Management Contusion
7.6 Urethral trauma
◦ Combined bladder injury
Features of both intra and extra peritoneal rupture are present.
◦ Penetrating injuries
May result in intraperitoneal, extraperitoneal, or combined bladder ruptures.
Management
7.6 URETHRAL TRAUMA 137
Clinical presentation
• Blunt trauma such as pelvic fracture, straddle injury, or blow to the perineum should increase the clinical suspicion for urethral injury.
• The typical clinical triad is
◦ blood at the urethral meatus
◦ inability to void
◦ a palpable urinary bladder.
• Other clinical findings include
◦ high riding prostate upon digital rectal examination
◦ perineal hematoma.
Classification of urethral injuries
• Type I
◦ Posterior urethra intact but stretched(Fig. 7.8a, b).
◦ Uncommonly recognized injuries.
◦ Occur when the puboprostatic ligaments are ruptured but the continuity of the urethra is preserved.
• Type II
◦ Pure posterior injury with tear of membranous urethra above the urogenital diaphragm – partial or complete. (Fig. 7.8c, d).
◦ The urogenital diaphragm remains intact.
◦ This injury comprises 15% of urethral injuries resulting from pelvic fracture.
• Type III
◦ Combined anterior/posterior urethral injury with disruption of urogenital diaphragm – partial or complete. (Fig. 7.8e –g).
◦ The most common type of urethral injury, and represent a combined anterior/posterior urethral injury.
• Type IV
◦ Bladder neck injury with extension into the urethra.(Fig. 7.8h, i).
◦ The bladder neck laceration may damage the internal urethral sphincter.
• Type IVa
◦ Pure injury of the base of the bladder with periurethral extravasation simulating a true type IV urethral injury (Fig. 7.8k–m).
• Type V
◦ Pure anterior urethral injury – partial or complete. (Fig. 7.8n–p).
◦ Typically occur following a straddle injury and are more often partial than complete.
(a) (b)
(c) (d)
(e) (f)
Figure 7.8 Urethral injuries Type I urethral injury, posterior urethra intact but stretched (a) Retrograde urethrogram shows posterior urethral stretching and narrowing. (b) Diagrammatic illustration reproduced from SM Goldman et al., J. Urol. 57: 85–89, 1997 with permission.
Type II urethral injury, pure posterior injury with tear of membranous urethra above the urogenital diaphragm. (c) Urethrogram shows contrast extending from UG diaphragm (arrow) and above.
(d) Diagrammatic illustration reproduced from SM Goldmanet al., J. Urol.57:85–89, 1997 with permission.Type III urethral tear with complete disruption of UG diaphragm. (e) Cystogram shows extensive extravasation above and below the UG diaphragm. (f) Note bladder base is elevated and symphysis pubis widened. Contrast is seen leaking below the symphysis pubis and therefore, represents a tear through the UG diaphragm.
7.6 URETHRAL TRAUMA 139
(i)
(j) (k)
(h)
(g)
Figure 7.8 (Continued) (g) Diagrammatic illustration reproduced from SM Goldman et al., J.
Urol.57: 85–89, 1997 with permission.Type IV urethral injury, bladder neck injury with extension into the urethra. (h) Contrast noted at base of bladder extending along posterior urethra (upper arrow). Contrast ‘clearly extends to the level of the membranous urethra, but not past the UG diaphragm (lower arrow). (i) Diagrammatic illustration reproduced from SM Goldman et al,. J.
Urol. 57: 85–89, 1997 with permission.Type IVA urethral injury, pure injury of the base of the bladder with periurethral extravasation simulating a true type IV urethral injury. (j) Retrograde urethrogram shows extravasation from bladder base (arrows) mimicking a high posterior urethral tear. (k) CT shows contrast extending along anterior abdominal wall muscles and subcutaneously (arrows).
(l)
(m)
(o) (n)
Figure 7.8 (Continued) (l) Diagrammatic illustration reproduced from SM Goldmanet al., J.
Urol.57: 85–89, 1997 with permission.Type V injury (anterior urethral injury). (m) Diagrammatic illustration reproduced from SM Goldmanet al., J. Urol.57: 85–89, 1997 with permission. (n) Retrograde urethrogram shows rupture of the anterior urethra (arrows) and extravasation of contrast from the urethra into the surrounding tissue and venous drainage. (o) Urethrogram shows tear of the urethra secondary to a bullet.
Outcome
• Complete type II and III lacerations result in complete urethral strictures, which are usually repaired on a delayed basis, typically six months after the initial injury.
• This delay provides an opportunity for the pelvic fractures to stabilize and for the pelvic hematoma to resolve so that the bladder has descended into the pelvis.
• In general, type II injuries result in shorter strictures that are easier to repair.
• Recognition of bladder neck injury (type IV and IVA) is important to prevent urinary incontinence.
Imaging
• Diagnosis is made by a retrograde urethrogram, which must be obtained prior to an attempt to place a urethral catheter.
• A Foley catheter is inserted into the penile urethra and its balloon is partially inflated within the fossa navicularis.
7.6 URETHRAL TRAUMA 141
• No lubricant is used and an exposure is acquired during the active injection of 20–30 ml of a water soluble contrast medium (300 mgI/ml) so that the deep bulbar and prostatic urethras will be filled.
• Ideally this should be performed under fluoroscopic control but this is not always available in the accident and emergency department.
Findings at urethrogram of urethral injury
• Type 1 (Fig. 7.8a, b)
◦ The posterior urethra is stretched as a hematoma forms in the prostatic fossa, displacing the bladder slightly upward.
◦ Extrinsic compression of the posterior urethra by a periurethral hematoma without displacement of the bladder base is not considered a true type I injury.
• Type II (Fig. 7.8c, d)
◦ Partial or complete laceration of the posterior urethra.
◦ Extravasated contrast material is confined to the pelvic extraperitoneal space above the urogenital diaphragm.
• Type III (Fig. 7.8e –g)
◦ Membranous urethral tear.
◦ The tear extends into the proximal bulbous urethra.
◦ Contrast will extravasate below the urogenital diaphragm into the perineum.
• Type IV (Fig. 7.8h, i)
◦ Tear of the bladder neck that extends into the proximal urethra.
• Type IVA (Fig. 7.8j–m)
◦ Radiographically indistinguishable from true Type IV injuries, as both demonstrate periurethral contrast extravasation.
• Type V (Fig. 7.8n–o)
◦ Anterior urethral disruptions
If Buck’s fascia (the deep fascia of the penis that binds the three cylindrical erectile bodies in the pendulous portion of the penis) remains intact, then the extravasation is confined to the space between Buck’s fascia and the tunica albuginea [the thick connective tissue layer that surrounds the erectile tissue around the urethra (corpus spongiosum)].
If Buck’s fascia is ruptured, extravasated contrast will be confined by Colle’s fascia (a layer of superficial penile fascia invests the Buck’s fascia).
Clinical management
• Repair of urethral injuries may be done in primary (soon after the injury) or in a delayed fashion.
• Primary reapproximation of the severed urethral stumps
◦ Reserved for stable patients with a short urethral injury.
◦ Associated injuries of bladder, bladder neck or rectum may dictate the need for imme- diate primary repair.
◦ Not done routinely now due to the high rate of postoperative impotence and inconti- nence.
◦ The stricture rate is low.
• Delayed repair
◦ Initially only involves placing a suprapubic drainage catheter.
◦ Urethral strictures are universally present because no initial attempt is made to repair the urethra.
• Primary realignment by endoscopic approach
◦ Is now the preferred option.
◦ Some cases may be accomplished with one flexible retrograde cystoscope.
◦ Others may be realigned with two flexible cystoscopes introduced both retrograde and antegrade.
◦ Once a wire can bridge the gap of injury, a urethral catheter is placed and maintained for 4 to 6 weeks to allow the urethra to heal.
• In the unstable or multi-organ trauma patient
◦ A suprapubic catheter is placed to divert the urine during damage control and resusci- tation.
◦ Delayed realignment can be performed endoscopically a few days to two weeks later, once the patient is stable and resuscitated.
◦ When a delayed realignment is not possible, a delayed open urethroplasty or urethro- tomy is performed in 3 to 6 months.
• In isolated bladder neck injury, repair is needed but can be technically demanding, espe- cially in unstable patients.
• Women with proximal urethral disruptions should immediately undergo exploration with realignment of the urethral ends or primary reanastomosis over a catheter.
• For women with distal urethral lacerations, a urethral catheterization with primary closure of the vaginal laceration is adequate.