoneal injuries are more frequently associated with pelvic fractures of the anterior ring and may be related to either laceration or penetration from a bone spike, irrespective of bladder volume at the time of injury In contrast, intraperitoneal injuries, which account for approximately two-thirds of major bladder injuries, are usually caused by blunt trauma, resulting in a burst mechanism to a full, distended bladder Combined injuries are usually seen with gunshot wounds Bladder injuries may range from contusions to rupture Contusions are incomplete, nonperforating tears of the mucosa Complicated injuries may involve the bladder, urethra, sacral plexus, and supporting structures of the anorectal region Bladder neck injuries are uncommon, but serious as this may affect continence or lead to extravasation into other areas such as the medial thigh Such injuries have been reported to be more common in children than in adults because of the undeveloped prostate and are often in association with a pelvic fracture The injury may be due to longitudinal lacerations or lacerations that extend to the proximal urethra Clinical Considerations Clinical Recognition Hematuria and dysuria are symptoms commonly seen at presentation Nearly 100% of patients with rupture of the bladder have gross hematuria Microscopic hematuria is associated with less severe injuries such as contusions Patients with intraperitoneal ruptures may develop a palpable fluid wave from extravasation of urine into the peritoneal cavity and peritoneal irritation with signs of peritonitis Elevated levels of blood urea nitrogen in the serum are out of proportion to creatinine resulting from more rapid peritoneal reabsorption of urea Patients with myelodysplasia who have undergone bladder augmentation may experience spontaneous bladder rupture in the presence of infection, bacteremia, or overdistension Suspicion must be high as they may lack the classic presentation seen in sensate patients Symptoms and signs of sepsis, as well as shoulder pain, may be encountered at presentation Emergent exploration is indicated after a cystogram is completed Urethral catheterization must be avoided if physical examination reveals blood at the urethral meatus or a high-riding prostate as urethral injury is possible Urologic consultation is required Initial Assessment/Diagnostic Testing A large, prospective series of pelvic fractures and lower genitourinary tract injury in pediatric patients found that imaging is not required if patients are stable, have a normal genitourinary examination, not have gross hematuria, and not have multiple associated injuries Diagnostic evaluation is indicated in patients who sustain pelvic or lower abdominal trauma with gross hematuria, inability to void, abnormal external genitourinary examination, or multiple associated injuries Evaluation begins with a plain radiograph to exclude a pelvic fracture Fracture types that have been associated with bladder injury include widening of the sacroiliac joint, symphysis pubis, and fractures of the sacrum If a pelvic fracture is not identified, the urethra can be catheterized and a cystogram is performed CT cystography should be performed for patients with suspected bladder injury after placement of a urethral catheter Sagittal and coronal multiplanar images may be helpful in identifying most sites of bladder rupture CT cystography does offer some advantages over plain cystography for patients undergoing CT scanning for the evaluation of other associated blunt injuries CT scanning provides expeditious scanning of the head, chest, abdomen, and pelvis; interpretation is often less affected by overlying bone fragments from pelvic fractures and spine boards than in the plain radiographic cystogram, and the CT can detect small amounts of intra- and extraperitoneal fluid, especially in the posterior position without need for a postdrainage film The disadvantages of CT cystography include the much higher radiation exposure and cost than those of plain radiographs Currently, the CT cystogram is recommended, when indicated, for patients undergoing CT scanning for other associated blunt trauma–related injuries With either modality, the bladder must be filled to an age-appropriate volume (∼350 cc in adults) to avoid missing injuries due to underdistension Management With few exceptions, treatment of bladder rupture is determined by whether the urine extravasation is confined to the extraperitoneal space or is intraperitoneal Extraperitoneal bladder rupture can generally be managed by urethral catheter or suprapubic drainage Extraperitoneal injuries with a bony fragment or foreign body in the bladder require surgical exploration  ... Testing A large, prospective series of pelvic fractures and lower genitourinary tract injury in pediatric patients found that imaging is not required if patients are stable, have a normal genitourinary