The Large Intestine
Ø Primary organ of bowel elimination
Ø Extends from the ileocecal valve to the anus
Functions
Ø Completion of absorption of H2O, Nutrients (chyme from sm. intest. - 1-1.5 L)
Ø Manufacture of some vitamins
Ø Formation of feces
Ø Expulsion of feces from the body
The Small and Large Intestines
Process of Peristalsis
Ø Peristalsis is under control of nervous system
Ø Contractions occur every 3 to 12 minutes
Ø Mass peristalsis sweeps occur 1 to 4 times each 24-hour period
Ø One-third to one-half of food waste is excreted in stool within 24 hours
Peristalic Movements in the Intestine – Colonic peristalsis is slow. Mass peristalsis is strong, few waves per day, stimulated by food in small intestine.
Factors that influence Bowel Elimination
1. Age
2. Diet
3. Position
4. Pregnancy
5. Fluid Intake
6. Activity
7. Psychological
8. Personal Habits
9. Pain
10. Medications
11. Surgery/Anesthesia
Developmental Considerations
Ø Infants—characteristics of stool and frequency depend on formula or breast feedings
Ø Toddler physiologic maturity is first priority for bowel training (1 ½ – 2 yrs)
Ø Child, adolescent, adult—defecation patterns vary in quantity, frequency, and rhythmicity
Ø Older adult—constipation is often a chronic problem
Foods Affecting Bowel Elimination
Ø Constipating foods cheese, lean meat, eggs, & pasta
Ø Foods with laxative effect—fruits and vegetables, bran, chocolate, alcohol, coffee
Ø Gas-producing foods—onions, cabbage, beans, cauliflower
Effect of Medications on Stool
Ø Aspirin, anticoagulants pink, red, or black stool
Ø Iron salts—black stool
Ø Antacids white discoloration or speckling in stool
Ø Antibiotics—green-gray color
Physical Assessment of the Abdomen
