Bladder injury

　　1. Direct violence:Most bladder injuries occur when the bladder is distended, with the bladder elevated above the pubic bone, and direct violence is applied to the lower abdomen, causing bladder injury, such as kick injuries, punch injuries, and collision injuries. Due to the bladder being filled, the external force is evenly transmitted to all parts. According to fluid mechanics, the weakest part of the bladder is most often the top, which is covered by the peritoneum, forming a rupture. The rupture here is mostly an intraperitoneal bladder rupture. Urine then flows into the peritoneal cavity, forming a urinary peritonitis, and the patient experiences severe and unbearable abdominal pain. I once encountered a patient with urinary retention who, after catheterization, found the flow rate of urine too slow, massaged and applied pressure to the pubic bone with his hand. The patient suddenly felt severe abdominal pain and the previously distended bladder suddenly disappeared. The surgery confirmed a rupture of the bladder top, with urine flowing into the peritoneal cavity.

　　2. Indirect violence:It often occurs during pelvic fractures, accounting for about 80%. Sometimes it is often a complex injury, which can be accompanied by injury to other organs. Such as traffic accidents, earthquakes, car accidents, high-altitude falls, crush injuries, war injuries, industrial injuries, etc. During pelvic fractures, the fractured ends or floating bone fragments can pierce the bladder, at this time, the bladder injury is mostly extraperitoneal bladder rupture, and the rupture site is mostly at the bottom of the bladder. There may also be subsequent urethral rupture or abdominal organ and blood vessel injury, pelvic粉碎骨折, with urinary extravasation, severe hemorrhage, shock, and other symptoms. There may also be intraperitoneal and extraperitoneal bladder rupture (mixed type, complex injury), which is very serious. For example, a patient fell from a tractor and caused the pubic ramus and ischial ramus fractures, resulting in a rupture of the anterior bladder wall and urinary extravasation. After rescue, bladder repair, and urinary extravasation drainage, the recovery was smooth and the patient was discharged from the hospital. In daily life, bladder injury caused by indirect violence is the most common.

　　3. Firearm and sharp object injury:It is often due to war or fighting, usually with open-type bladder injury, and can also be accompanied by injury to other organs.

　　4. Iatrogenic bladder injury:Due to the examination of the bladder in recent years, various instrumental operations such as cystoscopy, bladder lithotripsy, and various operations and treatments inside the bladder through the urethra, such as electrocoagulation and electrocision, can cause bladder perforation. Most of them are due to bladder lesions that require cystoscopy, and some indications are not properly controlled, such as when the bladder capacity is too small, the cystoscope can cause bladder perforation when inserted. During the electrocision of bladder tumors, if it is too deep or the observation is not satisfactory, and the bladder is in an expanded state, the bladder wall is thin, and it is very easy to cause bladder perforation during electrocision, such as causing intraperitoneal bladder perforation at the top, and extraperitoneal bladder rupture (perforation) at other locations. The injection of corrosive agents, chemical drugs, or hardening agents into the bladder can also cause bladder injury. For example, pelvic surgery, gynecological surgery, obstetric surgery, rectal surgery, and hernia repair surgery can all cause bladder injury. During labor, when the fetal head has entered the pelvis, the second stage of labor is long, and there is pressure on the bladder, it is often possible to cause the soft tissues such as the bladder trigone, vaginal wall, and urethra to be compressed, leading to ischemia and hypoxia and necrosis, and eventually forming a vesicovaginal fistula or urethrovaginal fistula. Especially when there is dystocia and urinary retention, at this time, due to the expansion of the bladder, the bladder wall is thin and it is more susceptible to pressure, causing ischemic necrosis and forming a fistula. This kind of 'fistula' generally does not occur immediately after delivery, but occurs one week or even longer after delivery.

　　When the bladder communicates with adjacent organs to form a urinary fistula, urine can flow out from the rectum, vagina, or abdominal wound, often accompanied by urinary tract infections.

　　Bladder rupture is a relatively serious injury. Intraperitoneal rupture causes urinogenic peritonitis and is often difficult to distinguish from injuries to abdominal hollow organs. When the diagnosis is suspicious and the condition is relatively serious, an emergency abdominal exploration should be performed without delay. Once bladder rupture is found, intraperitoneal rupture is repaired through the abdomen, extraperitoneal rupture is repaired through the bladder, and bladder fistula is performed. Drainage tubes are placed around the abdomen or bladder to drain urine exudation. The prognosis is good. If perforation is caused by cavity instruments, intraperitoneal rupture should be immediately repaired through laparotomy, and bladder fistula should be performed. Extraperitoneal rupture can be left with a catheter to continuously drain the bladder. The amount of normal saline infused into the peritoneal space around the bladder can be absorbed spontaneously. A large amount should be drained by cutting the catheter.

　　Bladder injury often occurs with the injury of pelvic or abdominal organs, which belongs to complex injury. It is not easy to obtain an immediate diagnosis at one time. It is often overlooked due to the focus on abdominal important organs or blood vessels, pelvic injuries, and ignoring the possibility of bladder injury. Especially for patients with intraperitoneal type bladder rupture, if the diagnosis cannot be determined, the incidence of peritonitis will increase significantly, and the mortality rate will also increase accordingly. Statistics show that it is more than 10%.

　　First, medical history

　　Patients with bladder injury often have a clear history of trauma, such as pelvic or lower abdominal violence or piercing injury, abdominal pain after injury, a desire to urinate but unable to urinate or only able to urinate a small amount of hematuria. In severe cases, patients may develop shock. Spontaneous bladder rupture without a clear history of trauma, but with a history of primary bladder disease or lower urinary tract obstruction, and mostly occurs under conditions where abdominal pressure rises sharply, such as straining to urinate, defecate, etc. Iatrogenic bladder injury will also have corresponding medical history.

　　Second, physical examination

　　1. When the bladder is found to be empty and only a small amount of blood-containing urine during catheterization, it should be considered that there may be bladder rupture with urine exudation. A certain amount of disinfected normal saline can be injected, and then retracted after a moment. If the amount of fluid withdrawn is less than the amount injected, bladder rupture and urine exudation should be suspected.

　　2. After catheterization,造影剂is injected into the bladder through the catheter to understand whether there is bladder rupture, urine exudation, and its exudation site. Sometimes, it can even be found that the catheter has passed through the bladder rupture into the peritoneal cavity, thereby making a clear diagnosis.

　　3. Excretory urography: If the condition allows, excretory urography can be performed to display the structure and function of the urinary tract.

　　4. Abdominal puncture: If there is an abdominal hydroperitoneum, abdominal puncture can be performed. If a large amount of blood-containing fluid is withdrawn, the urea nitrogen and creatinine content can be measured. If they are higher than the blood creatinine and urea nitrogen, it may be urine exudation.

　　Prevention should be specific according to the primary disease. Common causes are mostly traumatic, such as accidental accidents, violent beatings, or sharp instrument cuts causing bladder injury. Therefore, attention should be paid to safe driving to avoid accidents, calm behavior to avoid violent conflicts, and avoid trauma.

　　1. Bladder irrigation test

　　During catheterization, an empty bladder or only a small amount of hematuria is found. A certain amount of sterile normal saline (100-150ml) is injected into the bladder through the catheter, and then wait for a moment before withdrawing; if the amount of fluid withdrawn is significantly less or more than the amount injected, it indicates the possibility of bladder rupture.

　　2. Bladder urography

　　Inject 300-400ml of contrast agent into the bladder, and take films in the anteroposterior position, oblique position, or when the contrast agent is excreted. According to the leakage of the contrast agent, the diagnosis of bladder rupture and the type and degree of rupture can be clearly determined.

　　3. Cystoscopy

　　It can clearly diagnose bladder contusion.

　　4. B-ultrasound examination

　　It can detect the shape of the bladder. If there is no bladder rupture, a complete bladder can be detected. If there is a bladder rupture, the bladder cannot be filled, and the shape of the bladder will also change. If combined with the water injection test, it can detect whether the bladder can be filled and where the liquid flows, which will also be helpful for determining the type of bladder injury. When there is 'ascites' in the abdominal cavity, it is also helpful for determining intraperitoneal bladder rupture.

　　5. Abdominal puncture fluid examination

　　Patients with signs of peritoneal (water) inflammation or those suspected of having intraperitoneal bladder rupture through the above bladder urography can undergo peritoneal puncture. If the patient has significant abdominal distension, puncture should be done with caution to avoid injury to the intestines. When fluid is obtained from puncture, it can be subjected to routine examination or the content of urea nitrogen can be measured (it can be compared with blood and urine urea nitrogen to determine whether urine has流入腹腔).

　　6. Computerized X-ray tomography (CT) examination

　　CT examination has the characteristics of clear images and high density resolution. It can clearly show the contours, structures, and injuries (lesions) of various organs in the brain, chest, abdomen, and pelvic cavity. It can accurately and stereoscopically judge the shape, size, location, and relationship with adjacent organs. Especially in cases of multiple organ injuries, it can make a comprehensive and timely diagnosis. CT examination is a safe and non-invasive examination. According to the patient's condition, the examination site can be chosen, such as scanning the liver and spleen if there is a suspicion of liver and spleen injury, and performing renal and bladder examination if there is urinary tract injury. Generally, the bladder should be examined when it is full. If there is no urine, a catheter can be inserted to inject water for examination or contrast agent injection examination. It can observe the shape of the bladder, the surrounding structures, and whether there is urine extravasation. CT examination can distinguish the density of tissue structures and can also make a judgment on the range of urine leakage. Generally, in cases of only lower abdominal injury, in addition to the pelvic or abdominal plain film, CT examination is not performed. If there is still doubt about the above bladder urography, CT examination can be considered.

　　7. Magnetic Resonance Imaging (MRI) examination

　　The amount of information provided by MRI is not only greater than that of other imaging techniques in medical imaging, but MRI does not have X-ray radiation. The parameters involved in imaging are the proton density and the relaxation time constant (T1, T2) of the hydrogen atom nuclei in human tissues, that is, the movement characteristics of protons. MRI still belongs to computer imaging, and all imaging is tomographic images.

　　8. Cystocentesis

　　If there is no urethral injury, the catheter can be smoothly inserted into the bladder. If the patient cannot urinate and the urine discharged is hematuria, it should be further understood whether there is a bladder rupture. The catheter can be retained for injection test. If the amount of withdrawal is significantly less than the amount of injection, it indicates a bladder rupture.

　　9. Excretory urography

　　If there is a suspicion of upper urinary tract injury, consider using it to understand the condition of the kidneys and ureters.

　　What foods should be avoided for bladder injury:

　　1. Avoid eating chicken, chili, fish, shrimp, beef, seafood, pickles, and seasonings can only be used with vinegar, salt, monosodium glutamate (do not use other seasonings).

　　2. Avoid eating sour and spicy foods, such as strong alcohol, chili, balsamic vinegar, sour fruits, etc., drink less coffee, and eat diuretic foods such as watermelons, grapes, pineapples, celery, pears, etc.

　　I. Treatment

　　Early treatment of bladder rupture includes comprehensive therapy, prevention and treatment of shock, emergency surgery, and control of infection. Late treatment mainly involves repairing bladder fistulas and general supportive treatment.

　　1. Non-surgical treatment

　　Bladder contusion generally does not require special treatment. Advise drinking plenty of water, adequate rest, and for severe cases, urinary catheterization can be used to drain urine, and antibiotics may be administered if necessary.

　　For patients with extraperitoneal bladder rupture, there was a method of treating it with simple transurethral catheterization 50 years ago, but it was gradually forgotten due to a high incidence of complications. Since the 1970s, clinical reports have been increasing. It is generally believed that extraperitoneal bladder rupture, regardless of gender or the size of the incision and the amount of extravasation, can be treated in this way. However, in the 29 cases treated by Kotkin et al., 26% developed complications, including delayed bladder healing, urine extravasation infection, and pelvic hematoma infection with sepsis. The main reason for failure was the lack of prophylactic use of antibiotics for urinary tract infection and poor catheter drainage.

　　For this reason, some physicians suggest that strict indications should be selected when treating extraperitoneal bladder rupture with simple urine drainage, and the following matters should be noted: ① The diagnosis must be made within 12 hours; ② There is no need for surgical exploration of other associated injuries; ③ No history of urinary tract infection; ④ The incision is not large and there is no obvious bleeding; ⑤ The catheter diameter inserted should be sufficient, not less than 24F for adults, and the patency of the drainage should be maintained. If the goal is not achieved within 24-48 hours, surgery should be considered; ⑥ Closely monitor the condition, and surgery should be performed at any time if indicated; ⑦ Preventive use of broad-spectrum antibiotics, especially drugs targeting Gram-negative bacilli.

　　2. Surgical treatment

　　Surgical steps: a midline suprapubic incision is made, and the underlying fascia is sequentially incised and separated, and the rectus abdominis muscle is retracted to expose the anterior bladder space. The management of extraperitoneal and intraperitoneal bladder ruptures is as follows:

　　(1) Externally located bladder rupture is characterized by a large amount of blood and urine extravasation in the anterior bladder space. After aspiration, the anterior bladder wall is visible. The fractured pubic bone does not need to be further investigated. If fracture fragments or foreign bodies puncture the subcutaneous blood vessels or bladder, the fragments can be removed, and the bleeding vessels can be ligated to stop the bleeding. If necessary, the anterior bladder wall can be incised to explore the internal bladder and confirm the location and size of the rupture. After removing necrotic tissue, the inner mucosa of the incision must be sutured with absorbable sutures. Attention should be paid to avoid ligating the ureter during suture. If the condition is critical and the incision is near the bladder neck, making it difficult to suture carefully, there is no need to force the repair. Perform a suprapubic cystostomy and thoroughly drain the anterior bladder space, and the incision can heal spontaneously. After repairing the bladder rupture, an indwelling catheter should be left for about 1 week before removal. If there is urine extravasation in the abdominal wall, lumbar region, ischiorectal fossa, perineum, scrotum, or even the thigh, it is necessary to incise and drain thoroughly to prevent secondary infection.

　　(2) Intra-peritoneal bladder rupture, incise the peritoneum, aspirate the fluid in the abdominal cavity, explore the dome and posterior wall of the bladder to determine the incision, and at the same time, the anterior wall of the bladder can be incised below the peritoneal reflex and the internal bladder observed. After repairing the incision, if there is no injury to the abdominal viscera, the peritoneum is sutured. A high-position fistula is made on the anterior wall of the bladder, and the pre-vesical space is drained.

　　3. Late Treatment

　　Mainly the treatment of bladder fistula, which must wait until the general condition of the injured person improves and local acute inflammation subsides before it can be carried out. Long-term bladder fistula can cause serious infection and contraction of the bladder, and appropriate preventive and treatment measures should be taken. The main steps of surgery are to excise the fistula and scar tissue at the margin of the fistula, suture the fistula, and perform a high-position suprapubic bladder fistula. The colostomy should be closed only after the bladder rectal fistula is completely repaired and healed. Bladder vaginal fistula and bladder uterine fistula should be repaired, and a new fistula should be created above the pubis for the bladder, and the pre-vesical space should be drained.

　　Second, Prognosis

　　The bladder has a very strong healing ability, and complications rarely occur if treated promptly and properly. There may be urgency, frequency, or an unstable bladder in the early stages after injury, which will gradually return to normal as time goes by. Bladder infections caused by catheters can be effectively treated with appropriate antibiotics. As long as there is no obstruction in the urethra, there is rarely a urinoma after the suprapubic catheter is removed. The mortality rate of bladder injury is still relatively high. It is reported to be 15.6% to 22%, mainly due to associated injuries, and those related to bladder injury are due to delayed diagnosis and improper treatment.