Download Gastrointestinal System

Gastrointestinal System
nutrition
S. Buckley, RN, MS
GI tract anatomy
• 30 ft. long from mouth to anus.
• Consists of mouth, esophagus, stomach,
small intestine, large intestine, rectum, anus.
• Associated organs: liver, pancreas,
gallbladder.
Function of GI tract
• Each part of system performs different
activities.
• Ingestion and propulsion of food: mouth,
pharynx, esophagus.
• Digestion and absorption: mouth, stomach,
small intestine.
• Elimination: large intestine
digestion
Factors affecting GI tract:
• Emotional factors: stress, anxiety..
• Physical factors: diet, alcohol, caffeine,
cigarette smoking, fatigue, organic diseases.
• Emotional and physical factors may be
manifested by anorexia, epigastric and
abdominal pain, diarrhea, constipation.
Stomach
• Function is to store food, mix food with
gastric secretions, and empty contents into
small intestine. Absorbs only small amounts
of water, alcohol, electrolytes and certain
drugs.
• Usual length of time food in stomach: 3-4
hrs.
Stomach
• Chief cells secrete pepsinogen (antecedent
of pepsin-the chief enzyme of gastric juice
which converts proteins into peptones).
• Parietal cells secrete hydrochloric acid,
water and intrinsic factor (increases
absorption of vitamin B complex).
Small intestine
• Functions are digestion and absorption.
• Digestion completed in small intestine,
where carbohydrates and fats are brokendown.
• ~23 ft. long, extends from pylorus to
ileocecal valve. Composed of duodenum,
jejunum, ileum.
Small intestine
• Physical presence of chyme (food mixed
with gastric secretions) stimulates motility
and secretions.
• Secretions include bile from biliary tract,
CCK (cholecystokinin) produced by the
duodenal mucosa, pancreatic enzymes.
Large intestine
• Function is absorption of water and
electrolytes, elimination (forms feces and
serves as reservoir)
• 4 parts: cecum (and appendix), colon
(ascending colon on the right side,
transverse, descending colon on the left
side, sigmoid), rectum, anus.
defecation
• Reflex action involving voluntary and
involuntary control.
Liver
• 4 functions: manufacture (production and
excretion of bile), storage(glucose as
glycogen, vitamins and minerals),
transformation and excretion (phagocyte
system-breakdown of RBC’s, WBC’s and
bacteria) of a number of substances
involved in metabolism.
Biliary tract
• Gallbladder and duct system. Functions to
concentrate and store bile.
Pancreas
• Both exocrine and endocrine functions.
• Exocrine: contributes to the process of
digestion by secreting pancreatic enzymes
(amylase and others).
• Endocrine: secretion of insulin, glucagons,
somatostatin, polypeptide.
Nutrition
• Problems present in all age groups, cultures
and socioeconomic classes in all parts of
world.
• caregivers can act as educator and resource
person can have influence on information
and practices of patients and their families.
Factors affecting nutrition and
diet
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Attitudes
Cultural and/or religious preferences
Economic factors
State of health
Psychological issues
obesity
• 2nd leading cause of preventable death in
U.S.
• 65.2 % of U.S adults are overweight
• Etiology; genetic, environmental
• Methods of measurement; BMIweight/height (p.974) 18-24
• Classifications of body fat distribution
• (gynoid/pear), (android/apple)
obesity
• Influences: culture, economics, habits,
socialization, exercise pattern, work shift
• Diets: calorie in/calorie out.
• Changes: less exercise, larger portions,
more carbohydrates.
• Health consequences: diabetes,
cardiovascular problems, respiratory,
musculoskeletal, Gerd, liver problems.
Essential components of nutrition
• Carbohydrates:chief source of energy,
4kcal/gm.
• Fats: major source of energy,form of
insulation, stored in adipose tissue,
9kcal/gm.
• Proteins:essential for tissue growth and
repair, maintenance, body regulatory
functions, energy production, 4kcal/gm.
Nutrition and diet
• New information constantly influences
percentages of components in diets.
• Daily caloric requirements influenced by
bodybuild, gender, age, physical activity,
level of physical and emotional health.
Nutritional needs
• Infants and children differ from adults: first
months of life, the infant’s GI tract and
kidneys are not functionally mature and are
limited in kinds and quantities of nutrients
needed. Metabolic rate of infants is higher
and they have smaller nutritional reserve
than adults.
Adolescent nutritional needs
• Vulnerable time for development of
nutritional deficiencies due to rapid growth
and bodily changes.
• Extreme concern with body images and
social pressure often affect diet.
• Teenage girls prone to fad diets as means of
weight control, which may not be
nutritionally sound.
Older adults nutritional needs
• Decreases in lean body mass, metabolic rate
and physical activity, thus, decreased
caloric needs.
• Individuals often affected by economic
factors, poor dentition, lack of social
setting, medical conditions, anorexia.
Diet related issues
• Vegetarian diets-can lead to problems associated
with protein and iron deficiencies.
• Vitamins:
• Water-soluble:C and B, excreted via urine. High
levels of C can be associated with formation of
uric acid stones.
• Fat-soluble:A,D, E, K. Can accumulate to toxic
levels.
Constipation
• Decrease in frequency of BM from what is
normal for individual.
• Etiology-insufficient dietary fiber or water,
environment, ignoring urge to defecate,
organic causes, medications.
• Complications-hemorrhoids, diverticulosis,
abdominal discomfort, malaise
Education (regarding constipation)
• Increase fiber-broccoli, apples, carrots,
squash, bran)
• Increase fluids -3 quarts/day
• Exercise-at least 3x week
• Establish regular time to defecate
• Avoid laxatives and enemas
Malnutrition
• May be excess, deficit or imbalance in
essential components of a balanced diet.
• Most common in developing countries with
inadequate food sources, poor economic
conditions or lack of education regarding
nutrition.
Malnutrition-Types
• Protein-calorie-most common cause of
undernutrition, results from primary
(nutritional needs not met as a result of poor
eating habits), or secondary (alteration or
defect in ingestion, digestion, absorption or
metabolism)
Malnutrition terms
• Marasmus-deficiency in caloric and protein
intake leading to generalized loss of body
fat and muscle.
• Kwarshiorkor-deficiency of protein intake
that is superimposed on a catabolic event
(GI obstruction, surgical treatment, cancer,
medications, malabsorption syndromes,
infectious diseases)
malnutrition
• Up to 50% of surgical patients may be
malnourished
• Factors that increase potential for development of
malnutrition: inability to swallow, cognitive
issues, surgery, radiation, chemotherapy, burns,
draining wounds, renal or liver disease,
hemorrhage, bone fractures, malabsorption,
infectious diseases such as TB and AIDS.
Collaborative care
Management of malnutrition
• Hospitalization-determination of etiology
• Treatment of infections secondary to
compromised immune status
• Diet high in calories and protein (oral or
enteral, or parenteral options)
• Correction of fluid and electrolytes
• Social/psychological support
Nutritional disorders
• Malabsorption syndrome-impaired absorption of
nutrients from GI tract. May result from
insufficient enzymes or reduced bowel surface that
leads to deficiencies.
• Symptoms-steatorrhea-bulky, fatty, stools that
float.
• Lactose intolerance-intolerance of milk-based
products.
• Symptoms-flatulence, cramping, “acid stomach”.
Anorexia/bulimia
• Specific psychiatric diagnosis-characterized
by refusal to maintain body weight to
greater than 85% of expected for age and
height.
• Key feature-concern about body image
• Most common in girls and women and
higher economic status.
complications
• Amenorrhea, bradycardia, hypotension, hair
loss, constipation, edema with altered fluid
balance, cardiac complications, malignant
arrhythmias, emotional problems.
Anorexia
• Often common in adolescent girls
• Restrictive eating habits, secretive
• Usually long-standing behavior, familial
tendencies
• Use of laxatives and enemas common
bulimia
• Bulimia-gorging and purging, usually
associated with normal weight. Food
becomes obsession and addiction.
• Self-induced vomiting causes physical
problems of: dental issues, swollen glands,
sore throat, electrolyte imbalances,
dehydration.
Treatment
(anorexia/bulimia)
• Nutritional and psychological support
• Hospitalization may be necessary for
severe physical complications-tube or
parenteral feedings may be utilized, but
only as temporary intervention (not a cure
for anorexia nervosa).
obesity
• Now in epidemic proportions.
• Problems associated when more than 20% over
ideal body weight.
• Associated problems-cardiovascular and
respiratory problems, vascular (hypertension),
diabetes, gallstone formation, sleep apnea,
emotional issues, degenerative joint disease, fatty
liver infiltrates.
Collaborative care
• When no organic cause, should be
considered chronic, complex illness.
• Plan of care should focus on weight loss
with multipronged approach: dietary intake,
physical activity, behavioral-cognitive
modification, medication option.
Surgical intervention
• Gastric bypass technique of choice for
morbidly obese.
• Postoperative care: nutritional,
psychological support, wound monitoring,
respiratory assessment, NG tube
management, pain management.