Constipation is a common and complex clinical symptom rather than a disease. It mainly refers to a decrease in the number of bowel movements, a decrease in the volume of stool, dry stool and straining to defecate. It must be combined with the nature of the stool, the usual bowel habits and the difficulty of defecation to make a judgment of constipation. If it is more than 6 months, it is considered chronic constipation.
Etiology
Constipation can be divided into two categories: organic and functional.
1.Organic
(1)Organic lesion of intestinal canal Tumor, inflammation or other causes of intestinal lumen narrowing or obstruction.
(2) Rectal and anal lesions Endorectal prolapse, hemorrhoids, anterior rectal bulge, puborectal hypertrophy, puborectal separation, pelvic floor disease, etc.
(3) Endocrine or metabolic diseases Diabetes mellitus, hypothyroidism, parathyroid disease, etc.
(4) Systemic diseases Scleroderma, lupus erythematosus, etc.
(5) Neurological disorders Central brain disorders, stroke, multiple sclerosis, spinal cord injury, and peripheral neuropathy, etc.
(6) Intestinal smooth muscle or neurogenic lesions.
(7) Colonic neuromuscular pathology Pseudo-intestinal obstruction, congenital megacolon, megarectum, etc.
(8) Neuropsychological disorders.
(9) Pharmacological factors Iron, opioids, antidepressants, anti-Parkinson’s disease drugs, calcium channel antagonists, diuretics, and antihistamines, etc.
2.Functional
The cause of functional constipation is not clear, and its occurrence is related to a variety of factors, including.
(1) eating less or food lack of fiber or water, the stimulation of colonic motility is reduced.
(2) Interference with normal bowel habits due to work stress, fast-paced life, changes in the nature and timing of work, mental factors, etc.
(3) Due to colonic motility disorder, commonly caused by irritable bowel syndrome, caused by spasm of colon and sigmoid colon, with abdominal pain or bloating in addition to constipation, and some patients may show alternating constipation and diarrhea.
(4) Insufficient tone of the abdominal and pelvic muscles, insufficient pushing force for defecation, and difficulty in expelling feces from the body.
(5) Abuse of laxatives, forming drug dependence, resulting in constipation.
(6) Weakness in old age, too little activity, intestinal spasm leading to defecation difficulties, or due to the length of the colon.
3.Classification
Constipation is divided into two main categories according to the pathogenesis: slow transmission type and outlet obstruction type.
(1) Slow transmission type constipation
It is caused by the weakened contractile movement of the intestine, which slows down the movement of feces from the cecum to the rectum, or by the uncoordinated movement of the left hemicocele. It is most common in young women and occurs around puberty, characterized by reduced frequency of defecation (less than 1 defecation per week), less bowel movement, hard stool, and thus difficult defecation; no stool or hard stool is palpated during anorectal examination, while the contraction and forceful defecation function of the external anal sphincter is normal;
Prolonged total gastrointestinal or colonic transit time; lack of evidence of outlet obstruction type, such as normal balloon expulsion test and anorectal manometry. Increased dietary fiber intake with osmotic laxatives is ineffective. Constipation in combination with diabetes, scleroderma and drug-induced constipation are mostly of the slow-transmission type.
(2) Exit obstruction type constipation
It is a disorder of fecal expulsion due to muscle incoordination in the abdomen, anorectum and pelvic floor. It is particularly common in elderly patients, many of whom have failed to respond to conventional medical treatment. The outlet obstruction type may have the following manifestations: straining to defecate, a feeling of incompleteness or falling, a small defecation volume, a desire to defecate or a lack of desire to defecate; a lot of mud-like stool in the rectum on anorectal examination, and the external anal sphincter may contract paradoxically when straining to defecate;
The total gastrointestinal or colonic transit time is normal, and most of the markers may be retained in the rectum; anorectal manometry shows paradoxical contraction of the external anal sphincter during forceful defecation or abnormal sensory threshold of the rectal wall, etc. Many patients with outlet obstruction constipation also have a combination of slow transmission constipation.
Clinical presentation
Constipation has a prevalence of 27% in the population, but only a small percentage of constipated individuals seek medical attention. Constipation can affect people of all ages. It is more common in women than in men, and in older than in younger and older adults. Because of the high prevalence and complex causes of constipation, patients often suffer a lot of distress, and constipation can affect the quality of life when it is severe.
Constipation is often manifested as: less bowel movements, less bowel movements; difficult and laborious bowel movements; poor bowel movements; dry and hard stools, unclean bowel movements; constipation accompanied by abdominal pain or abdominal discomfort. Some patients are also accompanied by insomnia, irritability, dreaminess, depression, anxiety and other psychiatric disorders.
Because constipation is a more common symptom, symptoms vary in severity, most people often do not go to special attention, think constipation is not a disease, no treatment, but in fact, constipation is very harmful. The “alarm” signs of constipation include blood in stool, anemia, weight loss, fever, black stool, abdominal pain, and family history of tumor. If there are alarm signs, you should go to the hospital immediately for further examination.
Examination
In the diagnosis and differential diagnosis of constipation, the necessary tests should be done according to clinical needs. First of all, attention should be paid to the presence of alarm symptoms and evidence of the presence of other organic lesions in the body; colonoscopy should be performed to exclude the possibility of colorectal tumors in patients over 50 years old with a history of long-term constipation and worsening symptoms in a short period of time; for long-term laxative abuse, colonoscopy can determine the presence of laxative colon or (and) colonic melanosis; barium enema angiography can help in the diagnosis of congenital megacolon.
Special tests available for refractory constipation include: gastrointestinal passage test (GITT), rectal and anal manometry (RM), recto-anal reflex test, tolerance sensitivity test, balloon expulsion test (BET), pelvic floor electromyography, pubic nerve latency determination test, and anal canal ultrasonography; colonoscopy or barium enema helps to determine the presence of organic pathology.
Diagnosis
Ask patients about their diet, living habits and work, past history of disease and surgery, especially the history of hemorrhoids, anal fistulas and fissures, recent history of medication, especially the history of long-term laxative use, and clarify the causes of constipation as much as possible through the corresponding examination. For middle-aged patients and above, if there is a change in stool habit from once a day or once every 2 days to once every 3 days or several days, they should be alerted to the possibility of left hemicolectomy.
Treatment
1.General treatment
Patients with constipation need to adopt comprehensive treatment according to the severity, cause and type of constipation, including general life treatment, drug treatment, biofeedback training and surgical treatment, in order to restore normal defecation physiology. Emphasis should be placed on lifestyle treatment, strengthening patient education, adopting reasonable dietary habits, such as increasing dietary fiber content, increasing water intake to enhance stimulation of the colon, and developing good defecation habits, such as morning bowel movements, timely defecation when there is an urge to defecate, avoiding straining to defecate, and at the same time, activities should be increased. Treatment should pay attention to the removal of excessive accumulation of feces in the distal rectum; need to actively adjust the mentality, these are extremely important to obtain effective treatment.
2.Medication
(1)Volumetric laxatives
Mainly including soluble fiber (pectin, plantain, oat bran, etc.) and insoluble fiber (plant fiber, lignin, etc.). Volumetric laxatives have a slow onset of action with few side effects and are safe, so they are more effective for constipation in pregnancy or mild constipation, but are not suitable for rapid laxative treatment of temporary constipation.
(2) lubricating laxatives can lubricate the intestinal wall, softening the stool, so that the stool is easy to discharge, easy to use, such as cork, mineral oil or liquid paraffin.
(3) salt laxatives such as magnesium sulfate, magnesium milk, these drugs can cause serious adverse reactions, clinical caution should be used.
(4) osmotic laxatives
Commonly used drugs are lactulose, sorbitol, polyethylene glycol 4000, etc.. Suitable for blocked feces or as a temporary treatment measure for chronic constipation, is a better choice for constipation patients with poor efficacy of volumetric light laxatives.
(5) Stimulant laxatives
Including anthraquinone-containing plant laxatives (rhubarb, Frangipani, senna, aloe vera), phenolphthalein, castor oil, diethylstilbestrol, etc.. Stimulant laxatives should be used only when volumetric laxatives and salt laxatives are ineffective, some of them are stronger and not suitable for long-term use. Long-term application of anthraquinone laxatives can cause colonic black stool disease or laxative colon, causing atrophy of smooth muscle and damage to the inter-intestinal muscular plexus, but aggravate constipation, reversible after discontinuation of the drug.
(6) prokinetic agents Mosapride, Itopride has a pro-gastrointestinal motility, and Pulucapride can selectively act on the colon, can be selected according to the situation.
3.Device aid
If the stool is hard and stagnant in the rectum near the anal opening or if the patient is old and frail and has poor defecation power or lack of it, the method of colon hydrotherapy or cleansing enema can be used.
4.Biofeedback therapy
It can be used for constipation patients with dysfunction of rectum, anus and pelvic floor muscles, and its long-term efficacy is better. Biofeedback therapy can train patients to relax the pelvic floor muscles during defecation, so that the abdominal muscles and pelvic floor muscle groups can coordinate their activities during defecation; and for patients with abnormal threshold of bowel movement, attention should be paid to the reconstruction of the defecation reflex and the training of adjusting the perception of bowel movement. There are no specific norms for the training program, and the training is more intensive but safe and effective. For patients with pelvic floor dysfunction, biofeedback therapy should be preferred over surgery.
5.Cognitive therapy
Patients with severe constipation often have anxiety or even depression and other psychological factors or disorders, and should be given cognitive therapy to eliminate the patient’s tension, and if necessary, give antidepressant and anti-anxiety treatment, and ask psychologists to assist in the diagnosis and treatment.
6.Surgical treatment
If the constipation is of the type of colonic transmission dysfunction and the condition is serious, surgery can be considered.
Prevention
(1) Avoid eating too little or too fine food, lack of residues, and reduced stimulation of colonic motility.
(2) Avoid disturbance of bowel habits: failure to defecate in a timely manner due to mental factors, change in lifestyle patterns, and overexertion during long trips can easily cause constipation.
(3) Avoid the abuse of laxatives: the abuse of laxatives can make the sensitivity of the intestines weakened, forming a dependence on certain laxatives, resulting in constipation.
(4) Reasonable arrangement of life and work, to achieve a combination of work and rest. Appropriate physical and cultural activities, especially the exercise of the abdominal muscle is conducive to the improvement of gastrointestinal function, more important for sedentary and less active and highly concentrated brain workers.
(5) to develop good bowel habits, regular daily defecation, forming a conditioned reflex, to establish a good bowel pattern. Do not ignore when you have the urge to defecate, and defecate in time. The environment and posture of defecation should be as convenient as possible, so as not to inhibit the desire to defecate and destroy the defecation habit.
(6) Patients are advised to drink at least 6 glasses of 250 ml of water daily, perform moderate exercise and develop the habit of regular bowel movements (2 times a day for 15 minutes). The action potential activity of the colon is enhanced upon waking up and after meals, pushing the stool toward the distal end of the colon, so morning and after meals are the easiest times to defecate.
(7) timely treatment of anal fissures, perianal infections, uterine adnexitis and other diseases, laxatives should be applied with caution, and do not use strong stimulation methods such as bowel cleansing.