Fecal incontinence

　　1. Congenital anal development malformation

　　(1) Developmental defects of the nervous system: congenital lumbar sacral meningocele or spina bifida can be accompanied by anal incontinence. The patient's external anal sphincter and puborectalis muscle lose normal neural control and have no contraction function, remaining in a relaxed state. Moreover, as both the sensory and motor systems are affected, the rectal mucosa lacks a sense of distension when the rectum is filled with feces, cannot induce the desire to defecate or initiate defecation, and feces in the rectum are excreted at any time. Such children often have urinary incontinence as well.

　　(2) Anal and rectal malformations: both the anal and rectal structures and pelvic structures have changed, and the higher the rectal blind end, the more obvious and complex the changes are. In high-grade malformations, the rectal blind end is located above the pelvic diaphragm, with the puborectalis muscle shortened and significantly shifted upward and forward; the internal sphincter is absent or only in a rudimentary state; the external sphincter is mostly in a relaxed state, filled with fatty tissue, and the muscle fibers are abnormally disordered. The etiology is mainly related to defects in sensory and motor nerve tissue structures associated with malformations, and also has a clear relationship with surgical injury and surgical errors.

　　2. Trauma

　　Due to trauma that has damaged the anal and rectal ring, the anal sphincter has lost its sphincter function, leading to fecal incontinence. This includes injuries such as punctures, cuts, burns, frostbite, and lacerations (mainly perineal tears during childbirth), as well as injuries from anal and rectal surgeries such as fistula, hemorrhoids, rectal prolapse, and rectal cancer, which damage the anal sphincter and cause fecal incontinence.

　　3. Neurological disorders

　　Commonly seen in brain trauma, brain tumors, cerebral infarction, spinal cord tumors, spinal tuberculosis, and马尾神经损伤, which can all lead to fecal incontinence.

　　4. Anal and rectal diseases

　　The most common is anal and rectal tumors; such as rectal cancer, anal canal cancer, Crohn's disease involving the anal canal and rectum and affecting the anal sphincter muscle, or ulcerative colitis causing anal inflammation due to long-term diarrhea, or anal relaxation caused by rectal prolapse, as well as severe scars around the anus affecting the anal sphincter muscle, leading to incomplete anal closure can all cause fecal incontinence.

　　Fecal incontinence can cause various complications, the most common being skin inflammation around the perineum and sacral tail, and pressure ulcers. Fecal incontinence has an incidence rate of 46% to 54% in the elderly, critically ill patients, and bedridden patients. Due to the stimulation of feces, the perineal skin is often in a moist and metabolite-attacking state, making it prone to redness, swelling, ulceration, and pain. Skin ulcers can extend deep into the muscle layer or to the scrotum, labia, inguinal area, etc., causing retrograde infection through the urethral orifice and vaginal orifice, not only increasing the patient's suffering but also bringing difficulties to clinical nursing work. Due to frequent fecal stimulation, perianal skin can develop erosion, itching, ulcers, and pain, and some patients may restrict their diet to reduce feces, leading to weight loss and weight loss.

　　Inability to control the excretion of feces and gas leads to frequent moisture in the perineum and feces soiling clothing. In complete incontinence, feces can be excreted at any time; during coughing, walking, squatting, and sleeping, there is often a discharge of feces and mucus from the anus. In incomplete incontinence, although dry feces can be controlled, diarrhea cannot be controlled. Only when concentrating on controlling the anus can feces be prevented from flowing out.

　　1. Develop good defecation habits and defecate at regular times. It is best to defecate after waking up in the morning, do not stay in the toilet for too long, and get up immediately after defecating. Abandon bad habits such as reading books or newspapers while defecating.

　　2. Treat any discomfort around the anus promptly. Because the anus has physiological and pathological characteristics, the surrounding area has many folds, sebaceous glands, and sweat glands. Additionally, the feces excreted contain a large number of bacteria, making it easy to cause infection. Therefore, if there is any discomfort or pain around the anus, treatment should be sought promptly to prevent the condition from worsening.

　　3. Maintain smooth defecation. Drink plenty of water every day, especially a large glass of warm water upon waking. Pay attention to adjusting your diet, eating more vegetables and fruits rich in fiber. Avoid drinking alcohol in large quantities and not eating spicy, dry, and irritating foods.

　　4. Choose underwear and toilet paper scientifically. Underwear should be made of soft and thin cotton fabric, not coarse cloth or synthetic materials. Toilet paper should be thin, soft, and have small, even folds. Do not use waste newspapers or waste paper that has been written on with a ballpoint pen, as the ink can cause perianal diseases due to long-term irritation.

　　5. Do not ignore anal cleaning. Wash the anus twice a day, once immediately after defecation and once before going to bed to prevent soiling of underwear.

　　6. Regularly take sitz baths. Sitz bath is a good method for anal health care and treatment. For mild anal disorders, sitz bath can have a significant effect. The water temperature should not be too hot to avoid burns, but also not too cold to be ineffective. The sitz bath time should generally not be less than 20 to 30 minutes. During this period, hot water can be added appropriately to promote perianal blood circulation and accelerate the absorption of inflammation.

　　7. Pay attention to doing anal contraction exercises, it is best to do them twice a day, morning and evening. The perineum should be contracted and relaxed during the exercise, 50 to 100 times each time, which can promote the return of venous blood near the anal canal and rectum.

　　1. Rectal examination:The examiner feels that the anus is relaxed without a sense of urgency. When the patient is asked to contract the anus, the anal sphincter contraction is not obvious or completely without contraction. If the patient has a history of anal injury, scars can be palpated. Some patients can feel a contraction on one side of the anal canal while the other side has no contraction. Pay attention to whether there are masses, tenderness, etc., within the anal canal and rectum. After the finger is withdrawn from the anus, observe whether the finger glove is sticky or bloody.

　　2. Endoscopic examination:Observe whether there are deformities, scars, erosion, ulcers in the anal canal skin and rectal mucosa, whether there is congestion, edema in the rectal mucosa, rectal polyps, rectal cancer, anal cancer, and anal-rectal cancer, etc.

　　3. Defecation radiography examination:By observing the dynamic changes during efforts to defecate, anal contraction, and other activities, the function of the anal sphincter can be understood. If barium灌入rectum can be retained by anal contraction, it indicates that the anal sphincter has certain function; if barium灌入rectum is involuntarily discharged, it indicates fecal incontinence.

　　4. Anal canal and rectum pressure measurement:Patients with fecal incontinence show a decrease in pressure within the anal canal and rectum, a decrease in frequency or disappearance; a decrease in anal canal systolic pressure; the disappearance of the rectal anal canal inhibitory reflex, such as patients with ulcerative colitis causing fecal incontinence show a significant decrease in rectal compliance.

　　5. Rectal sensation measurement:It involves inserting a 4cm×6cm balloon with a catheter into the rectum, then injecting water or air into the balloon. The normal rectal sensation threshold is 45ml±5ml. For patients with neurogenic fecal incontinence, the rectal sensation threshold disappears.

　　6. Balloon expulsion test:If the rectal sensation is dull, the normal capacity cannot cause a defecation reflex, and the balloon cannot be expelled. This examination can be used to judge whether the rectal sensation is normal and to judge the function of the anal sphincter. If the anal sphincter is damaged and has no sphincter function, the balloon can slip out of the anus spontaneously, or it can be expelled by slightly increasing abdominal pressure.

　　7. Pelvic floor electromyography examinationThis examination can understand the location and extent of the anal sphincter defect.

　　8. Transrectal endoscopic ultrasound examination:Transrectal endoscopic ultrasound can clearly display the various layers of the anal canal and rectum, the internal anal sphincter and its surrounding tissue structure, which can assist in the diagnosis of anal incontinence, such as observing whether the internal anal sphincter is intact, whether the external anal sphincter has a defect, and the location and extent of the defect. This examination not only assists in diagnosis but also provides a certain basis for the selection of surgical incisions.

　　Patients with fecal incontinence should improve their diet structure, prefer high-protein, high-calorie, easy-to-digest, and high-fiber foods to facilitate defecation. Increase the content of dietary fiber in the diet, with an average daily supply of 6.8g. Dietary fiber is not absorbed by the body, but it can increase the volume of feces, stimulate peristalsis, help restore intestinal function, strengthen the regularity of defecation, and effectively improve the condition of fecal incontinence.

　　1. Non-surgical Treatment

　　(1) Dietary Regulation: To treat anal and rectal inflammation, make stools formed, avoid diarrhea and constipation, and eliminate the discomfort caused by the stimulation of anal and rectal inflammation. Common methods include eating more foods high in fiber and nutrition, and avoiding刺激性 foods. If there is inflammation in the anal and rectum, antibiotics can be taken according to symptoms. If there is inflammation around the anal canal skin, it should be kept clean and dry or medicated ointment should be applied.

　　(2) Anal Sphincter Exercise: The method is to ask the patient to contract the anal sphincter (levator ani) about 500 times a day, holding each contraction for several seconds, which can enhance the function of the anal sphincter.

　　(3) Stimulating the contraction of the anal sphincter: For patients with neurogenic anal incontinence, electrical stimulation therapy and acupuncture therapy can be adopted. Electrical stimulation therapy involves placing stimulation electrodes inside the external sphincter, using electrical stimulation to make the anal sphincter and levator ani muscles contract regularly, which can improve the condition of some patients with anal incontinence. Acupuncture therapy is a traditional Chinese medicine therapy, and some patients can also achieve good effects, with commonly used acupoints including Changqiang, Baihui, Chengshan, etc.

　　2. Surgical Treatment

　　Surgical treatment for anal incontinence is mainly used for anal canal sphincter injury and anal incontinence after congenital high anal atresia surgery.

　　(1) Anal Sphincter Repair: Suitable for patients with anal canal sphincter injury caused by trauma. Generally, it is repaired within 3-12 months after the injury, as prolonged time may cause atrophy of the sphincter due to disuse.

　　(2) Anal Canal Anterior Sphincter Plication: Suitable for patients with sphincter relaxation.

　　(3) Vaginal Sphincter Plication: Suitable for patients with sphincter relaxation.

　　(4) Parks Anal Canal Posterior Pelvic Floor Repair: Suitable for patients with severe neurogenic anal incontinence and rectal prolapse after fixation surgery who still have relatively severe anal incontinence.