- Introduction
- Renal injury
- Ureteral injury
- Bladder trauma
- Urethral trauma
- Genital injuries
Introduction
Isolated trauma to the genitourinary system is rare. Urological injuries are more often seen in the multi-trauma patient. Injury to the urinary tract occurs in up to 10% of patients suffering from blunt or penetrating abdominal trauma. The aetiology of urological trauma varies between trauma centres, but the majority are due to blunt force.
It is important to establish priorities in the trauma patient and develop a consistent, systematic method of clinical assessment. Trauma to the urinary tract is rarely life-threatening, but can cause significant long-term morbidity, especially when diagnosis is delayed. In the case of patients with suspected urological trauma, as for all patients, the priorities are the same: establishing and maintaining an airway; ensuring adequate ventilation; cervical spine control; and providing adequate organ perfusion.
This chapter will outline the classification of genitourinary trauma, and important steps in diagnosis and management of these injuries. The wide availability of CT scanning has improved diagnostic accuracy of upper urinary tract injuries and reduced the requirement for operative exploration in stable patients, in favour of a more conservative approach.
While the vast majority of urological trauma may be managed nonoperatively, outcome depends on prompt recognition of injury and minimizing potential complications. The goal is always patient safety and preservation of kidney function. To this end, we will discuss clinical indications and guidelines for appropriate radiological evaluation. Management decisions are based on a combination of clinical and radiographic information.
Key points
- Isolated trauma to the genitourinary system is rare
- The vast majority of urological trauma may be managed nonoperatively
Renal injury
Renal trauma is traditionally classified in broad terms as major or minor. Major renal trauma includes large lacerations of the renal parenchyma with or without injury to the collecting system or the renovascular pedicle. Minor trauma includes simple laceration, renal contusion, and subcapsular haematoma (Fig. 10.1).
Minor trauma accounts for approximately 70% of renal injuries overall. Of the remaining major injuries, almost half involve the renovascular pedicle. While minor injuries are usually managed nonoperatively, there is widespread debate over the appropriate management of major renal injuries.
It may be more informative to classify renal trauma as blunt or penetrating, as this has more relevance with regard to management. Penetrating injuries should be explored with few exceptions. Most penetrating injuries to the kidney have other associated intraabdominal injuries, especially in the case of gunshot wounds. In contrast, the majority of blunt renal injuries may be managed by conservative measures; associated injuries are less common and usually less severe. In the Parkland Memorial Hospital series, all cases of blunt renal trauma which required surgery had associated nonrenal injuries (Feagins 1994).
The diagnosis of renal trauma is based on history, physical examination and radiographic evidence. A history of blunt or penetrating injury to the abdomen, back or flank or sudden deceleration accidents should all raise suspicion to the possibility of a renal injury. The patient may complain of flank pain or renal colic associated with clot haematuria. The patients haemodynamic appearance depends on the degree of renal injury and any associated injuries; there may be flank bruising and tenderness, gross or microscopic haematuria. The passing of clots is particularly suggestive of large bleeding from the upper urinary tract.
All patients with gross haematuria warrant further investigation. Patients with microscopic haematuria only warrant further investigation in the following settings:
- penetrating injury
- blunt injury with shock including transient hypotension
- high impact trauma
Computed tomography is the preferred method of evaluating renal trauma (Fig. 10.2). Although a normal intravenous pyelogram almost excludes serious renal injury, an abnormal study is inadequate to define the degree of renal trauma. CT gives accurate staging information on renal trauma and has the added advantage of assisting with the diagnosis of any other intraabdominal injuries. CT detects extravasation of contrast from the urinary tract with great sensitivity, and gives a more precise demonstration of blood flow to the renal parenchyma. The role of angiography in renal trauma is controversial. Selective renal angiography defines any areas of ischaemia, and will diagnose injuries to the renal artery and its main branches. Therapeutic embolization can be carried out at time of angiogram to stop bleeding arteries or arterio-venous fistula. Angiography should only be considered in patient adequately stabilized otherwise laparotomy and open exploration of the injured kidney is more appropriate.
Management may be operative or expectant. The presence and condition of contra-lateral kidney is important and can be easily assessed on IVP or CT scan. The ultimate goal of treatment should be patient safety and preservation of renal function, with the lowest complication rate. In the stable patient with a “minor” renal injury on CT scan and no associated nonrenal injuries, it is safe to manage conservatively. This pertains to 80-85% of all patients with renal trauma. Conservative management includes strict bed rest, with gradual mobilization if the patient remains stable and when macroscopic haematuria has cleared. The patient should be observed for haemodynamic changes and the abdomen examined regularly. If an expanding mass is observed or the patient becomes compromised exploration should be undertaken. Computed tomography surveillance, coupled with percutaneous or endoscopic interventions when appropriate (e.g. drainage of fluid collections) allows selected patients with major renal injuries to be managed nonoperatively, with less morbidity and a lower rate of nephrectomy (Mansi and Alkhudar 1997). Blood pressure surveillance every 3 to 6 months should continue for five years, as up to 10% of patients will develop hypertension following renal trauma.
Indications for urgent exploration are penetrating injuries or haemodynamic instability; a patient undergoing laparotomy for another reason may warrant exploration of the retroperitoneum if a pulsatile or expanding haematoma is observed. Blunt renal injuries should be explored if there is disruption with a significant devascularized segment, major urinary extravasation or in the case of renal pedicle injuries. Associated injuries should not affect one’s decision regarding management of the renal injury; reconstruction or repair is safe in the face of colonic or pancreatic injury (Wessels and McAnich 1996, Rosen and McAnich 1994).
Surgical exploration is best preformed via a midline approach, which enables complete examination of all abdominal organs including the kidneys. The renal vessels should be controlled before approaching the kidney in case bleeding should occur upon release of the fascial covering of the kidney. This can be achieved by exposing the aorta with an incision of the retroperitoneum between the inferior mesenteric vein and duodeno-jejunal flexure. Simple lacerations may be repaired with absorbable suture after debridement, and should be drained. Exposed defects in the collecting system or parenchymal vessels should also be oversewn with fine absorbable suture before reflecting the capsule over bare parenchyma. If closure of the capsule is not possible, the area may be covered with free peritoneum, omentum or a piece of synthetic mesh. Drainage should be provided with a closed suction drain and broad-spectrum antibiotic prophylaxis commenced. Nephrectomy should be reserved for unstable patients with persistent bleeding or severe injuries to the vascular pedicle.
In the case of children, the kidney is far more prone to injury from blunt trauma due to its intraabdominal location. Indeed the kidney is the most frequently injured abdominal organ in children. Radiological evaluation should not be reserved for unstable patients, and the degree of haematuria is an unreliable predictor of renal injury (Abou-Jaoude et al. 1996). Therefore all patients with haematuria (including microscopic haematuria) or deceleration injuries should have further radiographic assessment, with either CT or renal tract ultrasound. The indications for operative and conservative management are the same as for adults.
Key points
Ureteral injury
Isolated trauma to the ureter is uncommon because of its retroperitoneal location and its mobility.
There are three major types of injury:
- penetrating
- blunt
- iatrogenic
Penetrating injuries and surgical mishaps are by far the most common cause of ureteric injury. Blunt injuries are extremely rare, but may occur in association with a pelvic fracture. The incidence of iatrogenic ureteral injuries following gynaecologic surgical procedures is estimated at 2.5%, with a much higher incidence in abdominal approaches than vaginal (Mariotti et al. 1997). Colorectal operations, as well as vascular and endo-urological surgery can also result in ureteric injuries.
Clinical presentation varies with aetiology. In the trauma setting, penetrating injuries to the flank with or without haematuria may herald a ureteric injury. Alternatively the patient with an iatrogenic ureteric injury which was not recognized intraopertively will have a delayed presentation of flank pain, fever and leucocytosis. In either scenario imaging of the urinary tract with either CT or IVP should assist in making the diagnosis.
A number of factors determine appropriate management of a ureteric injury:
1. The site of the injury ( i.e. proximal, middle or distal third ),
2. Co-existing injuries and illnesses
3. Time taken for the injury to be recognized
4. Mechanism of injury.
5. Presence of normal contra-lateral kidney
6. Bladder mobility
More than 90% of penetrating ureteral injuries are associated with other abdominal injuries. Simultaneous colonic injury is associated with a poor outcome in patients undergoing ureteral anastomosis for penetrating trauma (Velmahos et al. 1996). Early recognition of iatrogenic ureteral injury has been shown to improve outcome. Primary repair is not possible if there has been a delay in diagnosis and secondary infection or ureteral necrosis has occurred.
Management is aimed at providing an anastomosis which is tension-free and viable. Urinary drainage with ureteric stent or bladder catheter should be continued for at least three weeks. Urinary diversion by nephrostomy and delayed repair is indicated when the patient is haemodynamically unstable, in patients with multiple injuries (especially bowel), or in the presence of sepsis.
Distal injuries should be managed with ureteroneocystotomy. Mid-ureteric injuries should be considered for primary repair or ureteroureterostomy if the diagnosis has been made promptly. After debridement the ureteric ends are spatulated and then repaired. Care must be taken to preserve the blood supply to the anastomosis. A double-J stent should be placed across the repair and adequate drainage permitted outside the ureter.
In the case of destruction of a segment of ureter, a few options are available. Mobilization of the kidney or bladder (eg. the Boari flap) may allow sufficient length for a primary repair. Secondly, a delayed reconstruction with an interposed segment of ileum has been employed with good results. Transverse ureteroureterostomy has a high complication rate, and nephrectomy should be only be considered if there is a normal contra-lateral kidney. Auto-transplant can be considered if expertise is available.
Key points
- Penetrating injuries and surgical mishaps are by far the most common cause of ureteric injury
Bladder trauma
Bladder injuries are classified into four major groups:
1. Bladder contusion
2. Extraperitoneal bladder rupture
3. Intraperitoneal bladder rupture
4. Combined intra- and extraperitoneal bladder rupture
The distinguishing feature of bladder contusion is that there is no urinary extravasation. Intraperitoneal rupture is may be caused by a blunt or penetrating injury, including motor vehicle accidents, an abdominal blow, gunshot or stab wound. A history of alcohol consumption prior to injury should raise clinical suspicion. Always consider a bladder injury in the hotel patron who has been assaulted and presents with abdominal pain and difficulty voiding. The diuretic effect of alcohol increases bladder volume and gives it a more abdominal position, where it is less protected by the bony pelvis. On the other hand, extraperitoneal rupture is normally associated with pelvic fractures with sharp fragment penetrating the bladder wall.
Gross haematuria is the most important finding in patients with a bladder rupture; in addition, most patients will complain of suprapubic pain; some patients complain of difficulty voiding. Examination reveals tenderness in the lower abdomen. It is important to examine the bony pelvis for instability or tenderness, and the genitalia and perineum for any associated injuries.
Urgent cystogram should be performed to confirm the diagnosis. Particular attention should be paid to whether the contrast tracks into the peritoneal cavity (Fig 10.3). The contrast material is best delivered by gravity and small leakage often seen only after the contrast has drained. More than 250 mL of contrast material is recommended to distend the bladder sufficiently to demonstrate a perforation.
Management depends largely on whether the rupture has occurred intra- or extraperitoneally, and the presence of any associated abdominal or pelvic injuries. All patients should be on appropriate broad spectrum antibiotic cover to prevent septic complications.
Extraperitoneal rupture may be managed by catheter drainage for a minimum of two weeks, then a follow up cystogram. Continuous unobstructed bladder drainage either by indwelling urethral catheter or superpubic catheter is absolutely essential and if this cannot be achieved the patient should undergo exploration, repair and formal tube drainage.
Intraperitoneal or combined intra- and extraperitoneal ruptures should be explored through a laparotomy, with primary repair of the bladder, suprapubic tube cystostomy and drainage. The suprapubic catheter is removed at two weeks if the patient is voiding well and repeat cystogram is normal. Similarly, if a patient requires laparotomy for any other reason, the bladder should be repaired at that time.
Urethral trauma
Traumatic injuries to the urethra are traditionally classified anatomically as anterior or posterior. Colapinto and McCallum (1977) devised a classification system based on the findings of retrograde urethrography. A modified system was recently proposed by Goldman et al. (1997) (Table 10.1).
Although urethral injuries are much less common in women than men, they can occur in association with pelvic fractures. The short length of the female urethra and its lack of attachment to the pubis makes it less prone to injury.
Posterior urethral disruption
The posterior urethra is the segment proximal to and including the area of the external urinary sphincter. Disruption of the posterior urethra is a devastating injury which carries a high morbidity rate. Trauma to the posterior urethra is normally associated with extreme blunt trauma to the lower abdomen and pelvis, along with fractures to the pelvis (especially fractures through the ilium or pubic rami). Lower urinary tract injuries occur in up to 25% of patients with pelvic ring disruptions.
Blood at the external urethral meatus is the cardinal sign of urethral injury. Blood may also be present at the urethral meatus of females with urethral trauma, but is often mistaken for vaginal bleeding. Rectal examination of the male patient with a posterior urethral injury may reveal a high riding prostate. Voiding may be difficult or impossible, however the patient who voids is not necessarily clear of urethral injury. Indeed it is impossible to exclude posterior urethral injury on the basis of clinical findings alone. A patient who is suspected of having a urethral injury should not be catheterized until such an injury has been excluded by urethrogram, otherwise there is a high risk of converting a partial tear into a more complex injury or introducing infection into a periurethral haematoma.
Radiologic evaluation of urethral injuries consists of retrograde urethrography, performed by injecting 50 mL of water-soluble contrast through a catheter-tip syringe with screening X-ray. If a urethral catheter has already been passed and is working, the study is performed through a smaller catheter introduced alongside the Foley catheter. Extravasation of contrast material reveals the level of the injury (Fig. 10.4).
Management of posterior urethral injuries is somewhat controversial. Although there has been renewed interest in early repair (endoscopically assisted), most authors favour delayed urethroplasty at least 3 to 6 months after the injury, when the haematoma and inflammation has resolved. At the time of the injury a large-bore suprapubic catheter is inserted operatively and antibiotic prophylaxis commenced. Stricture formation occurs in 95% of these patients, but this is corrected at the time of reconstruction. Realignment of the urethra and careful positioning of a urethral catheter at the time of injury will reduce the rate of stricture formation and may make delayed repair an easier undertaking. The other major long-term complications are urinary incontinence, which occurs in 10 to 15% of patients, and impotence, occurring in up to 50%. Although primary realignment does not improve the complication rate, it has the advantage of earlier removal of the suprapubic catheter.
Anterior urethral rupture
Trauma to the anterior urethra is more common than posterior urethral trauma, and most often result from “straddle” type injuries to the perineum. Anterior urethral injury may also occur in association with a penetrating injury to the penis. Clinical features of difficulty voiding and blood at the urethral meatus are still present, but in addition there may be evidence of urinary extravasation. The extent of extravasation depends on the integrity of Buck’s fascia; if this is disrupted, urine and blood may track along Collie’s and Scarpa’s fascia into the perineum (“butterfly haematoma”) and abdominal wall, limited only by its fusion with the fascia lata of the thigh and the coracoclavicular fascia in the neck.
Retrograde urethrography confirms the diagnosis. Blunt injuries are best managed with suprapubic catheterization and delayed reconstruction. Early exploration and debridement is indicated for penetrating injuries; depending on the severity of the injury, primary repair over a Silastic catheter may be possible. The catheter is maintained for 2 to 3 weeks after primary repair, and voiding cystourethrogram performed after removal.
Iatrogenic injury
Traumatic catheterizations are an unfortunately common occurrence in the hospital setting, resulting from either improper technique, anatomical difficulties (eg. prostatic hyperplasia) or a combination of these. The use of urethral catheter introducers and suprapubic catheters should be reserved for experienced medical staff only (Figure 10.4). The use of portable bladder ultrasound to measure bladder residuals provides a noninvasive alternative to urethral catheterization.
Key points
- Traumatic catheterizations are an unfortunately common occurrence in the hospital setting
A Genital injuries
B Penile trauma
i. Degloving injuries
This usually follows an accident with farming or industrial machinery. Careful examination of the penis under anaesthetic reveals the extent of skin which has been avulsed and its viability. Injuries are classified as complete or partial avulsions.
It is important to remove any clothing or other foreign material which may contaminate the wound. Any remaining distal penile skin in a partial avulsion should be debrided as far as the coronal sulcus prior to skin graft. Depending on the degree of contamination delayed grafting with split thickness skin (to allow expansion during erection) is ideal.
ii. Amputation
This is usually a self inflicted injury by a psychotic patient, or less commonly the result of an assault by a jilted lover. Principles of storage of the severed part are the same as for any amputation, namely cleaned with sterile saline, wrapped and kept cool (not on ice). Bleeding from the penile stump should be controlled with direct pressure rather than a tourniquet. The patient should be transferred to an appropriate centre with a microsurgical team; if such a facility is unavailable, reapproximation of the corpora and urethra frequently results in a successful outcome. The most important factor in survival of the penis is re-establishment of venous drainage. Most patients recover with reasonable erectile function and sensation.
Key points
- This is usually a self inflicted injury by a psychotic patient
iii. Penile fracture
A rare injury usually caused by vigorous intercourse with the partner in the dominant position. The patient gives a history of sudden forceful bending of the erect penis during coitus, accompanied by pain and loss of erection. The patient will occasionally hear a loud "crack". Urethral injury occurs in about 20% of cases. Examination reveals a swollen and bruised organ with deviation away from the injured side. In patients whose presentation is delayed, the organ is said to resemble an eggplant due to the amount of swelling and bruising.
Management consists of early primary repair of the disrupted corpus, to maximize chance of maintaining erectile function, and the urethral injury if present. Repeated subclinical penile fracturing is one of many theories for the pathogenesis of Peyronies disease.
Scrotal trauma
Penetrating scrotal injury may be associated with a degloving injury to the penis or occur as an isolated event. Management varies with the depth of trauma and the surface area involved. Lacerations which breach the dartos layer should be explored to exclude underlying testicular injury.
Degloving injury where testes are on view requires subcutaneous placement of the testes in the thigh temporarily or coverage with perineal flaps or skin graft. In contaminated wounds it is advisable to dress the testes with wet dressings initially until an area of granulation tissue has formed, before embarking on a definitive procedure. Orchiectomy is avoided if possible.
Key points
- Lacerations which breach the dartos layer should be explored to exclude underlying testicular injury
Testicular trauma
Penetrating injuries are normally associated with significant scrotal injury, and will be discovered during operative exploration. Laceration through the tunica albuginea is managed by thorough debridement, irrigation and drainage; the tunica albuginea may be closed primarily.
Blunt trauma to the testis should be assessed with ultrasound; exploration is often necessary if ultrasound is noncontributory and clinical suspicion of testicular rupture is high. This will enable the surgeon to exclude testicular torsion as a cause of pain. If an haematocoele is evacuated a Penrose drain should be placed and the scrotum closed primarily. A supportive dressing or jock-strap prevents haematoma formation and reduces pain.
Female genital injuries
Urologic and rectal injury should be considered in all female patients presenting with blunt or penetrating trauma to the perineum. The incidence of associated injury to the urinary tract has been reported as up to 30% (Goldman et al. 1998). Minor cutaneous injuries may be treated locally with primary repair but larger wounds may require grafting. Temporary faecal or urinary diversion should be considered to prevent wound contamination.
Clinical examination of traumatic injuries to the female external genitalia in children is notoriously inaccurate. A study comparing the findings on preoperative evaluation with those on examination under anaesthetic (EUA) found that over 70% of patients had more serious injuries than appreciated preoperatively (Lynch et al. 1995). Assault must always be considered as a cause for genital injury and appropriate referrals made.
Key points
- Urologic and rectal injury should be considered in all female patients presenting with blunt or penetrating trauma to the perineum
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