Chapter 36 - Alteration In Digestive Function Flashcards
Four layers of the digestive tract
- Mucosa
- Submucosa
- Muscularis externa
- Serosa
Small intestine (A) epithelial mucosa protection
Single layer
Large intestine (B) epithelial mucosa protection
Inner and outer layers
Structural and neural abnormalities can
Obstruct, slow, accelerate intestinal contents
Inflammatory and ulcerative conditions disrupt
Secretion, motility and absorption
Effects of accessory organs (liver pancreas and gallbladder) can alter
Metabolism
Emesis is Greek for
Vomiting
Vomiting
-forceful emptying stomach/intestinal contents through the mouth
Where is the vomiting center
Medulla oblong at a
Retching
Muscular event of vomiting without vomitus expulsion
Projectile vomiting
Spontaneous vomiting that does not follow nausea or retching
projectile vomiting is caused by
Direct stimulation of vomit center
Invitation of vomiting
Deep inhalation and glottis closes
Abdominal muscles create
Pressure from stomach to throat
Duodenum and stomach antrum
Spasm forcing chyme into esophagus
Upper esophageal sphincter stays closed =
Contents can’t enter mouth
Abdominal muscles relax =
Contents return to stomach
What replaces both esophageal sphincters
Parasympathetic
Abdominal muscles contract =
Force diaphragm high into thoracic cavity causing stomach chyme forced out of mouth
Constipation must be
Individually determined
Wide normal defecation range :
1-3 day to 1 week
Primary constipation
Impaired, infrequent and straining colonic movement
Secondary constipation
Neural pathways are altered, colon transit time delayed
Opiates (codeine)
Inhibit bowel movement
Notable change in constipation can be indicative of
Colorectal cancer
Manifestations of constipation
Straining to evacuate stool may cause hemorrhoids
Diagnosis of constipation
Assess sphincter tone and detect anal lesions
-colonoscopy to help direct lumen view
Treatment for constipation
-restoraLAX
-enemas to establish bowel routine
-collectomy
Colectomy
Remove part of the colon
Acute diarrhea
24 hours or less
Persistent diarrhea
14-28
Chronic diarrhea
Longer than 4 weeks
Osmotic diarrhea
Non absorbable substance in intestine draws excess water to intestine
Secretory diarrhea
Excessive mucosal secretion of fluid and electrolytes
-virus, bacterial toxins, rotavirus
Children and diarrhea, have high rates of
Morbidity and mortality
-younger than 5 years
Motility diarrhea
Excessive motility, causing decreased transit time, and decreased fluid reabsorption
Motility diarrhea is caused by
Surgical bypass of area of intestine
Treatment for diarrhea
-restoration of fluid and electrolyte balance
-anti motility or water absorbent medication
Rotavirus
RNA virus
-causing enteristis
Enteritis
Inflammation of intestinal system
Abdominal pain is caused by
Mechanical, inflammatory or ischemic
-abdominal organs stretching/distension = activation of pain receptors
Parietal pain
From parietal peritoneum
-localized and intense
Visceral pain
Distension, inflammation, ischemic of abdominal organs
-poorly localized with radiating pattern
Upper gastrointestinal intestinal bleeding is found in
Esophagus, stomach and duodenum
Upper gastrointestinal bleeding
Mostly Bright red or dark bleeding
-affected by stomach acids
Upper gastrointestinal bleeding is caused by
Peptic ulcers, tearing of esophageal gastric junction (due to severe retching)
Lower gastrointestinal bleeding is found in
Jejunum, ileum, colon, rectum
Lower gastrointestinal bleeding is caused by
Polyps, inflammatory disease, hemorrhoids
Occult bleeding is caused by
Slow chronic blood loss, not very obvious
Occult bleeding results in
Iron deficiency
-anemia
Presentation of gastrointestinal bleeding
-trace amount of blood in diarrhea or stools
-bp reduction
-compensating tachycardia
-vision loss
Dysphagia
Difficulty swallowing
Mechanical obstruction
Obstruction in esophageal wall
-tumours or herniating
Functional dysphagia
Neural and muscular disorders that interfere with swallowing
Achalasia
Rare form of dysphagia
-smooth muscle neurons of middle/lower esophagus are attacked by immune response
Result of achalasia
Altered esophageal peristalsis
-failure of LES to relax which causes obstruction
What can occur in achalasia
Cough and aspiration can occur
-since there is increased pressure of food being forced past LES
GERD
Gastroesophageal reflux disease
GERD is the reflux of
Acid/pepsin or bile salts into esophagus causing esophagitis
GERD is caused by
Abnormalities in LES function
-resting tone is lower than normal
+delayed gastric emptying of chyme
Severity of esophageal damage depends on
Composition and duration of reflux
Increased acidic chyme exposure =
Mucosal injury and inflammation
(GERD) Persistent =
Fibrosis thickening and precancerous lesions
Diagnosis of GERD
Esophageal endoscopy, tissue biopsy
TX GERD
Laparoscopic fundoplication to tighten junction between esophagus and stomach to prevent acid reflux
Hiatal hernia
Protrusion of superior aspect of stomach through diaphragm hiatal into thorax
Sliding hiatal hernia
So teach moves into thorax through esophageal hiatus
-via opening in diaphragm
Paraesophageal hiatal hernia
Stomach moves into thorax alongside esophageal
Paraesophageal hiatal hernia leads to
Gastritis and ulcer formation
Which type of hernia is GERD associated with
Sliding hiatal hernia
risk of hiatal hernia
Strangulation of hernia causing a medical emergency
Diagnosis of hiatal hernia
Radiology with barium swallow
TX for hiatal hernia
Sleeping with your head up, laparoscopic fundoplication
Intestinal obstruction
Any condition that prevents normal flow of chyme through the intestinal lumen
Paralytic ileus
Causes failure of intestinal motility due to dysfunctional neural activity after surgery
Paralytic ileus is a ____ obstruction
Functional
Large bowel obstruction
Less common
-related to cancer
S/s of large bowel obstruction
Abdominal distension and vomiting
Cause of small bowel obstruction
Postoperative adhesions
-herniation which lead to distension (enlargement)
Small bowel obstruction results in
Distension, causing impaired absorption and increased secretion —> accumulation of fluid, gas, solutes in lumen
Systemic ECF fluid osmotically moves into lumen causing
Decreased ECF —> tachycardia, dehydration and possible shock
Intestinal lumen becomes acidic and leaks..
Pathogens, into systemic circulation —> sepsis
-immune response with possibility of remote organ failure
Adhesions
Organs attacking to each other
Gastritis
Inflammatory disorder of gastric mucosa
acute gastritis
Erosion of protective stomach mucosal barrier by H. Pylori and NSAIDs
NSAIDs inhibit
Prostaglandin synthesis —> which normal stimulates global cell secretion of mucus
H.pylori
Burrows into mucus layers and disrupts function of mucosal layer—> triggers immune response which further destroys mucosal layer
Symptoms/ healing of gastritis
Pain, vomiting
-healing occurs within a few days