Urinary extravasation

Introduction Urethral injury is more common in men, divided into open and closed, which is a common emergency in urology. Open urethral injury is mostly caused by shrapnel and sharp injury, often accompanied by scrotum, penis or perineal penetrating injury. A closed injury is a contusion, laceration, or direct injury to the intraluminal instrument. Anatomically, the male urethra is divided into the anterior and posterior segments by the urogenital tract. The anterior urethra includes a bulb and a penis, and the posterior urethra includes a prostate and a membrane. Urethral injury occurs mostly in the bulb and membrane. Improper early treatment can cause complications such as urethral stricture and urinary fistula. Urinary extravasation after urethral injury: The urethra is the most vulnerable part of the urinary system. It mainly occurs in male youth. There are very few women, only 3%. Male urethra is divided into two parts by genital warts. The anterior urethra is the cavernous urethra, especially the ball is more damaged, mainly caused by riding a cross injury. The posterior urethra is located in the pelvis, mainly caused by pelvic fractures.

Cause

(1) Causes of the disease

1 The vast majority of urethral injuries are caused by the application of transurethral instruments or the discharge of foreign bodies (such as stones). A small number of abnormal, drunk or mental patients with needles, iron wire, glass and other foreign objects inserted into the urethra and cause damage, mis-injection of certain chemical drugs such as silver nitrate, copper sulfate, carbolic acid, etc. can cause chemical burns. Transurethral resection of the urethra can cause electrical burns in the urethra.

2 urinary tract violent injury This injury is more common than intraurethral injury. Can be a through injury or a closed injury. The former is mainly seen in the battlefield, and the urethra is worn by firearms or sharp weapons. Most of the injured parts are in the ball and membrane. The cavernous body and the prostate are rare. Closed urethral injury can be seen during wartime and peacetime. The injured part of the perineum riding a cross injury or kick injury is more common in the ball and membrane urethra, and with pelvic fractures, often accompanied by prostate urethral injury.

1. Closed urethral injury: mainly caused by perineal riding and pelvic fracture.

(1) Perineal riding cross-injury: When the fall or fall falls from the height, the perineum rides across the hard object or the perineum is severely kicked. Most of the injured parts are located in the urethra of the ball, and a few can damage the urethra of the bulb. Because the ball urethra is relatively fixed under the pubic symphysis, the perineum rides over the hard object, and the ball urethra is squeezed between the hard object and the pubic symphysis, which is easy to cause injury. Such injuries generally do not involve pelvic fractures.

(2) Pelvic fractures: The most common pelvic fractures combined with urethral injuries in traffic accidents, industrial accidents or natural disasters occur in almost all parts of the posterior urethra. Posterior urethral injury caused by pelvic fractures is mostly urethral tear (break) injury caused by fracture, and a few are fractures of fracture ends. Because the pubis ligament is fixed in the lower part of the pubic symphysis, the urethra of the membrane passes through the urogenital ridge and is fixed by it. When the pelvic fracture causes the anteroposterior diameter of the pelvic ring to increase, the left and right diameters become smaller, or the anteroposterior diameter becomes smaller and the left and right diameters increase. The pubic ligament of the pubis is subjected to sharp traction and sudden displacement of the prostate, causing tearing or rupture of the junction of the prostatic urethra and the membrane urethra; or tearing of the urogenital ridge due to the fracture, causing the membrane urethra passing through it to be torn or fracture.

2. Open urethral injury: more common in sharp injuries or firearm injuries, occasionally in animal bites and horn horn stab wounds, often accompanied by damage or loss of the penis and perineum, the injury is complicated.

3. Iatrogenic injury: often caused by improper operation of the urethral instruments. Most occur in the external urethra, the ball urethra, the membrane urethra or the prostate urethra. When the urethra has lesions, especially when there is obstruction, it is more likely to occur. The degree and extent of injury may vary from mucosal contusion to urethra and even into the rectum.

According to the injury site, the urethral injury is divided into:

1 anterior urethral injury, more common in riding a cross injury, damage in the urethral ball.

2 posterior urethral injury, more common in pelvic fracture caused by urethral rupture, can be simultaneously damaged with the bladder.

(two) pathogenesis

Pathological changes after urethral injury vary with the cause of urethral injury and the extent of injury.

1. Urethral mucosal burns often cause extensive urethral stricture.

2. Urethral contusion and partial rupture can cause urethral stricture.

3. In the urethral rupture of the membrane, the proximal urethra is retracted and displaced backwards, and urinary retention occurs. If the urination is forced, urinary extravasation occurs, often accompanied by pelvic fractures.

4. The range of extravasation of urine varies with the location of the fracture

(1) When the anterior urethra ruptures, such as the deep fascia of the penis, the extravasation of the urinary tract is limited to the penis itself, which is characterized by swelling of the penis; if the deep fascia of the penis is broken and the perineal fascia is intact, the extravasation of urine will accumulate in the scrotum. This extravasation of urine can be seen when the urethral bulb is damaged.

(2) When the posterior urethra ruptures, the rupture is often above the deltoid ligament, and extravasation of urine will spread to the prostate and around the bladder, extraperitoneum, and retroperitoneum.

an examination

Related inspection

Urethral function test bladder neck elevation test urethral opening examination

The clinical manifestations of urethral injury depend on the location and extent of injury and whether or not pelvic fractures and other visceral injuries are associated. Simple urethral injury, systemic symptoms are mild, such as with pelvic fractures, can occur in shock. Its main performance is as follows.

1. Shock: Urethral injury after pelvic fracture, the incidence of shock is high, about 40%. It is generally not a shock to simply ride a cross injury.

2. Urethral hemorrhage: The anterior urethral injury has blood dripping or overflowing from the urethra.

3. Pain: There are often pain and tenderness in the area, dysuria and radiation to the penis head and perineum.

4. Difficulties in urination and urinary retention: those who have severe injuries cannot urinate after injury. A little longer after the injury, the suprapubic area can reach the inflated bladder.

5. Hematoma and ecchymosis: ecchymosis and hematoma can be seen under the skin of the cross-injury, and can be extended to the perineum, so that the skin of the scrotum and perineum is swollen and blue-purple.

6. Extravasation of urine: The location of urinary extravasation and extravasation after urethral injury depends on the extent and location of urethral injury. Urethral extravasation occurs in patients with ruptured or broken urethra and frequent urination. Urinary exudation around the bladder can cause rectal irritation and lower abdominal peritoneal irritation. If the extravasation of urine is not treated in time or secondary infection, it may lead to tissue necrosis and suppuration. In severe cases, symptoms of systemic poisoning may occur. Local infection or necrosis can form urinary fistula.

According to medical history, symptoms and signs, the diagnosis of urethral injury is not difficult. The signs of anterior urethral injury are generally more obvious, and the diagnosis is easier. The diagnosis of posterior urethral injury is more difficult.

The diagnosis of urethral injury should be based on the history of trauma, symptoms and signs, and pay attention to the following problems:

1. Determine the site of urethral injury.

2. Estimate the extent of urethral injury.

3. Whether there are other organs combined with injury, patients with urethral injury after pelvic fracture caused by severe trauma, especially shock patients should pay attention to check for other organ damage. In order to avoid missing important tissue and organ damage that threatens life.

Differential diagnosis

1. Bladder rupture: extraperitoneal bladder rupture is also often associated with pelvic fractures, but also puberulous sulcus, urinary extravasation around the bladder, dysuria, no urine and other symptoms. However, when the extraperitoneal bladder ruptures, the bladder is often not filled and is in an empty state. The catheter can be inserted smoothly through the urethra, and there is no urine or only a little hematuria after insertion. There was no prostate displacement and tenderness in the digital rectal examination. Bladder urethrography can be used to identify if necessary.

2. Urethral tumors: There are symptoms of dysuria, often accompanied by hematuria or urethral hemorrhagic secretions. However, no history of trauma, dysuria often tends to progressively worse. Palpation along the urethra or anal finger examination can reach local lumps of the urethra with tenderness. Urethral angiography or urethral cavernography can show urethral filling defects.

3. Urinary tract stones: Sudden urination and dysuria, often accompanied by frequent urination, urgency and hematuria. There may be a history of renal colic or a history of urethra, but no history of trauma. Sometimes palpation along the anterior urethra or rectal examination can reach local induration with tenderness. Urethral probing can touch foreign body sensation; X-ray examination can find urethra opaque shadow; urethroscopic examination can directly see the stone.

4. Spinal cord injury: When urinary difficulty or acute urinary retention occurs after lumbar trauma, it is sometimes necessary to distinguish it from urethral injury. In the case of spinal cord injury, in addition to symptoms of dysuria, it is often accompanied by neurological symptoms and signs, such as perineal sensation loss, anal sphincter relaxation.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.