The levels of recommendation (I-III) and classes of evidence (I-III) are defined at the end of the "Major Recommendations" field.
Renal Trauma
Level I
There is insufficient Class I and Class II data to support any standards regarding evaluation of renal trauma.
Level II
- Patients who require urologic imaging after blunt trauma include those with gross hematuria and those with microscopic hematuria in the face of hemodynamic instability. Microscopic hematuria can be reliably detected using urine dipstick, although different brands of dipstick may have different levels of sensitivity and specificity.
- Computerized tomography (CT) has a higher sensitivity and specificity in the evaluation of blunt renal trauma as compared to intravenous pyelography (IVP) and is the diagnostic modality of choice in imaging patients with suspected blunt renal trauma.
- Magnetic resonance imaging (MRI) equals CT in correctly grading blunt renal injuries and detecting the presence and size of perirenal hematomas. MRI differentiates intrarenal hematoma from perirenal hematoma more accurately and is able to determine recent bleeding in the hematoma by regional differences in signal intensity. Although MRI can replace CT in patients with iodine allergy and may be helpful in patients with equivocal findings on CT, it should be reserved for selected patients, due to increased cost and increased imaging time.
Level III
- There is a correlation between degree of hematuria in blunt trauma and likelihood of significant intra-abdominal injury not related to the genitourinary system.
- Negative ultrasound does not exclude renal injury.
- There is no correlation between presence and amount of hematuria and extent of renal injury after penetrating trauma.
- Limited one-shot IVP is of no significant value in assessing penetrating abdominal trauma patients prior to laparotomy, other than to determine the presence of a second kidney prior to nephrectomy.
- CT should be the primary diagnostic study in penetrating trauma at risk for renal trauma. Renal hematoma area: total body area may be helpful in determining the grade of renal injury.
- In penetrating renal trauma, after IVP or CT, renal angiogram is the second study of choice because it reliably stages significant injuries and offers the possibility of embolization.
Ureteral Trauma
Level I
There is insufficient Class I and Class II data to support any standards regarding evaluation of ureteral trauma.
Level II
There is insufficient Class II data to support any recommendations regarding evaluation of ureteral trauma.
Level III
- Urinalysis, IVP, and operative exploration may miss ureteral injuries, requiring a high index of suspicion during celiotomy.
- Delaying spiral CT for 5 to 8 minutes after contrast infusion may increase the sensitivity in detecting ureteral disruption from blunt trauma.
Bladder Trauma
Level I
There is insufficient Class I and Class II data to support any standards regarding evaluation of bladder trauma.
Level II
- Routine CT of the abdomen alone (without cystography) is inadequate to detect bladder rupture, even when the Foley is clamped and bladder distended.
- CT cystography is as accurate as conventional cystography in the detecting bladder rupture and may be used interchangeably with conventional cystography.
- Gross hematuria, pelvic fluid, pelvic fractures (other than acetabular fractures) on CT should prompt conventional cystography or CT cystography. Drainage films and adequate distension of the bladder with contrast medium increases the sensitivity of cystography in the detection of bladder injuries.
Level III
There are no Level III recommendations for the evaluation of bladder trauma.
Urethral Trauma
Level I
There is insufficient Class I and Class II data to support any standards regarding evaluation of urethral trauma.
Level II
Urethral injury should be suspected when a pubic arch fracture exists and an urethrogram performed. The risk of urethral injury is increased when there is involvement of both the anterior and posterior pelvic arch.
Level III
- Although blood at the urethral meatus, gross hematuria, and displacement of the prostate are signs of disruption and should prompt urologic work-up, their absence does not exclude urethral injury. Successful passage of a Foley does not exclude a small urethral perforation.
- Although the female urethra is relatively resistant to injury, it should be suspected in patients with either vaginal bleeding or external genitalia injury or with severe pelvic fractures and incontinence problems.
Renovascular Trauma
Level I
There is insufficient Class I and Class II data to support any standards regarding evaluation of renovascular trauma.
Level II
There is insufficient Class II data to support any recommendations regarding of renovascular trauma.
Level III
There is insufficient Class III data to support any recommendations regarding evaluation of renovascular trauma.
Definitions:
Rating Scheme for Strength of Recommendations
Level I
The recommendation is convincingly justifiable based on the available scientific information alone. This recommendation is usually based on Class I data; however, strong Class II evidence may form the basis for a Level I recommendation, especially if the issue does not lend itself to testing in a randomized format. Conversely, low quality or contradictory Class I data may not be able to support a Level I recommendation.
Level II
The recommendation is reasonably justifiable by available scientific evidence and strongly supported by expert opinion. This recommendation is usually supported by Class II data or a preponderance of Class III evidence.
Level III
The recommendation is supported by available data but adequate scientific evidence is lacking. This recommendation is generally supported by Class III data. This type of recommendation is useful for educational purposes and in guiding future clinical research.
Rating Scheme for Strength of Evidence
Class I
Prospective randomized controlled trials
Class II
Clinical studies in which the data was collected prospectively, and retrospective analyses which were based on clearly reliable data. Types of studies so classified include: observational studies, cohort studies, prevalence studies, and case control studies.
Class III
Studies based on retrospectively collected data. Evidence used in this class includes clinical series and database or registry review.
