FEACAL ELIMINATION.pdf

FEACAL ELIMINATION PHYSIOLOGY OF DEFECATION Elimination of the waste products of digestion from the body is essential to health. The excreted waste products are referred to as feces or stool. Large Intestine The large intestine extends from the ileocecal (ileocolic) valve, which lies betwee...

FEACAL ELIMINATION PHYSIOLOGY OF DEFECATION Elimination of the waste products of digestion from the body is essential to health. The excreted waste products are referred to as feces or stool. Large Intestine The large intestine extends from the ileocecal (ileocolic) valve, which lies between the small and large intestines, to the anus. The colon (large intestine) in the adult is generally about 125 to 150 cm (50 to 60 in.) long. It has seven parts: the cecum; ascending, transverse, and descending colons; sigmoid colon; rectum; and anus. The large intestine is a muscular tube lined with mucous membrane. The muscle fibers are both circular and longitudinal, permitting the intestine to enlarge and contract in both width and length. The longitudinal muscles are shorter than the colon and therefore cause the large intestine to form pouches, or haustra.  The colon’s main functions are the absorption of water and nutrients, the mucoid protection of the intestinal wall, and fecal elimination. The contents of the colon normally represent foods ingested over the previous 4 days, although most of the waste products are excreted within 48 hours of ingestion (the act of taking in food). The waste products leaving the stomach through the small intestine and then passing through the ileocecal valve are called chyme. The ileocecal valve, located at the junction of the ileum of the small intestine and the first part of the large intestine, regulates the flow of chyme into the large intestine and prevents backflow into the ileum. As much as 1,500 mL of chyme passes into the large intestine daily, and all but about 100 mL is reabsorbed in the proximal half of the colon. The 100 mL of fluid is excreted in the feces. The colon also serves a protective function in that it secretes mucus. This mucus contains large amounts of bicarbonate ions. The mucous secretion is stimulated by excitation of parasympathetic nerves. During extreme stimulation—for example, as a result of emotions, large amounts of mucus are secreted, resulting in the passage of stringy mucus with little or no feces.  Mucus serves to protect the wall of the large intestine from trauma by the acids formed in the feces, and it serves as an adherent for holding the fecal material together. Mucus also protects the intestinal wall from bacterial activity. The colon acts to transport along its lumen the products of digestion, which are eventually eliminated through the anal canal. These products are flatus and feces. Flatus is largely air and the by-products of the digestion of carbohydrates. Three types of movements occur in the large intestine: haustral churning, colon peristalsis, and mass peristalsis. Haustral churning involves movement of the chime back and forth within the haustra. In addition to mixing the contents, this action aids in the absorption of water and moves the contents forward to the next haustra. Peristalsis is wavelike movement produced by the circular and longitudinal muscle fibers of the intestinal walls; it propels the intestinal contents forward. Colon peristalsis is very sluggish and is thought to move the chyme very little along the large intestine. Mass peristalsis, the third type of colonic movement, involves a wave of powerful muscular contraction that moves over large areas of the colon. Usually mass peristalsis occurs after eating, stimulated by the presence of food in the stomach and small intestine. In adults, mass peristaltic waves occur only a few times a day Rectum and Anal Canal The rectum in the adult is usually 10 to 15 cm (4 to 6 in.) long; the most distal portion, 2.5 to 5 cm (1 to 2 in.) long, is the anal canal. The rectum has folds that extend vertically. Each of the vertical folds contains a vein and an artery. It is believed that these folds help retain feces within the rectum. When the veins become distended, as can occur with repeated pressure, a condition known as hemorrhoids occurs. The anal canal is bounded by an internal and an external sphincter muscle. The internal sphincter is under involuntary control, and the external sphincter normally is voluntarily controlled. The internal sphincter muscle is innervated by the autonomic nervous system; the external sphincter is innervated by the somatic nervous system. Defecation Defecation is the expulsion of feces from the anus and rectum. It is also called a bowel movement. The frequency of defecation is highly individual, varying from several times per day to two or three times per week. The amount defecated also varies from person to person. When peristaltic waves move the feces into the sigmoid colon and the rectum, the sensory nerves in the rectum are stimulated and the individual becomes aware of the need to defecate. When the internal anal sphincter relaxes, feces move into the anal canal. After the individual is seated on a toilet or bedpan, the external anal sphincter is relaxed voluntarily. Expulsion of the feces is assisted by contraction of the abdominal muscles and the diaphragm, which increases abdominal pressure, and by contraction of the muscles of the pelvic floor, which moves the feces through the anal canal.  Normal defecation is facilitated by (a) thigh flexion, which increases the pressure within the abdomen, and (b) a sitting position, which increases the downward pressure on the rectum. If the defecation reflex is ignored, or if defecation is consciously inhibited by contracting the external sphincter muscle, the urge to defecate normally disappears for a few hours before occurring again. Repeated inhibition of the urge to defecate can result in expansion of the rectum to accommodate accumulated feces and eventual loss of sensitivity to the need to defecate. Constipation can be the ultimate result Feces Normal feces are made of about 75% water and 25% solid materials. They are soft but formed. If the feces are propelled very quickly along the large intestine, there is not time for most of the water in the chyme to be reabsorbed and the feces will be more fluid, containing perhaps 95% water. Normal feces require a normal fluid intake; feces that contain less water may be hard and difficult to expel. Feces are normally brown, chiefly due to the presence of stercobilin and urobilin, which are derived from bilirubin (a red pigment in bile). Another factor that affects fecal color is the action of bacteria such as Escherichia coli or staphylococci, which are normally present in the large intestine. The action of microorganisms on the chyme is also responsible for the odor of feces FACTORS THAT AFFECT DEFECATION Defecation patterns vary at different stages of life, Circumstances of diet, fluid intake and output, activity, psychological factors, defecation habits, medications, diagnostic and medical procedures, pathologic conditions, and pain also affect defecation The new born expels a black, tarry, odorless and sticky first fecal matter called meconium within 24 hours of birth. Their facal matter later becomes greenish yellow, mucoid and loose. Infants pass stool frequently, often after each feeding. Because the intestine is immature, water is not well absorbed and the stool is soft, liquid, and frequent. Infants who are breast-fed have light yellow to golden feces, and infants who are taking formula will have dark yellow or tan stool that is more formed.  Majority of older adults suffer from constipation”. This is due, in part, to reduced activity levels, inadequate fluid and fiber intake, and muscle weakness. Adequate roughage in the diet, adequate exercise, and 6 to 8 glasses of fluid daily are other essential preventive measures for constipation. A cup of hot water or tea at a regular time in the morning is helpful for some. Responding to the gastrocolic reflex (increased peristalsis of the colon after food has entered the stomach) is also an important consideration. Diet Sufficient bulk (cellulose, fiber) in the diet is necessary to provide fecal volume. Inadequate intake of dietary fiber contributes to the risk of developing obesity, type 2 diabetes, coronary artery disease, and colon cancer. Sources of fibre include whole-wheat flour, wheat bran, nuts, and many vegetables, oats, peas, beans, apples, citrus fruits, carrots, barley. Activity Activity stimulates peristalsis, thus facilitating the movement of chyme along the colon. Weak abdominal and pelvic muscles are often ineffective in increasing the intra-abdominal pressure during defecation or in controlling defecation. Weak muscles can result from lack of exercise, immobility, or impaired neurologic functioning. Clients confined to bed are often constipated. Psychological Factors Some people who are anxious or angry experience increased peristaltic activity and subsequent nausea or diarrhea. In contrast, people who are depressed may experience slowed intestinal motility, resulting in constipation. Defecation Habits Early bowel training may establish the habit of defecating at a regular time. Many people defecate after breakfast, when the gastrocolic reflex causes mass peristaltic waves in the large intestine. If a person ignores this urge to defecate, water continues to be reabsorbed, making the feces hard and difficult to expel. When the normal defecation reflexes are inhibited or ignored, these conditioned reflexes tend to be progressively weakened. When habitually ignored, the urge to defecate is ultimately lost. Adults may ignore these reflexes because of the pressures of time or work. Hospitalized clients may suppress the urge because of embarrassment about using a bedpan, because of lack of privacy, or because defecation is too uncomfortable. Medications Some drugs have side effects that can interfere with normal elimination. Some cause diarrhea; others, such as repeated administration of morphine and codeine, cause constipation because they decrease gastrointestinal activity through their action on the central nervous system  Iron supplements act more locally on the bowel mucosa and can cause constipation or diarrhea. Some medications directly affect elimination. Laxatives are medications that stimulate bowel activity and so assist fecal elimination. Other medications soften stool, facilitating defecation. Certain medications suppress peristaltic activity and may be used to treat diarrhea. Medications can also affect the appearance of the feces. Any drug that causes gastrointestinal bleeding (e.g., aspirin products) can cause the stool to be red or black. Iron salts lead to black stool because of the oxidation of the iron; antibiotics may cause a gray-green discoloration; and antacids can cause a whitish discoloration or white specks in the stool. Diagnostic Procedures Before certain diagnostic procedures, such as visualization of the colon (colonoscopy or sigmoidoscopy), the client is restricted from ingesting food or fluid. The client may also be given a cleansing enema prior to the examination. In these instances normal defecation usually will not occur until eating resumes. Anesthesia and Surgery General anesthetics cause the normal colonic movements to cease or slow by blocking parasympathetic stimulation to the muscles of the colon. Clients who have regional or spinal anesthesia are less likely to experience this problem. Surgery that involves direct handling of the intestines can cause temporary cessation of intestinal movement. This condition, called ileus, usually lasts 24 to 48 hours. Listening for bowel sounds that reflect intestinal motility is an important nursing assessment following surgery. Pathologic Conditions Spinal cord injuries and head injuries can decrease the sensory stimulation for defecation. Impaired mobility may limit the client’s ability to respond to the urge to defecate and the client may experience constipation. Or, a client may experience fecal incontinence because of poorly functioning anal sphincters. Pain Clients who experience discomfort when defecating (e.g., following hemorrhoid surgery) often suppress the urge to defecate to avoid the pain. Such clients can experience constipation as a result. Clients taking narcotic analgesics for pain may also experience constipation as a side effect of the medication. FECAL ELIMINATION PROBLEMS Four common problems are related to fecal elimination: constipation, diarrhea, bowel incontinence, and flatulence. Constipation Constipation may be defined as fewer than three bowel movements per week. This infers the passage of dry, hard stool or the passage of no stool. It occurs when the movement of feces through the large intestine is slow, thus allowing time for additional reabsorption Associated with constipation are difficult evacuation of stool and increased effort or straining of the voluntary muscles of defecation. The person may also have a feeling of incomplete stool evacuation after defecation. However, it is important to define constipation in relation to the person’s regular elimination pattern. Some people normally defecate only a few times a week; other people defecate more than once a day.  Careful assessment of the person’s habits is necessary before a diagnosis of constipation is made. Many causes and factors contribute to constipation. Among them are the following: Insufficient fiber intake, Insufficient fluid intake, Insufficient activity or immobility, Irregular defecation habits, Change in daily routine, Lack of privacy, Chronic use of laxatives or enemas, Irritable bowel syndrome (IBS), Pelvic floor dysfunction or muscle damage, Poor motility or slow transit, Neurologic conditions (e.g., Parkinson’s disease), stroke, or paralysis Emotional disturbances such as depression or mental confusion Medications such as opioids, iron supplements, antihistamines, antacids, and antidepressants Habitual denial and ignoring the urge to defecate. FECAL IMPACTION Fecal impaction is a mass or collection of hardened feces in the folds of the rectum. Impaction results from prolonged retention and accumulation of fecal material. In severe impactions the feces accumulate and extend well up into the sigmoid colon and beyond. Impaction can also be assessed by digital examination of the rectum, during which the hardened mass can often be palpated. Along with fecal seepage and constipation, symptoms include frequent but nonproductive desire to defecate and rectal pain. A generalized feeling of illness results; the client becomes anorexic, the abdomen becomes distended, and nausea and vomiting may occur. The causes of fecal impaction are usually poor defecation habits and constipation. Also, the administration of medications such as anticholinergics and antihistamines will increase the client’s risk in the development of a fecal impaction. The barium used in radiologic examinations of the upper and lower gastrointestinal tracts can also be a causative factor. Therefore, after these examinations, laxatives or enemas are usually given to ensure removal of the barium. Diarrhea Diarrhea refers to the passage of liquid feces and an increased frequency of defecation. It is the opposite of constipation and results from rapid movement of fecal contents through the large intestine. Rapid passage of chyme reduces the time available for the large intestine to reabsorb water and electrolytes. Some people pass stool with increased frequency, but diarrhea is not present unless the stool is relatively unformed and excessively liquid. The person with diarrhea finds it difficult or impossible to control the urge to defecate. Bowel sounds are increased. With persistent diarrhea, irritation of the anal region extending to the perineum and buttocks generally results. Fatigue, weakness and emaciation are the results of prolonged diarrhea. Bowel Incontinence Bowel incontinence, also called fecal incontinence, refers to the loss of voluntary ability to control fecal and gaseous discharges through the anal sphincter. The incontinence may occur at specific times, such as after meals, or it may occur irregularly. Two types of bowel incontinence are described: partial and major. Partial incontinence is the inability to control flatus or to prevent minor soiling. Major incontinence is the inability to control feces of normal consistency Fecal incontinence is generally associated with impaired functioning of the anal sphincter or its nerve supply, such as in some neuromuscular diseases, spinal cord trauma, and tumors of the external anal sphincter muscle. Flatulence The three primary sources of flatus are (1) action of bacteria on the chyme in the large intestine, (2) swallowed air, and (3) gas that diffuses between the bloodstream and the intestine. Most gases that are swallowed are expelled through the mouth by eructation (belching). However, large amounts of gas can accumulate in the stomach, resulting in gastric distention. The gases formed in the large intestine are chiefly absorbed through the intestinal capillaries into the circulation Flatulence is the presence of excessive flatus in the intestines and leads to stretching and inflation of the intestines (intestinal distention). Flatulence can occur in the colon from a variety of causes, such as foods (e.g., cabbage, onions), abdominal surgery, or narcotics. If the gas is propelled by increased colon activity before it can be absorbed, it may be expelled through the anus. If excessive gas cannot be expelled through the anus, it may be necessary to insert a rectal tube to remove it. BOWEL DIVERSION OSTOMIES An ostomy is an opening for the gastrointestinal, urinary, or respiratory tract onto the skin. There are many types of intestinal ostomies. A gastrostomy is an opening through the abdominal wall into the stomach. A jejunostomy opens through the abdominal wall into the jejunum, an ileostomy opens into the ileum (small bowel), and a colostomy opens into the colon (large bowel). Gastrostomies and jejunostomies are generally performed to provide an alternate feeding route. The purpose of bowel ostomies is to divert and drain fecal material. Bowel diversion ostomies are often classified according to (a) their status as permanent or temporary, (b) their anatomic location, and (c) the construction of the stoma, the opening created in the abdominal wall by the ostomy. A stoma is generally red in color A person does not feel the stoma because there are no nerve endings in the stoma. Permanence Colostomies can be either temporary or permanent. Temporary colostomies are generally performed for traumatic injuries or inflammatory conditions of the bowel. They allow the distal diseased portion of the bowel to rest and heal. Permanent colostomies are performed to provide a means of elimination when the rectum or anus is nonfunctional as a result of a birth defect or a disease such as cancerof the bowel. The location of the ostomy influences the character and management of the fecal drainage. The farther along the bowel, the more formed the stool (because the large bowel reabsorbs water from the fecal mass) and the more control over the frequency of stomal discharge can be established. For example:  An ileostomy produces liquid fecal drainage. Drainage is constant and cannot be regulated. Ileostomy drainage contains some digestive enzymes, which are damaging to the skin. For this reason, ileostomy clients must wear an appliance continuously and take special precautions to prevent skin breakdown. Compared to colostomies, however, odor is minimal because fewer bacteria are present. An ascending colostomy is similar to an ileostomy in that the drainage is liquid and cannot be regulated, and digestive enzymes are present. Odor, however, is a problem requiring control. A transverse colostomy produces a malodorous, mushy drainage because some of the liquid has been reabsorbed. There is usually no control. A descending colostomy produces increasingly solid fecal drainage. Stools from a sigmoidostomy are of normal or formed consistency, and the frequency of discharge can be regulated. People with a sigmoidostomy may not have to wear an appliance at all times, and odors can usually be controlled. NURSING MANAGEMENT Assessing Assessment of fecal elimination includes taking a nursing history; performing a physical examination of the abdomen, rectum, and anus; and inspecting the feces. The nurse also should review any data obtained from relevant diagnostic tests. Nursing History A nursing history for fecal elimination helps the nurse ascertain the client’s normal pattern. The nurse elicits a description of usual feces and any recent changes and collects information about any past or current problems with elimination, the presence of an ostomy, and factors influencing the elimination pattern. Physical Examination Physical examination of the abdomen in relation to fecal elimination problems includes inspection, auscultation, percussion, and palpation with specific reference to the intestinal tract. Auscultation precedes palpation because palpation can alter peristalsis. Examination of the rectum and anus includes inspection and palpation. Inspecting the Feces Observe the client’s stool for color, consistency, shape, amount, odor, and the presence of abnormal constituents. Diagnosing NANDA International (Herdman & Kamitsuru, 2014) includes the following diagnostic labels for fecal elimination problems: Bowel Incontinence Constipation Risk for Constipation Perceived Constipation Diarrhea Dysfunctional Gastrointestinal Motility. Fecal elimination problems may affect many other areas of human functioning and as a consequence may be the etiology of other  NANDA diagnoses. Examples follow: 1. Risk for Deficient Fluid Volume and/or Risk for Electrolyte Imbalancerelated to a. Prolonged diarrhea b. Abnormal fluid loss through ostomy 2. Risk for Impaired Skin Integrity related to a. Prolonged diarrhea b. Bowel incontinence c. Bowel diversion ostomy 3. Situational Low Self-Esteem related to a. Ostomy b. Fecal incontinence c. Need for assistance with toileting 4. Disturbed Body Image related to a. Ostomy b. Bowel incontinence 5. Deficient Knowledge (Bowel Training, Ostomy Management) related to lack of previous experience Implementing Promoting Regular Defecation The nurse can help clients achieve regular defecation by attending to (a) the provision of privacy, (b) timing, (c) nutrition and fluids,(d) exercise, and (e) positioning. Administering Enemas An enema is a solution introduced into the rectum and large intestine. The action of an enema is to distend the intestine and sometimes to irritate the intestinal mucosa, thereby increasing peristalsis and the excretion of feces and flatus. The enema solution should be at 37.7°C (100°F) because a solution that is too cold or too hot is uncomfortable and causes cramping. Enemas are classified into four groups: cleansing, carminative, retention, and return-flow enemas. Cleansing Enema Cleansing enemas are intended to remove feces. They are given chiefly to: Prevent the escape of feces during surgery. Prepare the intestine for certain diagnostic tests such as x-ray or visualization tests (e.g., colonoscopy). Remove feces in instances of constipation or impaction  Cleansing enemas use a variety of solutions. commonly used solutions are Hypertonic solutions exert osmotic pressure, which draws fluid from the interstitial space into the colon. The increased volume in the colon stimulates peristalsis and hence defecation. A commonly used hypertonic enema is the commercially prepared Fleet phosphate enema. Hypotonic solutions (e.g., tap water) exert a lower osmotic pressure than the surrounding interstitial fluid, causing water to move from the colon into the interstitial space. Before the water moves from the colon, it stimulates peristalsis and defecation. Because the water moves out of the colon, the tap water enema should not be repeated because of the danger of circulatory overload when the water moves from the interstitial space into the circulatory system.  Isotonic solutions, such as physiological (normal) saline, are considered the safest enema solutions to use. They exert the same osmotic pressure as the interstitial fluid surrounding the colon. Therefore, there is no fluid movement into or out of the colon. The instilled volume of saline in the colon stimulates peristalsis. Soapsuds enemas stimulate peristalsis by increasing the volume in the colon and irritating the mucosa. Only pure soap (i.e., Castile soap) should be used in order to minimize mucosa irritation. Carminative Enema A carminative enema is given primarily to expel flatus. The solution instilled into the rectum releases gas, which in turn distends the rectum and the colon, thus stimulating peristalsis. For an adult, 60 to 80 mL of fluid is instilled. Retention Enema A retention enema introduces oil or medication into the rectum and sigmoid colon. The liquid is retained for a relatively long period (e.g.,1 to 3 hours). An oil retention enema acts to soften the feces and to lubricate the rectum and anal canal, thus facilitating passage of the feces. Antibiotic enemas are used to treat infections locally, anthelmintic enemas to kill helminths such as worms and intestinal parasites, and nutritive enemas to administer fluids and nutrients to the rectum. Return-Flow Enema A return-flow enema, also called a Harris flush, is occasionally used to expel flatus. Alternating flow of 100 to 200 mL of fluid into and out of the rectum and sigmoid colon stimulates peristalsis. This process is repeated five or six times until the flatus is expelled and abdominal distention is relieved.