Chapter 40 Bowel Elimination PDF

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Summary

The gastrointestinal (GI) tract is the body system responsible for the digestion of food and absorption of nutrients and fluids.Normal Structure and Function of the Gastrointestinal Tract Esophagus The esophagus is a collapsible tube, connecting the pharynx to the stomach. From the pharynx, the esop...

Description

! • The gastrointestinal (GI) tract is the body system responsible for the digestion of food and absorption of nutrients and fluids. ! Normal Structure and Function of the Gastrointestinal Tract • Esophagus

sphincter. ! • Stomach

in the left upper quadrant of the abdomen, slightly inferior to the diaphragm.!

‣ Chyme is a thick fluid mass of partially digested food and gastric secretions that is passed from the stomach to the small intestine.!

foods. Pepsin is an enzyme produced in the mucosal lining of the stomach that acts to degrade protein. Intrinsic factor is a protein produced by cells in the stomach lining. It is needed for the intestines to efficiently absorb vitamin B12, which is needed to produce red blood cells. Mucus protects the stomach lining from damage by the gastric acid and enzyme activity • Small intestine

6 meters (18 to 21 feet) in length; it contains three segments.!

protects the intestine by secreting chemicals that neutralize the acidity of the chyme from the stomach before it reaches the jejunum.!

absorption of fats, bile salts, and water. Contents that remain undigested after passing through the small intestine, such as fiber, the indigestible portion of plant foods, empty into the cecum in the lower right quadrant of the abdomen. • Large intestine

colon, transverse colon, descending colon, sigmoid colon, rectum, and anus. Anatomically, the large intestine is located on the periphery of the abdominal compartment and surrounds the small intestine and other structures. Peristalsis, the mechanism of progressive contraction and relaxation of the walls of the intestine, forces chyme into the large intestine through the ileocecal valve, which prevents regurgitation (backflow) of chyme.!

imbalances may occur with alterations in colonic function. Water is absorbed from indigestible food residue. Nutrients and electrolytes, especially sodium and chloride, are absorbed from digested food that has passed from the small intestine. Bicarbonate is secreted in exchange for chloride. The colon excretes 4 to 9 mEq of potassium daily. A mucous layer is in place to help protect the intestinal wall. Waste from the body is eliminated through the formation of feces and expelled from the body by way of the rectum and anus. • Rectum and anus

contents. Each fold contains an artery and a vein that can become distended from pressure during straining. This distention may result in the formation of hemorrhoids. Hemorrhoids are swollen and inflamed veins in the anus or lower rectum.! • Defecation

move the waste into the rectum, the nerves in the rectum are stimulated so that the person becomes aware of the need (urge) to defecate.!

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Altered Structure and Function of the Gastrointestinal Tract • Abnormal defecation patterns

‣ Hyperactive bowel sounds, urgency, abdominal pain, and cramping are characteristics. ! ‣ Ingested materials pass too quickly through the intestine, resulting in a decrease in the amount of time for absorption of fluids and nutrients. ! ‣ Clostridium difficile. is a bacterium that causes diarrhea. ! • It can lead to life-threatening inflammation of the colon. ! • C. difficile infection with associated diarrhea, often called simply “C-diff,” most commonly affects older adults in hospitals and long-term care facilities and typically occurs after use of antibiotic medications. ! • C-diff is easily transmitted by contact, and in recent years these infections have become more difficult to treat.! • The most common clinical symptoms in mild to moderate C-diff consist of occurrence of foul-smelling, watery diarrhea three or more times a day for 2 or more days, accompanied by mild abdominal cramping and tenderness.! ‣ Prolonged diarrhea may lead to nutritional and metabolic disturbances, with resultant fatigue, weakness, malaise, and loss of a substantial amount of fat and muscle tissue, making the patient look extremely thin or emaciated. ! ‣Serious fluid and electrolyte losses can develop within a short time, particularly in infants, small children, and elderly people, causing symptoms of nausea, vomiting, headache, confusion, fatigue, restlessness, and muscle weakness and spasms.

‣ The patient is at risk for skin breakdown and may suffer from social isolation related to embarrassment from the soiling of clothing or use of incontinence products.

movements per week. ! ‣ Slowed intestinal peristalsis and infrequent bowel movements result in increased water absorption in the colon, leading to difficulty passing stool, excessive straining at defecation, the inability to defecate at will, hard feces, and rectal pain.! ‣ In addition, the patient may experience abdominal cramping, pain, pressure, distention, anorexia, and headache.! ‣ Irregular bowel habits, ignoring the urge to defecate, a diet low in fiber or high in animal fats, hemorrhoids, and low fluid intake are causative factors.! ‣ Straining during defecation can induce elevations in intraocular pressure, increased intracranial pressure, changes in cardiac rhythms, and hemorrhoids. ! ‣ The Valsalva maneuver consists of “bearing down” while holding the breath. The person thus is exerting force against a closed windpipe, creating increased intrathoracic pressure. This maneuver causes an extremely rapid rise in blood pressure, which is followed by a fall in arterial blood pressure. Dizziness, blurred vision, and fainting can result.

• Impaction is the result of unresolved constipation. ! • The cardinal sign of impaction is continuous oozing of liquid stool, with no normal stool.! ‣ Barium used in radiologic examinations contributes to the risk for impaction.! ‣ Diagnosis of impaction is by digital examination and palpation of the fecal mass. • Flatulence

the motility of the bowel and may increase flatulence. !

• An ostomy is a surgically created opening in a GI, urinary, or respiratory organ that is exited onto the skin. ! • A stoma (“mouth” in Greek) is any body opening but usually refers to the actual exit point for a GI surgical ostomy, which forms a slight protuberance of mucosa (gut lining tissue) through the skin.! • Bowel diversions or ostomies are created to divert and drain fecal material.

remaining colon is brought through the abdominal wall. ! ‣ A temporary colostomy is used to allow the lower portion of the colon to rest or heal. ! ‣ Permanent colostomies are placed when surgical resection of diseased tissue leads to loss of part of the colon. They are created as a treatment for colorectal cancer or after the lower digestive tract is removed due to illness or disease. Single stomas are created when one end of the bowel is brought out through an opening onto the anterior abdominal

‣ Sigmoid and descending colostomies are the most common type of ostomy surgeries. ! ‣ The end of the descending or sigmoid colon is brought to the surface of the abdomen, usually on the lower left quadrant. The descending colostomy is located higher than the sigmoid colostomy. Both produce solid fecal material.! ‣ A transverse colostomy is created in the transverse colon, resulting in one or two openings. It is located in the upper abdomen, in the middle or on the right side. Transverse colostomies produce semiformed liquid, malodorous drainage because some liquid has been reabsorbed. ! ‣ Ascending colostomies are similar to ileostomies. Drainage is liquid and cannot be regulated. Digestive enzymes are present and cause an odor. Ascending colostomies are relatively rare. The opening is in the ascending portion of the colon and is located on the right side of the abdomen.! ‣ The loop colostomy is a temporary colostomy created in a surgical emergency; it is on the right abdomen. The loop colostomy consists of one stoma with two openings. The proximal end of the stoma is active and discharges stool. The distal end is inactive and may discharge mucus. The loop colostomy is created when a loop of bowel is brought out onto the abdominal wall and supported by a bridge. The loop colostomy procedure results in a large stoma that may be difficult to manage because of its size and inability to be covered with available ostomy products.

at the end of the ileum. The intestine is brought through the abdominal wall to form a stoma. Ileostomies may be temporary or permanent and may involve removal of all or part of the colon. An ileostomy bypasses the large intestine. Stools from an ileostomy are frequent and liquid and cannot be regulated. Drainage contains digestive enzymes, which can be damaging to the skin; therefore patients with ileostomies wear an appliance continuously and take special precautions to prevent skin breakdown. Because few bacteria are present, odor is minimal. Fluid and electrolyte balance is monitored closely for the patient who has an ileostomy in place.! ‣ The ileoanal pouch is now the most common ileostomy. Technically, it is not an ostomy because there is no stoma. In this procedure, the colon and most of the rectum are surgically removed, and an internal pouch is formed out of the terminal portion of the ileum. An opening at the bottom of this pouch is attached to the anus so that the existing anal sphincter can be used for continence. This procedure is performed on patients with ulcerative colitis or familial polyps in whom the anal sphincter is still intact (not removed in previous surgery). Other terms to describe this procedure are a pull-through, endorectal pull-through, pelvic pouch, and J-pouch procedure. After the initial pouch creation, the patient has a temporary ileostomy to allow the anastomosis to heal.! ‣ The Kock pouch is a surgical variation of the ileostomy. A reservoir pouch is created inside the abdomen with a portion of the terminal ileum. A valve is constructed in the pouch, and a stoma is brought through the abdominal wall. A catheter or tube is inserted into the pouch several times a day to drain feces from the reservoir. • Factors affecting bowel elimination

pattern.! ‣ It is recommended that adults include 20 to 35 g of fiber in the diet each day to promote bowel health.! ‣ Poor fluid intake increases the risk for constipation because passage of stool is slower, promoting additional water reabsorption that results in harder stools.

maintains the tone of pelvic and abdominal floor muscles. Weakened abdominal and pelvic floor muscles resulting from lack of exercise, immobility, or altered neurologic function are often ineffective in increasing the intraabdominal pressure during defecation, leading to constipation.

distention often occur. Diseases associated with stress include colitis, Crohn disease, ulcers, and irritable bowel syndrome. Patients with depression may have slowed peristalsis, resulting in constipation.

influence bowel habits in hospitalized patients. ! ‣ Hospitalized patients may have activity intolerance and limited balance because of disease states. The sounds, sights, and odors associated with use of bedpans and bedside commodes, or of shared toilet facilities, are embarrassing to the patient, contributing to development of constipation.

able to effectively contract abdominal muscles making defecation difficult If permitted the head of the patient's bed

is elevated to allow for a position more likely to facilitate defecation. avoid pain. With repeated failure to defecate, constipation may result or become worse. Narcotic pain medications also contribute to development of constipation. Stool softeners may be prescribed.

delivery process can result in hemorrhoid formation. Prenatal vitamins high in iron increase the risk for constipation.

Surgery that requires manipulation of the intestines causes temporary cessation of intestinal movement. The stoppage of peristalsis is called paralytic ileus, which lasts 24 to 48 hours. For patients who remain inactive or are unable to eat after surgery, return of bowel function may be further delayed. Patients whose surgery was conducted with use of spinal or local anesthesia are less likely to experience this problem. Early activity and frequent assessment of bowel sounds are important during this period.

osmotics, salines, stimulants, and stool softeners. Cathartics are strong laxatives that stimulate evacuation of the bowel by causing a change in GI transit time. ! ‣ Antibiotics contribute to diarrhea by interfering with the normal bacterial flora in the GI tract. Anticholinergic drugs inhibit gastric acid secretion and depress GI motility. Opioid analgesics also depress GI motility. Histamine antagonists suppress secretion of hydrochloric acid and interfere with digestion of some foods. Calcium supplements and opioids slow colonic action.! ‣ Drugs that can cause GI bleeding when taken for extended periods, such as nonsteroidal antiinflammatory drugs (NSAIDs), may cause red or black stools, depending on where the bleeding is occurring. Iron salts, which cause constipation, can cause stool to be black. Antacids cause whitish discoloration or white specks.

Prescribed bowel preparations to ensure emptying of the bowel are given to facilitate visualization at endoscopic, radiographic, or other examinations. After the procedure, changes in elimination, such as increased gas and loose stools, may persist until the patient returns to a normal eating pattern.

Assessment • Health history

GI tract. Family history is evaluated for GI cancer, Crohn disease, and other GI disturbances with familial links. • Gastrointestinal tract and abdominal assessment

knees. ! ‣ Determine the contour of the abdomen by viewing at eye level. Abdominal contour may appear flat, round, scaphoid, or protuberant in pregnancy, obesity, or ascites. ! ‣ Abdominal distention may appear as a protuberant abdomen with taut skin. ! ‣ Observe the symmetry of the abdomen, noting bulging, masses, or pulsations. ! ‣ Observe the position of umbilicus; if it is protruding or displaced, a mass or hernia may be present. ! ‣ Observe the abdominal wall for movement. Increased peristaltic activity could indicate an obstructive process. ! ‣ The nurse notes scars, stomas, and lesions during inspection.

the remaining quadrants. ! ‣ Normal bowel sounds are irregular, high-pitched, and gurgling and occur every 5 to 15 seconds. ! ‣ Hyperactive bowel sounds tend to be loud, high- pitched, and rushing; they are commonly heard with diarrhea or inflammatory disorders. ! ‣ Hypoactive bowel sounds are slow and sluggish, with occurrence of less than five sounds per minute. Decreased bowel sounds are common after surgery. ! ‣ Absence of sounds may be a sign of obstruction or paralytic ileus. Patients with ileus or intestinal obstruction require immediate medical attention. The nurse listens for 5 full minutes before documenting the absence of sounds.

‣ The abdomen should be soft, smooth in contour, and pain-free. The patient should be relaxed during palpation, because tense muscles will interfere with palpating underlying organs or masses. In obese patients, bimanual or deep palpation is required to detect underlying organs. If a pulsation is noted on visual examination, do not palpate the area. • Laboratory tests

‣ If the stool culture is positive for pathogenic bacteria, infection is the most likely cause of prolonged diarrhea. !

the stool in association with benign (noncancerous) or malignant (cancerous) growths or polyps in the colon, hemorrhoids, anal fissures, intestinal infections, ulcerative colitis, Crohn disease, diverticular disease, and abnormalities of the blood vessels in the large intestine. GI bleeding may be microscopic (occult blood) or may be easily seen as red blood or black, tar-like stools called melena. The fecal occult blood test requires the collection of three small stool samples taken 1 day apart. The consecutive specimens are collected separately because colon cancers may bleed intermittently. Foods that affect the test results and therefore should be avoided are beets, broccoli, cantaloupe, carrots, cauliflower, cucumbers, fish, grapefruit, horseradish, mushrooms, poultry, radishes, red meat, turnips, and vitamin C–enriched foods and beverages. • Diagnostic examinations

visualize the esophagus, stomach, and duodenum. This series of images assists in the diagnosis of upper GI tract diseases and conditions such as ulcers, tumors, hiatal hernias, scarring, blockages, and abnormalities of the GI tissues. An upper GI study involves some risk from radiation exposure. Patients who are or may become pregnant should notify the radiology department staff, because such studies carry some risk for harm to the fetus from radiation exposure.! ‣ Before the procedure, the patient should not eat or drink anything for 4 to 8 hours. The procedure involves swallowing a liquid that contains barium, which fills and coats the intestinal lining, making the anatomic structures visible. X-ray images are taken at different angles through the chest and abdomen.! ‣ A major side effect of the upper GI series is constipation. Patients who undergo an upper GI study are encouraged to drink extra fluids after the test. A laxative may be recommended to promote evacuation of the bowels if the barium is not eliminated completely within 1 or 2 days. Barium has a whitish appearance that may be apparent in the stool for several days after the test.

of the small intestine to assist in diagnosis of abnormal growths, ulcers, polyps, diverticula, and colon cancer. Barium is inserted into the colon, and then x-ray pictures of the colon and rectum are taken. The barium aids in visualizing the size and shape of the colon and rectum.! ‣ The patient undergoing a lower GI series is informed that the barium will cause fullness and pressure in the abdomen and there will likely be the urge to have a bowel movement. The patient is asked to change positions while x-ray pictures are taken, to obtain different views of the colon.! ‣ To prepare for the procedure, the patient will have a restricted diet for a few days beforehand, generally a liquid diet for the 2 prior days, clear liquids only for 24 hours, and then a laxative or enema just before the procedure. As in the upper GI series, the barium may cause constipation and cause the stool to turn gray or white for a few days after the procedure.

view the inside of the stomach. A duodenoscopy is a procedure to view the inside of the duodenum, the first part of the small intestine. These examinations are performed as a single procedure and are collectively referred to as an upper endoscopy, or esophagogastroduodenoscopy (EGD).! ‣ In this procedure, a fiberoptic endoscope, a flexible instrument with a small camera on the end, is passed through the mouth, down the throat, and into the stomach. Upper endoscopies are prescribed for patients with swallowing difficulties, vomiting, bleeding, gastric reflux, abdominal pain, or chest pain.! ‣ Because direct visualization of the structures is necessary, the stomach must be empty; therefore the patient should not have anything to eat or drink for at least 8 hours before the examination. The patient receives medication that causes drowsiness, relaxation, amnesia, and possibly light-headedness. The throat is sprayed with a numbing medicine that helps prevent discomfort and gagging. The numbness lasts about 30 to 45 minutes. The patient is asked to swallow once or twice during the initial period of insertion to facilitate movement of the endoscope. The tube does not interfere with the patient's ability to breathe and is only mildly uncomfortable after the initial insertion. The examination takes approximately 10 to 20 minutes. During the procedure and afterward, the patient may have a feeling of fullness, because it requires injection of a moderate amount of air to expand the abdomen, allowing for better visualization.! ‣ A biopsy specimen may be obtained for examination, or electrosurgical instruments may be used to treat some medical conditions. Photographs or videos may be taken to document abnormalities. Driving...