Digestion and Bowel Elimination

Alterations in Digestion and Bowel Elimination

• Key concepts include GI anatomy and physiology
• Potential changes to GI structures can compromise digestion

Upper GI Tract

• The upper GI tract consists of the mouth, salivary glands, esophagus, and stomach
• Oral structures include the oropharynx, hard palate, gums, teeth, soft palate, tongue, and buccal mucosa
• Esophageal integrity is essential for the movement of partially digested food
• The epiglottis protects the larynx from food entering the trachea
• Esophageal sphincters remain closed at rest
• LES relaxation/ability to transfer food particles is managed by vagus nerve's afferent sensory branch
• Digestion begins in the mouth through mastication and digestive enzymes in saliva
• Salivary and parotid glands aid chewing and swallowing
• Saliva's low pH can break down food

Lower GI Tract

• Consists of the small intestine, large intestine (colon), and rectum
• The small intestine has a "brush border" plasma-rich lining
• The ileum (last 3cm of the small intestine) absorbs remaining nutrients like VB12 and bio acids for reuse
• Chyme (masticated food) goes to the large intestine or colon
• The colon's bacteria flora breaks down fibers and synthesizes vitamins
• The colon absorbs water, electrolytes, and salts and synthesizes/absorbs niacin, VB1, and VK as chyme passes through the ileocecal valve
• The rectum expels water, dead bacteria, and food residue
• Descending colon stores stool
• Nutrients are absorbed when passing through; waste exits via the rectum

Organs

• The liver produces bile
• The pancreas produces digestive enzymes and insulin
• The gallbladder stores bile
• Bile and digestive enzymes help break down food
• Insulin regulates sugar

Nutrient Absorption and Waste Elimination

• Food breaks down through carbohydrate-specific processes amylase/alpha-amylase breaks down starch, glucoamylase transforms simple sugars into glucose

• Disaccharides/double sugars include:

  • Lactase changing milk sugar (lactose) into glucose and galactose
  • Maltase breaking down sugars in malt, cereal grains, and processed foods
  • Sucrase altering table sugar (sucrose) into glucose and fructose

• Vegetable and fiber enzymes include

  • Cellulase and hemicellulose which release nutrients from fruits and vegetables
  • Alpha-galactosidase digests carbs in legumes and cruciferous vegetables
  • Phytase degrades phytates in grains
  • Beta-glucanase breaks down cells in cereal grains and yeast

• Various foods are digested as follows:

  • Mouth digests carbohydrates and fat
  • Stomach digests protein, carbohydrates, and fat
  • Small intestine digests fat, protein, carbohydrates, and nucleic acids

GI Hormones

• Gastrin is located in the stomach
  • Triggered by distention, vagal stimulation, peptides, and amino acids
  • Action: gastric acid and pepsinogen secretion
• Somatostatin is located in delta cells in the antrum of the stomach and pancreatic islets
  • Trigger for acid production in the duodenum
  • Action: impedes hydrochloric acid and gastric secretions while enhancing GI transit
• Gastric inhibitory peptide is located in the duodenal K cells
  • Trigger is amino acids, glucose, duodenal acid, and long-chain fatty acids
  • Action: reduces gastric acid release and enhances GI transit
• Cholecystokinin is located in I cells of the duodenum/proximal jejunum
  • Triggered by amino acids, fatty acids, and proteins
  • Action: gallbladder contraction and sphincter of Oddi relaxation with excretion of pancreatic enzymes
• Secretin is located in the S cells of the duodenum and proximal jejunum
  • Trigger is duodenal fat, acid, or bile
  • Action: H2O and bicarb released from the pancreas, bile alkalization
• Vasoactive intestinal peptide is located in the GI tract, in neuroendocrine cells
  • Trigger is vagal stimulation, acetylcholine release, and fat presence
  • Action: enhances water and electrolyte secretion, speeds motility, and prevents gastrin release
• Motilin is located in the duodenum & jejunum
  • Trigger is stimulation of acid, vagal stimulus, and gastrin-releasing peptide
  • Action intensifies motility
• Ghrelin is located in the stomach
  • Trigger is fasting
  • Action stimulates growth hormone release and appetite
• Gastrin-releasing peptide (bombesin) is located in the stomach/small intestine
  • Trigger is following a meal
  • Action provokes GI hormone release to stimulate fullness

Pain and Discomfort from GI Disorders

• Ostomies are performed if a patient has a significant GI disorder, GI obstruction, postsurgical bowel rest, or short bowel syndrome
• Electrolyte imbalances, vitamin/mineral deficiencies, malabsorption, malnutrition, and loose blood in the stool (anemia) can occur

Gallbladder

• Cholecystitis is associated with the "6 F's": female, fat, fair, fertile, forty, flatulence
• S/S include indigestion, fever, increased WBC, intolerance to fatty/spicy foods, N/V, clay-colored stool, and RUQ pain
• Diagnosis is by ultrasound to look for sludge from inflammation
• Interventions: support therapy, maintain electrolyte balance, antibiotics, prevent flare-ups, low-fat diet, NG if vomiting, minimize stimulation, analgesics, cholecystectomy, lithotripsy (sometimes with a T-tube insertion for drainage)

Pancreas

• Pancreatitis causes severe epigastric pain and radiates to the back

Liver

• Associated conditions include carcinoma, liver failure, cirrhosis, ALD, NAFLD, and hepatitis
• Risks are family history, autoimmune issues, smoking, increased age, injury to the abdomen, and EtOH use
• Comorbidities include obesity, DM, CF, hyperlipidemia, high calcium, and pancreatic cancer
• Alcoholic liver disease is linked to metabolic disorders and is the principle cause of liver disease with approximately half the adults meeting criteria
• Non-alcoholic fatty liver disease is prominent in western cultures and often requires a liver transplant, with comorbidities such as central obesity, dyslipidemia, DM2, and hyperglycemia
• Hepatitis symptoms include palmar erythema, jaundice, distended abdomen (ascites), and spider veins/angioma, impacting daily life
• Hepatitis is transmitted via
  • fecal and oral routes in A/E types
  • contact with infected blood in C type
  • contact with infected blood and body fluids in B/D types
• A/B types have a vaccine
• Nurses should promote no EtOH, low-fat diets, monitor liver enzymes, promote healthy activities, and limit exposure to friends/family, VS and palpate lymphs and abdomen (light/deep)
• Other risks includes genetics, obesity, and concurrent infections, or smoking
• Untreated, it can advance to liver failure> hepatocellular carcinoma

Stomach and Duodenal Conditions

• Gastritis is acute inflammation of the esophageal mucosa and erosion of the stomach caused by stress, NSAIDs, EtOH, or Uremia, with burns as a risk factor
• Chronic gastritis is long-term irreversible inflammation of the mucosal lining caused by autoimmune issues or H. Pylori infection, impacting the antrum and is a risk for progressive metaplasia and atrophy
• Hiatal hernia causes heartburn and sour taste after food intake, diagnosed by ultrasound, EGD scope, pH monitoring, or esophagography

Stomach Ulcers

• S/S include severe abdominal pain (burning/gnawing), especially after meals or at night, poor nutrition due to difficulty eating/loss of appetite, n/v, bloating and occult stool/bloody vomit with feeling full quickly after eating
• Diagnostic criteria include identifying open sores in the stomach lining potentially caused by H. pylori as well as long term NSAID, EtOH use, or family history as well as being older than 60
• Common comorbid conditions include type O blood or Crohn's disease
• Testing includes upper GI scope, stool antigen, occult fecal test, urea breath test, and labs
• Treatment: food restrictions (like GERD), no EtOH/smoking, limit stress, PPI administration and nurse teachings (S/E of diarrhea, constipation, abd pain, and flatulence as well as potential hypocalcemia, hypomagnesemia, osteoporosis, and VB12 deficiency)

Disorder in GI Tract

• Mouth sores, herpes simplex, or canker sores (apthosis) can cause stinging-pain and limit oral intake (especially in children); common on long-term basis
• Oral cancer can be painful with a burning sensation, with cancer and chemo causing lesions and thrush can cause oral lesions
• Barrett's esophagus alters structure and function, related to chronic GERD inflammation and linked to esophageal adenocarcinoma, with erosion from highly acidic fluid causing severe damage to the mucosa in LES

Oral Cavity

• 1/3 globally affected by herpes
• Oral candidiasis has 2mil cases annually
• Periodontitis leads to tooth loss and alveolar bone destruction
• Oral cancer accounts for 48% of all head and neck cancers
• Periodontal tooth loss affects 75% of the US population
• Untreated gum disease can increase the risk of CAD
• Oral swallowing challenges can change tissue composition
• Better mouth/teeth health → better overall health/nutrition
• Nurses must be aware of the oral health challenges of older-aged people or those living in poverty
• Social determinants affect nutrition and cardiovascular health and promote healthy gum and tooth care
• Tooth sensitivity/pain cause difficulty eating & chewing, with gingivitis and plaque build-up
• Excellent dental care is needed to prevent tooth loss
• Early intervention can reverse inflammation and destructiveness

Environmental Factors, Patient Safety

• Genetic/environmental factors include heredity, alcohol intake, smoking, and long-term stress
• Nurses should educate on hygiene, washing hands, oral care, proper toothbrush care, care of dentures/braces, nutrition, tobacco use, and regular dental care with professionalism
• Impact is on overall health

Common Conditions

• Gastroesophageal Reflux Disease (GERD) is very common

• Where acid travels up the esophagus and erodes the lining

  • Patho- relaxed lower esophageal sphincter

• Stress exacerbates it; severity may be affected by stress level

• Chronic episodes lead to barrett's esophagus and strictures with serious diseases and quality of life issues like hiatal hernia, connective tissue disorders, pregnancy, burping, passing gas, stress

• Signs and symptoms include:

  • Dyspepsia
  • Indigestion
  • Heartburn (pyrosis)

• Interventions: Education (no smoking/EtOH/fatty foods/caffeine), smaller and more frequent meals with high fowlers for meals and 30 mins afterward

• Peptic Ulcer Disease (PUD) Signs and Symptoms include: Abd pain, Melena, Pyrosis (heartburn), GI stress, and weight changes and occurs mostly in the duodenum and is relieved by eating

  • Caused by NSAIDS and H Pylori

• Is associated with increased stomach acid

• Inflammatory Bowel Disease includes Crohn's, affecting any part of the GI tract, Functional disorder (no organic cause found) and the Ulcerative Clotis, affectinf only the colon Signs and Symptoms include diarrhea, rectal bleeding, abscess formation, fistulas around the anus, skin lesions, as well as joint pain and a S/S include stool urgency, increased BM, abd pain, mucous in the stool, night stools, LLQ, and bright red rectal bleeding

• Diverticulitis S/S includes Abd pain (LLQ) N/V/D/C, and TTP with complications such as Abscess formation, bowel blockage, fistula development, peritonitis

• Celiac: Cillia slough off w the intestinal lining S/S include Bloating, anemia, wt loss, fatigue, inability to absorb nutrients, rash, diarrhea, as well as steatorrhea with Testing that includes Bowel biopsy and/or Antibody testing.

• Irritable Bowel Syndrome (IBS)

  • A functional gastrointestinal disorder characterized by chronic abd pain abd altered bowel habits

Types include

• IBS-C (constipation dominant)
• IBS-D (Diarrhea dominant)
• IBS-M (mixed)
• IBS-U (unclassified)
  • S/S include Abd pain, bloating, gas, diarrhea, constipation, and mucous in stool that include Trigger of Stress, certain foods (caffeine, fatty foods, lactose, gluten), hormonal changes, and GI infections Red flags are Weight loss, blood in stool, anemia, and/or fever
• Bowel Obstruction: Blocker that prevents the normal flow of intestinal contents through the digestive tract that can occur in either large or small intestine and can be either partial or complete
• Types-
• Mechanical: a physical blockage from Adhesions, tumors, hernias, volvulus, intussusception, and/or fecal impaction
• Non-mechanical (functional ): a paralyzed ileus when bowel doesn't move properly, often after surgery, due to medications or electrolyte imbalances
• S/S- Abd pain/cramping, distention, N/V , absence of flatus or stool, bowel sound changes , constipation or ribbon-like stools, dehydration and electrolyte imbalances
• Interventions NPO status, IV fluids for hydration and electrolytes, NG tube, Semi fowlers to relieve pressure Pain control
• Interventions Monitor I/O and hydration status - MOST IMPORTANT, Admin meds, and contacting precautions for infections
• Colorectal Cancer: Cancer that starts in the colon or rectum. Often begins as noncancerous polyp that turns cancerous over time
• Risk factors:
• Age over 50, family hx, personal hx of polyps or IBD, diet high in red/processed and low in fiber, smoking, EtOH, sedentary lifestyle, genetic conditions such as lynch syndrome
• Symptoms
• Rectal bleeding and/or blood in the stool, persistent abdominal discomfort, gas, cramps, pain, unexplained weight loss, change in bowel habits, diarrhea, constipation, narrowing of stool, fatigue, and anemia-related Symptoms
• Constipation and Diarrhea
• Diarrhea: Increased frequency of lose, watery stools . Common caused included viral, bacterial, and/or parasitic Infections that might include Medication of abx, chemo, and/or magnesium
• Interventions: Monitor I/O and hydration status - MOST IMPORTANT, Replace fluids/electrolytes - MOST IMPORTANT, Admin meds, Contact precautions for infections,and Hand hygiene

Alterations in Neurologic Function

• Key Concepts:
• Central and peripheral nervous system function

Central-

• Brain and spinal cord
• Brain: controls thought, memory, emotion, touch, motor skills, vision, breathing, temperature, and more
• Spinal cords transmits signals between the brain and the rest of the body Neuro assessment
• LOC - GCS
• Pupil size and reactivity
• Motor function (strength, symmetry, coordination)
• Sensory function
• Speech/language abilities Common conditions-
• Stroke (CVA/TIA)
• TBI
• Seizures
• Meningitis
• Multiple sclerosis
• Parkinson’s Red flags
• Sudden changes in LOC
• Unequal pupils
• New onset of confusion or slurred speech
• Seizure activity Peripheral
• Spinal nerves, cranial nerves
• Connects CNS to limbs and organs
• Somatic
• Voluntary control (i.e. moving limbs)
• Autonomic
• Involuntary control (i.e. HR, digestion)
• Divided into two