Bowel Elimination: Chapter 26 Study Notes

Bowel Elimination: Comprehensive Study Notes

The Gastrointestinal (GI) System

  • Upper GI System Components:
    • Mouth: Where digestion begins with mastication (chewing).
    • Pharynx (throat):
    • Esophagus: The tube connecting the pharynx to the stomach.
    • Stomach:
  • Lower GI System Components:
    • Small Intestine:
    • Large Intestine:
    • Rectum:
    • Anus:

How Bowel Elimination Occurs (The Digestive Process)

  • Mastication: The digestive process initiates with chewing food.
  • Bolus Formation: Food is chewed and mixed with saliva, forming boluses to aid breakdown.
  • Swallowing: The epiglottis closes over the trachea to prevent food from entering the airway during swallowing.
  • Peristalsis: This is the rhythmic contraction and relaxation of smooth muscles that pushes food boluses from the esophagus down toward the stomach.
  • Stomach Function: The stomach stores food and continues its breakdown using hydrochloric acid and protein-digesting enzymes.
  • Small Intestine Function: Food, now in a liquid form, enters the small intestine where nutrient absorption occurs.
  • Large Intestine Function: Undigested food, primarily cellulose and water, moves into the large intestine.
  • Colon's Role: The colon secretes mucus to facilitate stool passage and absorbs essential vitamins and minerals.
  • Rectal Distension: Fecal material collects and reaches the rectum, causing it to distend.
  • Urge to Defecate: The distension of the rectum triggers the relaxation of the internal anal sphincter, creating the urge to defecate.

Bowel Patterns

  • Normal Bowel Pattern:
    • Frequency can vary from several times a day to once per week.
    • Stools are passed without excessive urgency.
    • Minimal effort is required to pass stools, with no straining.
    • Absence of blood loss.
    • No reliance on laxatives.
  • Abnormal Bowel Pattern: Any deviation from the criteria listed above.

Bowel Characteristics: Shape & Consistency

  • Normal Characteristics:
    • Soft, formed, semi-solid texture.
    • Composed of approximately 75%75\% water and 25%25\% solid material when expelled.
  • Abnormal Characteristics:
    • Hard stools.
    • Watery stools.
    • Bloody stools.

Bowel Characteristics: Color and Odor

  • Normal Characteristics:
    • Color: Brown.
    • Odor: Aromatic/pungent.
  • Abnormal Characteristics:
    • Black/tarry stools (may indicate upper GI bleeding or iron supplements).
    • Reddish brown or maroon stools (may indicate lower GI bleeding).
    • Clay-colored stools (may indicate bile duct obstruction).
    • Yellow-green stools (may indicate infection or rapid transit).
    • Foul/objectionable odor.

Factors Affecting Elimination: Adults/Older Adults

Developmental Changes
  • Decreased Peristalsis: Peristaltic activity decreases with age.
  • Reduced Muscle Tone: Perineal muscle tone and sphincter control diminish with aging.
  • Increased Constipation Risk: Older adults have an increased risk for constipation.
Personal and Sociocultural Factors
  • Work Schedule: Fast-paced work environments may lead individuals to ignore the urge to defecate, disrupting normal patterns.
  • Stress: A primary risk factor for irritable bowel syndrome (IBS).
  • Physical Activity: Stimulates peristalsis, promoting regular bowel movements.
  • Sedentary Lifestyle: Decreases peristalsis, increasing the risk of constipation.
  • Positioning: A sitting or semi-squatting position is optimal for effective bowel elimination.
Diet
  • High-Fiber Diet: Increases peristalsis and adds bulk to stool.
    • Examples: Fruit with skin/peel, legumes, whole wheat bread.
  • Low-Fiber Diet: Decreases peristalsis and can lead to constipation.
    • Examples: Pasta, lean meat.
  • Cultured Yogurt: Contains active bacteria that stimulate peristalsis and help restore normal GI flora, which can decrease diarrhea.
  • High-Fat Meats and Greasy Foods: Can increase peristalsis.
  • Spicy Foods: Can irritate the gut and stimulate peristalsis.
Diet: Supplements
  • Calcium: Increases the risk for constipation.
  • Iron: Increases the risk for constipation.
  • Magnesium: Softens stools (e.g., bananas are a source of magnesium).
  • Vitamin C: Can soften stools and may cause diarrhea (e.g., oranges).
Fluids
  • Inadequate Fluid Intake/Excessive Fluid Loss: From conditions like diarrhea or vomiting, can lead to constipation.
  • Excessive Fluid Intake: May potentially cause diarrhea.
  • Coffee: Promotes peristalsis and may lead to loose stools.
Medications
  • Laxatives: Stimulate peristalsis.
  • Antibiotics: Can destroy normal GI flora, leading to diarrhea (e.g., Clostridium difficile overgrowth).
  • Antacids: Generally decrease peristalsis.
  • Pain Medications/Opioids: Significantly decrease peristalsis, a common cause of constipation.
  • Antimotility/Antidiarrheals: Decrease peristalsis to reduce stool frequency.
  • Probiotics: Restore normal GI flora and can help decrease diarrhea.
Surgeries/Procedures
  • Anesthesia: Slows bowel motility after surgery.
  • Bowel Manipulation During Surgery: Can temporarily halt peristalsis.
  • Paralytic Ileus: A cessation of bowel peristalsis, often requiring a nasogastric tube to remove gastric secretions until motility returns.
  • Perineal Surgery: Patients may fear pain or rupture of sutures during defecation, leading to avoidance.
Pregnancy
  • Slowed Gastric Motility: Due to hormonal changes and the uterus crowding and displacing intestines.
  • Iron Supplements: Many pregnant individuals take iron supplements, which contribute to constipation.
Pathological Conditions
  • Neurological Disorders: Conditions affecting the lower GI tract can impair bowel control.
  • Cognitive Conditions: Limit the ability to sense or respond to the urge to defecate.
  • Pain: Can inhibit defecation or be associated with GI issues.
  • Immobility: Reduces physical activity, decreasing peristalsis.
  • Food Allergies/Intolerances: Can cause various GI symptoms, including diarrhea or constipation.
  • Diverticulosis: Formation of small pouches (diverticula) in the colon walls, where fecal matter can become trapped.
  • Diverticulitis: Inflammation or infection of these diverticula.
  • Low-Fiber Diet: Increases the risk for diverticulosis and diverticulitis.

Bowel Diversion

  • Ileostomy:
    • The ileum (part of the small intestine) is surgically brought through the abdominal wall to create a stoma.
    • Completely bypasses the large intestine.
    • Feces are liquid and continuous, as water absorption in the large intestine is entirely bypassed.
  • Colostomy:
    • A portion of the colon is surgically brought to an opening in the abdomen.
    • Feces consistency depends on the location of the colostomy:
      • If closer to the ileocecal valve (beginning of the large intestine), feces will be more liquidy.
      • If closer to the sigmoid colon (end of the large intestine), feces will be more solid.

Altered Bowel Function: Flatulence

  • Flatulence Definition: Accumulation of gas (intestinal flatus) in the GI tract.
  • Sources of Gas:
    • Swallowing Air: Often relieved by belching.
    • Bacterial Action: In the large intestine, relieved through the anus.
      • Gas-producing foods: Broccoli, cabbage, onions, beans.
    • Diffusion from Blood: Less common source.
  • Symptoms: Inability to pass flatus can lead to feelings of fullness, cramping, abdominal distention, and even shortness of breath (SOB).

Altered Bowel Function: Diarrhea

  • Diarrhea Definition: Increased number of stools with the passage of liquid, unformed feces, often accompanied by cramping and bowel urgency.
  • Consequences:
    • Leads to fluid and electrolyte imbalances.
    • Can cause dehydration, evidenced by decreased skin turgor.
    • Antibiotic therapy can lead to an overgrowth of Clostridium difficile (C. Diff), causing severe diarrhea.

Altered Bowel Function: Constipation

  • Constipation Definition: A decrease in the frequency of stools from an individual's normal routine, resulting in hard, dry stools.
  • Symptoms: Can cause abdominal bloating, a distended and hard abdomen, and a full feeling in the rectum.
  • Promoting Relief: Encourage ambulation, a high-fiber diet, and warm fluids.

Altered Bowel Function: Fecal Impaction

  • Fecal Impaction Definition: An accumulation of hardened feces in the rectum, where stool becomes lodged or stuck.
  • Cause: Unrelieved constipation, typically lasting more than 33 days.
  • Signs: May include paradoxical diarrhea or liquid stool oozing/leaking from the rectum, loss of appetite, abdominal distention, cramping, nausea or vomiting, and rectal pain.
  • Risk Factors: Chronic opioid use, insufficient exercise, laxative abuse, and decreased muscle tone.
  • Treatment: May necessitate digital (manual) removal by a healthcare professional.

Altered Bowel Function: Hemorrhoids

  • Hemorrhoids Definition: Enlarged or varicose veins in the anal canal.
  • Cause: Frequently attributed to repeated straining during stool passage.
  • Symptoms: May include swelling, itching, bleeding, burning during/after defecation, and pain when sitting.
  • Anal Fissure: An ulcerous crack or split in the anal mucosa, often caused by hard stools or straining.
  • Consequence: The pain and rectal bleeding associated with hemorrhoids or fissures can cause individuals to ignore the defecation reflex, worsening constipation.

Altered Bowel Function: Fecal Incontinence

  • Fecal Incontinence Definition: Involuntary expulsion of bowel contents.
  • Possible Secondary Conditions: May occur secondary to severe diarrhea or fecal impaction.
  • Impact: Can lead to body image alterations, embarrassment, and skin breakdown due to constant moisture and irritation.
  • Possible Causes:
    • Neurological Impairment: Spinal cord injury, cerebrovascular accident (CVA/stroke), multiple sclerosis (MS).
    • Mental Impairments: Disoriented or confused states that limit awareness of the urge to defecate.
    • Infection: Clostridium difficile (C. diff) overgrowth, leading to severe, uncontrollable diarrhea.

Nursing Process: Assessment - Subjective Data

  • Bowel History: Inquire about normal bowel patterns and characteristics (frequency, consistency, color, odor).
  • Elimination Aids: Ascertain the use of laxatives, suppositories, or enemas.
  • Factors Affecting Elimination: Discuss diet, fluid intake, activity level, stress, and medication use.
  • Chief Complaint: Identify the primary reason for seeking care regarding bowel elimination.
  • Changes in Bowel Routine: Note any recent alterations in bowel habits.
  • Signs/Symptoms of Altered Elimination: Specifically ask about symptoms such as pain, cramping, bloating, urgency, or inability to pass stool/flatus.

Nursing Process: Assessment - Objective Data

Physical Assessment
  • Inspection:
    • Abdomen Contour: Observe for flat, scaphoid (concave), distended (swollen), or symmetrical appearance.
    • Feces Characteristics: Visually assess color, odor, and consistency if visible.
    • Ostomy Assessment (if present):
      • Stoma Appearance: Should be beefy red and moist; pale or cyanotic stoma indicates compromised circulation.
      • Peristomal Skin: Check for irritation, redness, or breakdown around the stoma.
    • Ostomy Supplies: Note the type and fit of ostomy appliances used.
  • Auscultation:
    • Bowel Sounds: Listen for type (absent, hypoactive, active, hyperactive) in all four abdominal quadrants.
    • Documentation Rule: Must listen for at least 55 minutes per quadrant before documenting the absence of bowel sounds.
  • Palpation:
    • Light Palpation: Performed in each abdominal quadrant to detect tenderness, masses, or distention.
    • Peri-rectal Examination: (If symptoms reported, e.g., pain, bleeding)
      • Position patient in side-lying position with knees flexed.
      • Inspect for fissures, hemorrhoids, or bleeding.
    • Digital Rectal Exam (DRE): (Only if necessary and with a healthcare provider's prescription)
      • Insert a lubricated, gloved finger into the anus to feel the rectal walls for stool impaction.
      • Vagal Stimulation Risk: Must assess heart rate before and during the procedure, as vagal nerve stimulation can cause bradycardia (slowing of heart rate).
Intake and Output (I&O)
  • Liquid Stool: Measured in milliliters (mL) using a nun's cap (hat) in the toilet or a graduated cylinder (when emptying an ostomy bag).
  • Solid Stool: Typically measured by occurrence (e.g.,