Transcript Lecture 9a powerpoint

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
• 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 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.)
• 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.)
• 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.
Altered Bowel Elimination—(cont.)
• 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.
Altered Bowel Elimination—(cont.)
• 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.)
• 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.
Altered Bowel Elimination—(cont.)
• Diarrhea—(cont.)
– Nutrition therapy
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.
Altered Bowel Elimination—(cont.)
• Diarrhea—(cont.)
– Nutrition therapy—(cont.)
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 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.)
• 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
Malabsorption Disorders—(cont.)
• 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
Malabsorption Disorders—(cont.)
• 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
Malabsorption Disorders—(cont.)
• Lactose intolerance—(cont.)
– Lactose is fermented in the colon.
– Produces bloating, cramping, and flatulence
Malabsorption Disorders—(cont.)
• Lactose intolerance—(cont.)
– 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.
Malabsorption Disorders—(cont.)
• Lactose intolerance—(cont.)
– 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.)
• 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)
• Lactose intolerance—(cont.)
– Nutrition therapy
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.
Malabsorption Disorders—(cont.)
• 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.
Malabsorption Disorders—(cont.)
• Inflammatory bowel disease (IBD)—(cont.)
– Characterized by periods of exacerbation
and remission
– Share symptoms and treatment
Malabsorption Disorders—(cont.)
• Inflammatory bowel disease (IBD)—(cont.)
– Nutrition therapy
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.)
• Inflammatory bowel disease (IBD)—(cont.)
– Nutrition therapy—(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.)
• 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.
Malabsorption Disorders—(cont.)
• 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.
Malabsorption Disorders—(cont.)
• Coeliac disease—(cont.)
– 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.
Malabsorption Disorders—(cont.)
• Coeliac disease—(cont.)
– 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.
Malabsorption Disorders—(cont.)
• Coeliac disease—(cont.)
– Nutrition therapy
o Only scientifically proven treatment for
coeliac disease is to completely and
permanently eliminate gluten from the diet
(example of gluten containing foodswheat, rye, barley etc).
o Lactose intolerance secondary to coeliac
disease may be temporary or permanent.
Malabsorption Disorders—(cont.)
• Coeliac disease—(cont.)
– Nutrition therapy—(cont.)
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
Malabsorption Disorders—(cont.)
• 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
Malabsorption Disorders—(cont.)
• Short bowel syndrome (SBS)—(cont.)
– 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.
Malabsorption Disorders—(cont.)
• Short bowel syndrome (SBS)—(cont.)
– 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
Malabsorption Disorders—(cont.)
• Short bowel syndrome (SBS)—(cont.)
– Nutrition therapy
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.
Malabsorption Disorders—(cont.)
• Short bowel syndrome (SBS)—(cont.)
– Nutrition therapy—(cont.)
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 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.)
• Irritable bowel syndrome (IBS)—(cont.)
– Nutrition therapy
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)
Conditions of the Large Intestine—(cont.)
• Irritable bowel syndrome (IBS)—(cont.)
– Nutrition therapy—(cont.)
o Good evidence exists for the use of 5 g of
guar gum daily.
 Guar gum is a soluble, nongelling fibre.
Conditions of the Large Intestine—(cont.)
• Diverticular disease
– Diverticula are caused by increased pressure
within the intestinal lumen.
– Usually asymptomatic
– Diverticulitis occurs when diverticula become
inflamed.
Conditions of the Large Intestine—(cont.)
• 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.)
• 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
Conditions of the Large Intestine—(cont.)
• Diverticular disease—(cont.)
– Nutrition therapy
o Despite a lack of proven efficacy, a highfibre 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.)
• 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.
Conditions of the Large Intestine—(cont.)
• 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 problemsreduced absorption of fluid, potassium and
sodium.
– Ileostomies cause a decrease in fat, bile acid,
and vitamin B12 absorption.
Conditions of the Large Intestine—(cont.)
• 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.
– Nutrition therapy
o Goals of nutrition therapy for ileostomies and
colostomies are to minimize symptoms and
replenish losses.
Conditions of the Large Intestine—(cont.)
• Ileostomies and colostomies—(cont.)
– Nutrition therapy—(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 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
Disorders of the Accessory GI Organs—
(cont.)
• Liver disease—(cont.)
– Acute hepatitis advances to chronic hepatitis,
which may lead to cirrhosis, liver cancer, and
liver failure.
– Glucose intolerance is common.
Disorders of the Accessory GI Organs—
(cont.)
• Liver disease—(cont.)
– Nutrition therapy
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.
Disorders of the Accessory GI Organs—
(cont.)
• Liver disease—(cont.)
– Nutrition therapy—(cont.)
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.
Disorders of the Accessory GI Organs—
(cont.)
• 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.
Disorders of the Accessory GI Organs—
(cont.)
• 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.
Disorders of the Accessory GI Organs—
(cont.)
• 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
Disorders of the Accessory GI Organs—
(cont.)
• 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.
Disorders of the Accessory GI Organs—
(cont.)
• Pancreatitis—(cont.)
– Nutrition therapy
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.)
• Pancreatitis—(cont.)
– Nutrition therapy—(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
Disorders of the Accessory GI Organs—
(cont.)
• Pancreatitis—(cont.)
– Nutrition therapy—(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
Disorders of the Accessory GI Organs—
(cont.)
• 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,