Fecal incontinence in the elderly

　　How is fecal incontinence in the elderly caused? Briefly described as follows:

　　There are many causes of fecal incontinence, and one or more causes can lead to fecal incontinence. There are many ways to classify fecal incontinence, which can be classified according to the degree, nature, rectal sensation, and etiology of incontinence, or by TCM syndrome differentiation, but there is currently no unified classification standard, and the etiological classification is as follows:

　　1. Changes in the characteristics of feces

　　(1) Irritable bowel syndrome.

　　(2) Inflammatory bowel disease.

　　(3) Infectious diarrhea.

　　(4) Abuse of laxatives.

　　(5) Malabsorption syndrome.

　　(6) Short bowel syndrome.

　　(7) Radiation enteritis.

　　2. Abnormalities of intestinal capacity or compliance

　　(1) Inflammatory bowel disease.

　　(2) Defect in rectal capacity.

　　(3) Rectal ischemia.

　　(4) Collagen vascular disease.

　　(5) Rectal tumor.

　　(6) Extrarectal compression.

　　3. Rectal sensory abnormalities

　　(1) Neurological lesions.

　　(2) Overflow incontinence.

　　4. Abnormalities of anal or pelvic floor function

　　(1) Anatomical defect of the sphincter.

　　(2) Loss of neural control of the pelvic floor muscles.

　　(3) Congenital abnormalities.

　　The causes of elderly faecal incontinence may be due to fecal impaction, rectal sensory abnormalities, decreased anal sphincter pressure, neuromuscular dysfunction, dementia, iatrogenic factors, and so on.

　　Faecal incontinence can cause a variety of complications, the most common being perianal and sacral skin inflammation and pressure ulcers (bedsores). The incidence of faecal incontinence in the elderly, critically ill patients, and bedridden patients reaches 46.0% to 54.4%. Due to the stimulation of feces, the perianal skin is often in a moist and eroded state of metabolic products, which is prone to redness, swelling, and ulceration. Skin ulcers can extend deeply into the muscle layer or extend to the scrotum, labia, inguinal area, etc., polluting the urethral opening and vaginal opening, causing retrograde infection. This not only increases the patient's suffering but also brings difficulties to clinical nursing work. Due to frequent irritation by fecal water, the perianal skin may develop erosion, itching, ulcers, and pain, and some patients may restrict their diet to reduce feces, leading to weight loss and weight loss.

　　Faecal incontinence is more common in the elderly and usually occurs in a state of weakened physical condition, often accompanied by constipation or urinary incontinence. Faecal incontinence is more common in women than in men, and it is more common in multiparous women.

　　1. Faecal incontinence can manifest as varying degrees of control over defecation and flatus. In mild cases of incontinence, patients lose control over flatus and liquid feces, and their underwear may occasionally be soiled. In severe cases, patients also lose control over solid feces,表现为频繁排出粪便。If the patient can find the toilet quickly, they can avoid soiling their clothes. Patients with this condition often suffer from a long-term moist and unclean perianal area, which affects the quality of life and mental health due to soiling of clothes, bedding, and other items.

　　2. Physical examination may show moist and unclean perianal area, eczema, ulcer scars, perianal skin scars, anal relaxation, and sometimes rectal prolapse. Digital examination may reveal hard fecal masses or tumors, and there may be anal sphincter relaxation and extension, with reduced or absent contraction strength. A careful examination can accurately determine the areas of weak contraction, and it can also show the disappearance of anal reflexes.

　　How should elderly patients with fecal incontinence be prevented? Briefly described as follows:

　　1. Treatment of anal-rectal injury

　　The damage to anal function caused by anal-rectal injury is related to the cause and degree of the injury, therefore, timely and correct treatment of the injury is often an important link in preserving defecation function.

　　2. Treatment of anal-rectal diseases

　　When repairing and shaping the anal congenital defect, attention must be paid to the utilization of the original anal sphincter, especially the reconstruction of the anal-rectal ring, which is the key to postoperative recovery of defecation function.

　　What should elderly patients with fecal incontinence do for examinations? Briefly described as follows:

　　First, local examination

　　An anal examination can understand whether there are local factors causing fecal incontinence.

　　1. Visual examination

　　Pay attention to the presence of fecal contamination, ulcers, eczema, skin scars, mucosal prolapse, anal dilation, and other conditions.

　　2. Digital examination

　　Pay attention to the contraction force of the anal sphincter, the tension of the anal-rectal ring, and so on.

　　3. Endoscopy

　　Observe the color of the rectal mucosa, whether there are ulcers, inflammation, bleeding, tumors, stenosis, anal fistula, and so on.

　　Second, laboratory examination

　　The function of the anal and rectal function has a complex mechanism of interaction among various different factors that allow defecation at any time and maintain self-control ability, therefore, a special examination can test one aspect of this mechanism, and clinical evaluation must be comprehensively considered based on various examination results. Common diagnostic tests for evaluating pelvic floor and sphincter function include:

　　1. Anal-rectal manometry

　　Including the resting pressure of the anal internal sphincter, the maximum pressure during the voluntary contraction of the external sphincter, the perception threshold during relaxation, and the resting pressure and maximum pressure of the anus during fecal incontinence, all of which decrease.

　　2. Electromyography

　　It reflects the physiological activity of pelvic floor muscles and sphincters, and is an objective basis to understand the location and degree of nerve and muscle injury.

　　3. Defecation imaging

　　It can record the dynamic changes during defecation, and by changing the rectal angle, it can infer the state and degree of injury of the puborectalis muscle.

　　4. Normal saline enema test

　　By injecting 1500ml of normal saline into the rectum while sitting, the amount of leakage and the maximum retention volume are recorded to understand the self-control ability of defecation, and the retention volume decreases or becomes zero during fecal incontinence.

　　5. Anal ultrasound

　　It can accurately determine the location and asymmetry of anal sphincter defects, and measure the thickness of the internal anal sphincter.

　　The dietary principles for elderly patients with fecal incontinence are briefly described as follows:

　　1. Eat more foods high in fiber and rich in nutrition. Foods high in fiber can slow down the emptying of the intestines. Such foods include bananas, rice, starch, bread, potatoes, apple sauce, cheese, peanut butter, yogurt, dough, and oatmeal.

　　2. Consume an appropriate amount of dietary fiber. For many people, fiber makes stools softer, more formed, and easier to control. Fiber is found in fruits, vegetables, and grains. It is recommended to maintain a daily intake of 20-30 grams of fiber, but it should be gradually increased to allow the body to adapt. Adding too much fiber at once can cause bloating, flatulence, and even diarrhea. Similarly, too much insoluble fiber can lead to diarrhea.

　　3. Avoid eating irritant foods.

　　The following is a brief description of the treatment methods for elderly fecal incontinence:

　　First, treatment

　　The treatment of elderly fecal incontinence should be highly individualized, and different treatment measures should be taken for fecal incontinence caused by different reasons. The elderly usually manifest mild fecal incontinence, and the majority of patients can achieve satisfactory efficacy through conservative medical treatment. The clinical treatment of fecal incontinence includes medical treatment, biofeedback therapy, and surgical treatment.

　　1. Medical Treatment

　　For patients with fecal incontinence, conservative medical treatment should be performed first, which is also the basis for surgical treatment.

　　(1) Adjust diet and lifestyle: Avoid large meals, rough and irritating foods. For patients with solid fecal incontinence, glycerin enema should be administered on schedule after each meal, and patients should be encouraged to be more active.

　　(2) Clean the local area: Keep the perineum clean and dry, and take a sitz bath after defecation. When there is frequent defecation, enema should be performed. For eczema, apply zinc ointment externally.

　　(3) Clearing fecal impaction: Fecal impaction must be cleared in a timely manner. For those who cannot be effectively treated by simple enema, the patient should wear gloves and use their hands to cut the dry, rough fecal mass in the rectum before enema. The purpose of clearing fecal impaction is not only to relieve the impaction but also to prevent recurrence. The most common cause of recurrence is the inability to completely clear the feces in the colon. To prevent recurrence, these patients should regularly perform enema, increase fluid and fibrous dietary intake appropriately, encourage more physical activity, and may add medication for constipation if necessary. In summary, it is necessary to keep the rectum empty and clean.

　　(4) Application of anti-diarrheal agents: For patients after total colectomy or diarrhea, treatment can be given with compound camphor tincture (camphor tincture), benzoate/cinchocaine (compound benzocaine), bismuth subcarbonate (subcarbonate of bismuth), and other medications.

　　(5) Acupuncture: For patients with fecal incontinence caused by peripheral nerve injury, acupuncture treatment can be performed, such as selecting acupoints such as Changqiang, Baihui, Chengshan, etc.

　　2. Biofeedback Therapy

　　In recent years, this method has been used for fecal incontinence with a success rate of 70% to 80%. It has a certain therapeutic effect on patients with idiopathic fecal incontinence who still have some control over the anal external sphincter. The method involves inserting a balloon into the patient's rectum, and the pressure of the balloon allows the patient to see. When the balloon is inflated to a certain volume, the patient should feel the distension of the rectum and exert a perineal contraction action according to the change in balloon pressure. With each inflation of the balloon, the patient performs a perineal contraction action according to the change in balloon pressure that they see. By persistently practicing this feedback training every day, under the premise that the patient can feel the distension of the rectum by the balloon, the inflation volume of the balloon gradually decreases until the patient can establish normal anal-rectal coordination movement. The prerequisite for biofeedback training for patients with idiopathic fecal incontinence is that the patient's anal external sphincter still has some neural control, and the rectum still has a certain sensory ability. For patients who have completely lost neural control, the results of this training are often disappointing. Biofeedback training is a low-cost, rapid-acting, and safe treatment method.

　　3. Surgical Treatment

　　Surgical treatment should be considered for those who are ineffective with conservative medical treatment.

　　(1) Principles of surgical treatment: Surgery should strive to restore the normal anatomical and physiological state of the anal rectum and sphincter muscle. The recovery of sphincter function depends on: ① Restoring the rectum to a sufficiently large and expandable capacity and restoring its compliance; ② Repairing, strengthening, or reconstructing the structure of the internal and external sphincter muscles. During surgery, the anatomical layers should be clear. For sensory incontinence, skin grafting or transposition may be performed. Postoperative functional exercise should be emphasized to facilitate the recovery of defecation function.

　　(2) Selection of surgical treatment methods: The selection of surgical methods includes two aspects: the treatment of the primary disease and the treatment of fecal incontinence. For fecal incontinence secondary to rectal prolapse, injection therapy, rectal mucosal scar support fixation, or transabdominal suspension may be used first. If caused by injury to the external anal sphincter, such as 3 to 4 degrees of obstetric injury and extensive fistula resection, the chance of delayed repair success is higher, and analoplasty and perineal reconstruction are more commonly used procedures with a success rate of about 80%; when combined with sphincter nerve injury, the efficacy is poor. When performing analoplasty for patients with sphincter injury or combined pelvic floor nerve injury, adding anal posterior repair can improve efficacy. There is no satisfactory treatment for neurogenic fecal incontinence; conservative treatment is effective for 40% of patients, and surgical treatment may sometimes be successful. The most commonly used method is anal posterior repair, and 60% to 90% of patients undergoing this surgery can be improved, but only 24% to 58% of patients can control bowel movements 6 to 12 months after surgery. Some data show that combined anterior and posterior pelvic floor repair can improve efficacy, and anal reconstruction can be achieved through muscle strip transplantation. Cure of the primary disease may lead to the disappearance or improvement of anal incontinence.

　　II. Prognosis

　　Conservative medical treatment for fecal incontinence is effective for 40% of patients, surgical treatment improves 60% to 90% of patients, but only 24% to 58% of patients can control bowel movements 6 to 12 months after surgery.