Overview of Bowel Elimination Flashcards
Structures Involved in Waste Elimination
Small intestine consists of the:
Duodenum
Jejunum
Ileum
Small intestine carries chyme(liquefied food and
digestive juices) from the stomach to the large
intestine.
Chyme arrives at the Ileocecal valve
approximately 4 hours after the meal.
Valve- Controls flow of chyme into the large
intestine
Functions of the Small Intestines
For the small intestine
-Processes chyme into a more liquid state»
Food substances are absorbed into the
bloodstream from the villi on the walls of the small
intestine. Adds bile from the liver to help break
down fats
Villi – finger like on the small intestine walls absorb
nutrients, tiny projections on the inner surface of
the small intestine which help in absorbing the
digested food. These helps to increase the surface
area of intestinal walls.
The small intestine is where most of the long process of digestion
takes place. It:
● Systematically breaks food down.
● Absorbs nutrients.
● Extracts water.
● Moves food along the gastrointestinal tract.
There’s a lot involved in all this. The process can take up to five
hours.
Structures Involved in
Waste Elimination
Large intestine has four main sections:
Large intestine is a large organ located in the digestive system
that is often referred to as the colon
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
Rectum- distal portion of the large intestine feces are stored
Anus. Connects to the anus (opening of the rectum at the skin)
Large Intestine is larger in diameter than the small intestine but
only about 59 inches (1.5 meters long).
Functions of the Large Intestines Cont.
Peristalsis moves chyme and gas through
the intestines (causing bowel sounds)
Normal transit time in intestine is 18 to 72
hours> The slower transport allows reabsorption of minerals,
electrolytes, and water.
Feces is stored in the sigmoid colon until the
gastrocolic reflex initiates defecation
Defecation is under voluntary control and
uses the Valsalva maneuver- A simple technique
that involves breathing out of the nose and mouth while they are
closed. This raises the pressure inside the chest and middle ear
and can equalize pressure in the ears and help reduce some heart
Large Intestine Functions
- Formation and elimination of feces
- Absorption of vitamins
- Absorption of water and electrolytes
- Antibody production
- In large intestine, water, sodium, chlorides
are reabsorbed. - Waste material stored until expelled.
Class Discussion:
Can an individual live without a large intestine?
Reference:
https://www.news-medical.net/health/What-Does-the-Large-Inte
stine-Do.aspx
Slide 12
Structures Involved in Waste Elimination
Walls of the intestine have four layers:
Mucosa-this layer secretes substances that help keep the
innermost parts of the intestine lubricated.
Submucosa- This layer contains blood vessels and
nerves.
Muscular layer- This is a layer of muscle cells that
create peristalsis and segmentation. It is responsible for gut
movement (also called peristalsis).
Serous layer called serosa- Lying on the
outside of the large intestine, the serous layer expels
substances to keep the intestine lubricated against
surrounding organs.
Effects of Aging on the Intestinal Tract
Atrophy of the villi – decrease of the villi in the
small intestine may decrease the total absorptive
surface.
Decreased absorption of fats, vitamin B12 occurs.
Decrease in motility in some individuals but bowel
habits should not change in the normal healthy
individual
Normal Stool and Abnormal Stool
Normal Stool
Another term- is feces
Color: light to dark brown
Consistency: soft-formed in children and
adults; consists of 1⁄4 solids and 3⁄4 water
Infant stool- maybe dark or yellow and
unformed depending on the type of
feedings.
Light dark brown color is caused by bile.
Appearance: affected by diet and
metabolism
Stool is usually tubular in shape and
diameter about 1 inch.
Composition: solid materials consist of
70% undigested roughage from
carbohydrates, fat, protein, and inorganic
matter, and 30% dead bacteria
Abnormal Stool
Most serious is the presence of
blood.
Fresh blood in the stool is easily
visible as bright red on the
surface of the blood.
Occult (hidden)- or old blood is
suspected when the stool
changes from a normal brown
appearance to a dark black color
with a sticky appearance.
Should be promptly recorded in
the patient’s chart and reported.
Abnormal Stool cont.
Blood in the stool: most serious abnormality
Fresh red blood: bleeding in colon, sign of a
recent GI bleeding in the large intestine.
A rule of thumb: the brighter the blood, the lower
the bleeding source.
Occult: upper GI bleed (black stool called melena)
Pale white or light gray stool: absence of bile in the
intestine > obstruction in the bile or common duct
leading to the intestine from the liver to the gall
bladder.
Large amounts of mucus, fat, pus, or parasites such
as worms.
Slide 17
Signs of Upper GI Bleed
What symptoms may indicate upper GI
bleeding?
Some pain and discomfort
the nurse should also look for signs and
symptoms of decreased blood volume; i.e.,
fatigue, shortness of breath, pale conjunctivae,
low blood pressure.
Colorectal Cancer
Initial sign🡪 Changes in bowel patterns and
stool characteristics.
Healthy people 2020 objectives to reduce
colorectal cancers, should encouraged
patients to report these changes and to
participate in colon cancer screening
programs that include annual stool test for
occult blood.
Colonoscopy at the age of 50 then every 10
years if normal or more frequent those with
risk factors (American Cancer Society, 2013).
Hypoactive Bowel and Constipation
Indicates a decrease in peristalsis
▪ Usually results in constipation
Causes
Immobility
Injury to the bowel
Drugs
After abdominal surgery> develop paralytic ileus> peristalsis.
stops due to bowel has been manipulated during surgery.
A patient restricted to bed at risk for constipation.
Drugs That May Contribute to Constipation
Narcotic analgesics
▪ Codeine, morphine, meperidine
▪ General anesthetics- slows peristalsis by depressing
CNS activity.
▪ Diuretics- rid the body fluid
▪ Sedatives- slow CNS activity and peristalsis.
▪ Anticholinergics- alter CNS activity and peristalsis.
▪ Calcium channel blockers- cause a blockade of
calcium channels which affect the smooth muscle of
the intestine
Drugs Used for Constipation
Stool softeners
Colace, Surfak, Dialose
⬤ Bulk-forming laxatives
Fibercon, Metamucil, Citrucel
⬤ Irritant/stimulant laxatives
Dulcolax, Neolid, Ex-Lax, Correctol, Senokot
⬤ Saline laxatives
Citrate of magnesia, milk of magnesia,
phospho-soda
Increase in peristalsis in hyperactive bowel.
Usually results in diarrhea
May be self-limiting
May be self-limiting
Causes
Inflammation of GI tract, infectious diseases,
diseases such as:
Diverticulitis- small, bulging pouches that can form in the lining
of the digestive system. They are found most often in the lower part
of the large intestine (colon).
Ulcerative colitis- causes inflammation outside of
the large intestine.
Crohn’s disease- A chronic inflammation of the digestive tract
that leads to abdominal pain, severe diarrhea, fatigue, weight loss
Hyperactive Bowel and Diarrhea
Drugs
✔ Many antibiotics kill normal bowel bacteria,
resulting in diarrhea
✔ Patients who experience diarrhea from
antibiotics should replace normal flora by:
Eating yogurt
Drinking buttermilk
Taking acidophilus (available OTC)
Acidophilus a bacterium that is used to make
yogurt and to supplement the intestinal flora
Drug-Induced Diarrhea
Laxatives are meant to cause diarrhea
Antacids that have magnesium in them may
also cause diarrhea or make it worse.
Antibiotics also can produce diarrhea.
Chemotherapy medicines used to treat cancer
Metformin cause diarrhea
Medications Used to Control
Diarrhea
Camphorated tincture of opium (paregoric)
Diphenoxylate hydrochloride with atropine
sulfate (Lomotil)
Loperamide hydrochloride (Imodium)
Difenoxin hydrochloride with atropine sulfate
(Motofen)
Class Discussion
What is the bowel sound characteristics for the
patient with diarrhea?
Fecal Incontinence
Lack of voluntary control of fecal evacuation; inability to
retain feces
> Causes
Illness
Cerebrovascular accident
Traumatic injury
Neurogenic dysfunction
> Distressing condition that causes a loss of dignity
Feelings of being less of a person
Loss of self-respect
Embarrassed
Anxiety or fear of losing control
Initial Assessment cont.
Physical assessment
Shape of the abdomen with the patient supine
Flat, distended
Auscultate for bowel sounds in all four quadrants
» Bowel sounds should be auscultated before bowel
palpation and percussion. Auscultating, palpating, or
percussing the heart or lungs has no effect on bowel
sounds.
Percuss for presence of excessive air/gas in the
abdomen
Palpate for masses or tenderness
The most serious abnormality in the stool is:
4) Blood.
Which two groups may become dehydrated
very quickly if diarrhea persists?
3) Infant, elderly
Ostomy, Stoma, and Peristoma Care
Clinical Practice
6) Assist and teach a patient with a bowel
retraining program for incontinence.
7) Evaluate the performance of a patient who is
self-catheterizing a continent diversion.
8) Provide ostomy care, including irrigation and
changing the ostomy appliance.
