nutrition for patients with disorders of the lower gi tract and accessory organs chapter 18

Nutrition for Patients with Disorders of the Lower GI Tract

and Accessory Organs

Chapter 18


and Accessory Organs

Chapter 18



• Ninety percent to 95% of nutrient absorption occurs in the first half of the small intestine.

• Large intestine absorbs water and electrolytes and promotes the elimination of solid wastes.

• Accessory organs—liver, gallbladder, and pancreas—play vital roles in nutrient digestion.

• Nutrition therapy is used to

– Improve or control symptoms

– Replenish losses

– Promote healing

Altered Bowel EliminationAltered Bowel Elimination

• Constipation

– Difficult or infrequent passage of stools that are hard and dry

– Can occur secondary to irregular bowel habits, psychogenic factors, lack of activity, chronic laxative use, inadequate intake of fluid and fibre, metabolic and endocrine disorders, and bowel abnormalities (e.g., tumors, hernias, strictures)

– Certain medications cause constipation.

Altered Bowel Elimination—(cont.)Altered Bowel Elimination—(cont.)

• Constipation—(cont.)

– Nutrition therapy

o Constipation is treated by treating the underlying cause.

o Increasing fibre and fluid intake effectively relieves and prevents constipation.

o High-fibre diet

Altered Bowel Elimination—(cont.)Altered Bowel Elimination—(cont.)• Constipation—(cont.)

– Nutrition therapy—(cont.)

o Adequate intake set for fibre is 25 g/day for women and 38 g/day for men.

o Common practice is to recommend fibre intake be gradually increased.

o fibre intake should be spread throughout the day.

o Lifestyle changes to promote bowel regularity include drinking more fluid and increasing exercise.


• Diarrhea

– Characterized by more than three bowel movements a day of large amounts of liquid or semiliquid stool

– Potential for dehydration, hyponatremia, hypokalemia, acid–base imbalance (loss of bicarbonate in stool), and hence metabolic acidosis

– Chronic diarrhea can lead to malnutrition related to impaired digestion, absorption, and intake.


• Diarrhea—(cont.)

– Osmotic diarrhea occurs when there is an increase in particles in the intestine, which draws water in to dilute the high concentration.

o Causes include maldigestion of nutrients (e.g., lactose intolerance), excessive intake of sorbitol or fructose, dumping syndrome, tube feedings, and some laxatives.

o Cured by treating the underlying cause

Altered Bowel Elimination—(cont.)Altered Bowel Elimination—(cont.)• Diarrhea—(cont.)

– Secretory diarrhea

o Related to an excessive secretion of fluid and electrolytes into the intestines

o Caused by infections, some medications, some GI disorders, and an excessive amount of bile acids or unabsorbed fatty acids in the colon

o Treatment Antibiotics if cause is infection Symptoms may be treated with medications

that decrease GI motility or thicken the consistency of stools.




o Primary nutritional concern with diarrhea is maintaining or restoring fluid and electrolyte balance.

o Mild diarrhea lasting 24 to 48 hours

Usually requires no nutrition intervention other than encouraging a liberal fluid intake to replace losses

High-potassium foods are encouraged (to replace lost potassium); clear liquids are avoided because they have high osmolality related to their high sugar content, which may promote osmotic diarrhea.




o For more serious cases, commercial (e.g., Pedialyte, Rehydralyte) or homemade oral rehydration solutions, or IV therapy, are used to replace fluid and electrolytes.

o May improve by avoiding foods that stimulate GI motility (e.g. high fibre)

o A low-fibre diet that is also low in fat and lactose may help decrease bowel stimulation.

Malabsorption DisordersMalabsorption Disorders

• Occurs secondary to nutrient maldigestion or from alterations to the absorptive surface of the intestinal mucosa

• Malabsorption related to maldigestion involves one or few nutrients.

• Malabsorption that stems from an altered mucosa is more generalized, resulting in multiple nutrient deficiencies and weight loss.

• Symptoms vary with the underlying disorder.

Malabsorption Disorders—(cont.)Malabsorption Disorders—(cont.)

• Excretion of fat in the stool means that essential fatty acids, fat-soluble vitamins, calcium, and magnesium are also lost through the stool.

• Can cause metabolic complications


• Goal of nutrition therapy for malabsorption syndromes is to:

– Control steatorrhea

– Promote normal bowel elimination

– Restore optimal nutritional status

– Promote healing, when applicable

• Individualized according to symptoms and complications


• Lactose intolerance

– Occurs when the level of lactase is absent or deficient

– Lactose digestion is impaired.

– Undigested lactose increases the osmolality of the intestinal contents.

– May lead to osmotic diarrhea


• Lactose intolerance—(cont.)

– Lactose is fermented in the colon.

– Produces bloating, cramping, and flatulence



– Primary lactose intolerance occurs in “well” people who simply do not secrete adequate lactase.

o Least common in people of northern European descent

o May be asymptomatic when doses less than 4 to 12 g of lactose are consumed (e.g., ⅓ to 1 cup of milk) or when lactose is consumed as part of a meal

o Chocolate milk is usually better tolerated than plain milk.



– Primary lactose intolerance

o Know individual limits

o Lactose-reduced milk and lactase enzyme tablets (taken orally) (e.g. Lactaid) or liquid drops with lactase (e.g. Lacteeze, Lactaid) can be added to liquid foods containing lactose (e.g. milk).

Malabsorption Disorders—(cont.)Malabsorption Disorders—(cont.)• Lactose intolerance—(cont.)

– Lactose intolerance secondary to gastrointestinal disorders that alter the integrity and function of intestinal villi cells, where lactase is secreted

o Loss of lactase may also develop secondary to malnutrition because the rapidly growing intestinal cells that produce lactase are reduced in number and function.

o Tends to be more severe than primary lactose intolerance

Malabsorption Disorders (cont’d)Malabsorption Disorders (cont’d)



o Nutrition therapy for lactose intolerance is to reduce lactose to the maximum amount tolerated by the individual.

o A lactose-free diet is not realistic.


• Inflammatory bowel disease (IBD)

– Primarily refers to two chronic inflammatory GI diseases

o Crohn disease

o Ulcerative colitis

– IBD is believed to be caused by an abnormal immune response to a complex interaction between environmental and genetic factors.


• Inflammatory bowel disease (IBD)—(cont.)

– Characterized by periods of exacerbation and remission

– Share symptoms and treatment


• Inflammatory bowel disease (IBD)—(cont.)


o Depends on the presence and severity of symptoms, the presence of complications, and the nutritional status of the patient

o Diet restrictions are kept to a minimum.

o Patients are often reluctant to eat.

o Crohn disease is more likely to cause nutritional complications.

Malabsorption Disorders—(cont.)Malabsorption Disorders—(cont.)• Inflammatory bowel disease (IBD)—(cont.)


o Focus of therapy for acute exacerbation of IBD is to correct deficiencies by providing nutrients in a form the patient can tolerate.

o For patients consuming an oral diet, low fibre is recommended to minimize bowel stimulation.

o Protein and calorie needs are elevated to facilitate healing.

o Diet modifications are made according to symptoms.

Malabsorption Disorders—(cont.)Malabsorption Disorders—(cont.)• Coeliac disease

– A genetic autoimmune disorder characterized by chronic inflammation of the proximal small intestine mucosa

– Related to a permanent intolerance to certain proteins found in wheat, barley, and rye

– Malabsorption of carbohydrates, protein, fat, vitamins, and minerals may occur, resulting in diarrhea, flatulence, weight loss, and vitamin and mineral deficiencies.


• Coeliac disease—(cont.)

– Symptoms and their severity vary depending on the patient’s age and the duration and extent of the disease.

– Classic symptoms in children are diarrhea, abdominal distention, and failure to thrive.

– Adults present with diarrhea, constipation, weight loss, weakness, flatus, abdominal pain, and vomiting.



– Atypical presentations

– In 15% to 25% of people with coeliac disease, dermatitis herpetiformis is the presenting symptom.

– Symptoms of dermatitis herpetiformis respond to a gluten-free diet.



– People who have a first-degree relative with coeliac disease, people with Down syndrome, and those with an autoimmune disease are at risk for coeliac disease.

– Untreated coeliac disease is associated with an increased incidence of small bowel cancers and enteropathy-associated T-cell lymphoma.




o Only scientifically proven treatment for coeliac disease is to completely and permanently eliminate gluten from the diet (example of gluten containing foods-wheat, rye, barley etc).

o Lactose intolerance secondary to coeliac disease may be temporary or permanent.




o A gluten-free diet requires a major lifestyle change.

o Expensive

• Short bowel syndrome (SBS)

– Occurs when the bowel is surgically shortened to the extent that the remaining bowel is unable to absorb adequate levels of nutrients to meet the individual’s needs


• Short bowel syndrome (SBS)—(cont.)

– Most common reasons for extensive intestinal resections that result in SBS

o Crohn disease

o Traumatic abdominal injuries

o Malignant tumors

o Mesenteric infarction



– Nutrition complications experienced by people with short bowel syndrome depend on the amount and location of resected and remaining bowel.

o Patients who have 150 cm or more of remaining small bowel without a colon, or 60 to 90 cm of small bowel with a colon, initially require PN and may progress to an oral diet over a 1- to 2-year period.



– Factors that influence adaptation

o Length of remaining jejunum and/or ileum and whether the colon is present

o Patient’s age

o Whether the ileocecal value remains

o Health of the remaining bowel

o Health of the stomach, liver, and pancreas




o In the early months after bowel surgery, PN is the major source of nutrition and hydration.

o Consuming intact nutrients promotes bowel adaptation because they stimulate blood flow to the intestine and the secretion of pancreatic enzymes and bile acids.




o Six to eight small meals per day

o If the patient’s colon is intact, fat intake is restricted to avoid steatorrhea and increased fluid losses.

Conditions of the Large IntestineConditions of the Large Intestine

• Irritable bowel syndrome (IBS)

– Many factors involved in its etiology (genetics, stress to name but two)

– Symptoms include lower abdominal pain, constipation, diarrhea, alternating periods of constipation and diarrhea, bloating, and mucus in the stools.

– Can significantly impair quality of life

Conditions of the Large Intestine—(cont.)Conditions of the Large Intestine—(cont.)

• Irritable bowel syndrome (IBS)—(cont.)


o Inconclusive evidence for any of the current treatments used for IBS

o Pharmacologic treatment options

Meet with limited success

o Complementary therapies (peppermint oil and probiotics (in yoghurt, kefir for example) MAY help

o Elimination diet –trying to eliminate potential food intolerances or allergies (elimination of free fructose works for some)


• Irritable bowel syndrome (IBS)—(cont.)


o Good evidence exists for the use of 5 g of guar gum daily.

Guar gum is a soluble, nongelling fibre.


• Diverticular disease

– Diverticula are caused by increased pressure within the intestinal lumen.

– Usually asymptomatic

– Diverticulitis occurs when diverticula become inflamed.


• Diverticular disease—(cont.)

– Symptoms of diverticulitis

o Cramping

o Alternating periods of diarrhea and constipation

o Flatus

o Abdominal distention

o Low-grade fever

Conditions of the Large Intestine—(cont.)Conditions of the Large Intestine—(cont.)• Diverticular disease—(cont.)

– Potential complications

o Occult blood loss and acute rectal bleeding leading to iron deficiency anemia

o Abscesses and bowel perforation leading to peritonitis

o Fistula formation causing bowel obstruction

o Bacterial overgrowth (in small bowel diverticula) that leads to malabsorption of fat and vitamin B12


• Diverticular disease—(cont.)


o Despite a lack of proven efficacy, a high-fibre intake may prevent and improve symptoms of diverticulosis and prevent diverticulitis.

o Once diverticula occur a high fibre diet cannot make them disappear

o Avoid nuts, seeds, and popcorn to avoid them being trapped in diverticula-proposed but no scientific evidence.

Conditions of the Large Intestine—(cont.)Conditions of the Large Intestine—(cont.)•Diverticular disease—(cont.)

– Nutrition therapy—(cont.)o During an acute phase of diverticulitis

Patients are NPO until bleeding and diarrhea subside.

Oral intake resumes with clear liquids and progresses to a low-fibre diet until inflammation and bleeding are no longer a risk.

Thereafter a high-fibre diet is recommended unless symptoms of diverticulitis recur.


• Ileostomies and colostomies

– Performed after part or all the colon, anus, and rectum are removed

– Potential nutritional problems

– The smaller the length of remaining colon, the greater the potential for nutritional problems-reduced absorption of fluid, potassium and sodium.

– Ileostomies cause a decrease in fat, bile acid, and vitamin B12 absorption.


• Ileostomies and colostomies—(cont.)

– Effluent from an ileostomy is liquidy, and fluid and electrolyte losses are considerable.

– Effluent through a colostomy varies from liquid to formed stools.


o Goals of nutrition therapy for ileostomies and colostomies are to minimize symptoms and replenish losses.

Conditions of the Large Intestine—(cont.)Conditions of the Large Intestine—(cont.)• Ileostomies and colostomies—(cont.)


o Initially, only clear liquids that are low in simple sugars to reduce osmotic diarrhea

o Advanced slowly based on individual tolerance

o Fear of eating is common.

o A near-regular diet resumes 6 to 8 weeks after surgery.

o Obtaining adequate fluid and electrolytes is a major concern.

Disorders of the Accessory GI OrgansDisorders of the Accessory GI Organs

• Liver disease

– After absorption, almost all nutrients are transported to the liver.

– Vital for detoxifying drugs, alcohol, ammonia, and other poisonous substances

– Liver damage can have profound and devastating effects on the metabolism of almost all nutrients.

Disorders of the Accessory GI Organs—(cont.)


• Liver disease—(cont.)

– Early symptoms of hepatitis

o Anorexia, nausea and vomiting, fever, fatigue, headache, and weight loss

– Later

o Dark-colored urine, jaundice, liver tenderness, and, possibly, liver enlargement may develop.

– Cell damage reversible with proper rest and nutrition




– Acute hepatitis advances to chronic hepatitis, which may lead to cirrhosis, liver cancer, and liver failure.

– Glucose intolerance is common.





o Objectives of nutrition therapy for liver disease are to avoid or minimize permanent liver damage, promote liver cell regeneration, restore optimal nutritional status, alleviate symptoms, and avoid complications.

o Regeneration may not be possible.

o Patients with acute hepatitis have difficulty consuming an adequate diet.





o Malnutrition is common among patients with cirrhosis. Liver is a major processor of nutrients to ensure WWFQ

o Meeting nutrient and calorie needs is difficult.



• Nutrition therapy for liver transplantation

– Treatment option for patients with severe and irreversible liver failure

– Moderate to severe malnutrition increases the risk of complications and death after transplantation.

– Not one specific posttransplant diet

– Small, frequent meals and commercial supplements may help maximize intake.



• Nutrition therapy for liver transplantation—(cont.)

– Long-term complications associated with immunosuppressive therapy, such as excessive weight gain, hypertension, hyperlipidemia, osteopenic bone disease, and diabetes, may require nutrition therapy.

– Use of immunosuppressant drugs elevates the importance of safe food handling practices to avoid foodborne illness.



• Pancreatitis

– Inflammation of the pancreas

– People with pancreatitis may also develop hyperglycemia related to insufficient insulin secretion.

– Alcohol abuse and gallstones account for more than 70% of cases of acute pancreatitis.

– Acute pancreatitis that is not resolved or recurs frequently can lead to chronic pancreatitis.

o Characterized by scarring, fibrosis, and loss of organ function



• Pancreatitis—(cont.)

– Characterized by intermittent pain that is made worse by eating

– Malabsorption does not occur until pancreatic enzyme secretion is less than 10% of normal.



• Pancreatitis—(cont.)


o Acute pancreatitis is treated by reducing pancreatic stimulation.

o In mild cases, the patient is given pain medications, IV therapy, and nothing by mouth (NPO).

o Small, frequent meals may be better tolerated initially because they help to reduce the amount of pancreatic stimulation at each meal.

Disorders of the Accessory GI Organs(cont.)Disorders of the Accessory GI Organs(cont.)• Pancreatitis—(cont.)


o In moderate to severe acute pancreatitis, patients are ordered NPO and a nasogastric tube is inserted to suction gastric contents.

o Correct any fluid and electrolyte imbalances

o Hypermetabolism and hypercatabolism may increase dietary energy and protein requirements Preferred route of delivering nutrition is enteral feeding if

cannot tolerate oral diet for the upcoming 5-7 days Jejunal feedings preferred-associated with lowest levels of

pancreatic secretions



•Pancreatitis—(cont.)


o Goals of nutrition therapy for chronic pancreatitis are to maintain weight, reduce steatorrhea, minimize pain, avoid acute attacks while meeting the patient’s nutrient needs.

o A mildly low-fat diet that is high in protein is recommended.

o Pancreatic enzyme replacement pills are essential



• Gallbladder disease

– Lower fat diet may be suggested if gall bladder disease is symptomatic but it is not known if patients with gallstones are more intolerant of fat compared to the general population,

nutrition for patients with disorders of the lower gi tract and accessory organs chapter 18

Documents

fibre intake

bowel abnormalities

bowel movements

bowel regularity

inadequate intake of

liberal fluid intake

irregular bowel habits

nutrition therapycont