Chapter 46: Bowel Elimination

Alterations in elimination are early signs of gastrointestinal problems

purpose of GI organs: absorb fluid and nutrients, prepare food for absorption, temporary storage of feces

Gastrointestinal (GI) tract

series of hollow mucous membrane-lined muscular organs

Digestion begins in the mouth and ends in the small intestine

Mouth- Esophagus- Stomach- Small Intestine

Mouth function

* mechanically, chemically break down nutrients
-Masticate: breaking down into a size suitable for swallowing
-Salivary glands: dilutes and softens food

Esophagus function

* passage of food from mouth to stomach
-esophageal sphincter: circular muscle that prevents air from entering the esophagus and food from refluxing into throat

Bolus

round mass of chewed food

Peristalsis

propels/pushes food through GI via wavelike movement

Stomach function

*Storing swallowed food and liquid; mixing food, liquid and digestive juices; emptying contents into small intestine

Stomach secretes

Hydrochloric Acid (HCL), Mucus, enzyme pepsin, intrinsic factor

Pepsin and HCL facilitate digestion of

Protein

Mucus protects stomach mucosa from acidity and enzyme activity

Intrinsic factor essential for absorption of vitamin B12

Small Intestine

Segmentation and peristaltic movement facilities digestion and absorption

Chyme

pulpy acidic fluid that passes from the stomach to the small intestine, consisting of gastric juices and partly digested food.

Three sections of small intestine

Duodenum, j�junum and ileum

Duodenum

Processes chyme from stomach

Jejunum

Absorbs carbohydrates and proteins

Ileum

Absorbs water, fats and bile salts

Small intestine (Duodenum/Jejunum)

Absorbs most of the nutrients and electrolytes

Small Intestine (Ileum)

Absorbs certain vitamins, iron and bile salts

Nutrients are absorbed into lymph fluids or blood vessels in the intestinal wall

Undigested food from small intestine emptied in Cecum (beginning of large intestine)

Large Intestine- primary organ of bowel elimination

Cecum, colon and rectum

Ileocecal Valve

circular muscular layer that prevents regurgitation (when chyme enters large Int.)

Chyme enters large intestine by wave of peristalsis through ileocecal valve

Colon: ascending, transverse, descending and sigmoid colon

Colon's (large intestine) three functions

absorption
secretion
elimination

Colon absorbs

water sodium and chlorine from digested food

If peristalsis is abnormally fast

less time for water to be absorbed so stool is watery

If peristalsis is abnormally slow

water continues to be absorbed which causes constipation

Secretory function of the colon aids in electrolyte balance

Bicarbonate secreted w/ exchange of chlorine
colon secretes 4 - 9 mEq potassium daily

Intestinal contents stimulates the peristaltic contractions

S

Slow peristalsis pushes content through colon

Fast (mass) peristalsis pushes undigested food toward rectum *4x a day, strongest after mealtime

Bacteria in the rectum convert fecal matter into its final form

Rectum usually empty until the urge is present to go (defecate)

Defecation

discharge of feces from the body

There are fold in the rectum and each fold contains an artery and vein

Hemorrhoid: when artery or vein in rectum becomes distended
*local heat temporarily relieves

Anus

expels feces and flatus; contraction and relaxation aid in controlling defecation

Physiological factors critical to bowel function and defection

-normal GI trat function
-sensory awareness of rectal distention and continence
-voluntary sphincter control
-adequate rectal capacity and compliance

Normal defecation begins

with movement in the left colon (moving stool to rectum)

At the time of defecation

external sphincter relaxes and abdominal muscles contract> increasing intrarectal pressure

Valsalva maneuver

assits in stool passage

Factors affecting Bowel elimination

Age, diet, Fluid intake
Physical activity, Psychological factors
Personal habits, Position during defection
Pain, Pregnancy, Surgery/Anesthesia
Rx, Diagnostic tests

Age (Affects on bowels)

-Babies experience fast peristalsis (incontinence)
-Elderly loose muscle in perineal floor and anal sphincter (incontinence)

Diet (Affects on bowels)

Fiber (non-digestable) provides bulk of real material; promotes peristalsis ex: whole grains, veggies

Lactose Intolerance

Lack the enzyme to break down lactose

Physical activity promotes peristalsis

emotional stress accelerates peristalsis

Colitis

inflammation of lining of colon; irritable bowl syndrome

Crohn's disease

a chronic inflammatory disease of the intestines, esp. the colon and ileum, associated with ulcers and fistulae.

Depression slows down peristalsis

causing Constipation

Pregnancy: As fetus grows it obstructs rectum

Causes slowing of peristalsis > constipation

Paralytic ileus

Paralysis of ileus; usually after surgery or anesthesia; causes constipation

Laxatives, Cathartics

Soften stool and promote peristalsis *Cathartics stinger than laxatives

Endoscopy

an instrument that can be introduced into the body to give a view of its internal parts.

Opioid analgesics (pain Rx)

slows peristalsis > constipation

Antibiotics

disrupts normal bacteria > Produce diarrhea

Aspirin

Interferes with formation of mucus > causes GI bleeding

Iron

Causes discoloration, nausea, vomiting, abdominal cramps > constipation

Constipation

symptoms where there's difficulty emptying bowels

Fecal Impaction

results from unrelieved contraption; collection of hardened feces in rectum that cannot be expelled (several days)

When continuous oozing of diarrhea stool occurs suspect impaction

Excess loss of colonic fluid results in serious fluid and electrolyte (acid-base) imbalance

Diarrhea

increase in number of stools and passage of liquid, unformed feces

Fecal incontinence

inability to control passage of feces and gas from anus (harms clients body image)

Flatulence

accumulation of gas in lumen of intestines; stretching and distention of bowl awl

Thrombosis

purplish discoloration of vein (decreased circulation)

Stoma

temporary or permanent artificial open in in abdominal wall

Bowel Diversion: Ileostomy

Surgical opening created in Ileum (brought through abdominal wall)

Bowel Diversion: Colostomy

Surgical opening created in colon (brought through abdominal wall)

Ostomy (bowel consistency)

Ileostomy: liquid
ascending colon: liquid
transverse colon: slushy
descending colon: pasty
sigmoid: near normal stool

No bowel sounds with paralytic ileus

Gas or flatulence create tympanic note
Masses/tumors/ fluid creates dull note

25% of solid portion of stool is bacteria from the colon

Cannot mix feces with urine/water when getting sample

Fecal Occult Blood Testing (FOBT)

measures microscopic amounts of blood in feces; useful for screening for colon cancer
*blue is positive for blood

One of the most important habits to teach

Take time to defecate (set routine)

Encourage 20g of fiber a day
*Fiber and bulk-forming laxatives first step in treatment for constipation in older adults

Stool softeners no longer recommended for constipation
*Osmotic laxatives

Enema

Promote defecation by stimulating peristalsis

Cleansing enema (complete evac from colon)

tap water, normal saline, soapsuds solution, low volume hypertonic saline

Tap water enema: Hypotonic

Normal Saline enema: isotonic *safest

Hypertonic solution enema: pull fluids out (fleet enema)

Soapsuds enema: castile soap

High/Low enema

Low enema only cleanses sigmoid colon
High enema cleanses entire colon

Digital removal of stool: LAST resort (cannot be delegated)

Move fingers in "scissor" motion when in anus

Purposes of Nasogastric Intubation

Decompression: remove secretions from GI
Enteral feeding
Compression
Lavage

Nasogastric tube (NG)

pliable hollow tube that's inserted through client's nose (nasopharynx) into stomach

12 F NG tube: used for decompression

Salem sump NG tube: has a blue pigtail for air vent

NG tube: burning sensation as tube passes through nare

change tape on nose everyday to reduce irritation
-frequent mouth care (2 hrs)

excoriation

damage of the skin

Turning a client regularly with NG tube promotes emptying of stomach contents

Ostomy and bowel retraining initiated in acute care setting

Effluent

stool discharged from an ostomy

Only a colostomy can be irrigated

Never use an enema, use a cone tipped irrigator

Wound ostomy continence nurse (WOCN)

nurse specially educated to care for ostomy clients

Clean peristomal skin with warm tap water

Do NOT use soap to clean stoma (skin around)

Minimum of 1500 ml of liquid help constipation in older adults

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