chapter 45: disorders of gastrointestinal function

Question 1

signs and symptoms common to gastrointenstinal disorders

Answer 1

• anorexia
• nausea
• vomiting
• gastrointestinal bleeding

Question 2

Anorexia, nausea, retching, and vomitting

Answer 2

• anorexia, nausea, and vomiting are physiologic responses that are common to many GI disorders
• Retching consts of the rhythmic spasmodic movements of the diaphragm, chest wall, and abdominal muscles
• signal for disease and removes noxious agents
• contributes to impaired intake or loss of fluids and nutrients

Question 3

vomiting and neural structures

Answer 3

• vomiting involves two functionally distinct medullary centers- the vomiting center and the chemoreceptor trigger zone
• vomiting center: located in the medulla near the sensor nuclei of the vagus nerve
• Chemoreceptor trigger zone: located in small area on the floor od the brains fourth ventricle, where it is exposed to both blood and cerebospinal fluid. reacts to the emetic effects of blood-borne drugs and toxins

Question 4

swallowing

Answer 4

• mechanisms:
  
  • depends on the coordinated action of the tongue and pharynx
  • theses structures are innervated by cranial nerves V,IX, X
• alterations:
  
  • dysphagia: difficulty swallowing
  • Odynophagia: painful swallowing
  • achalasia: failure of the esophageal sphincter to relax

Question 5

Gastroesophageal Reflux a.k.a GERD

Answer 5

• heart burn: 30-60 minutes adter meal, typically an evening onset, pain in the epigastric area (can radiate),
• how to overcome GERD?
  • avoid large meals, smoking, alcohol, bending for long periods or with pillows, recumbent position several hours after a meal
  • eat meals sitting up, sleep with head of bed elevated, losing weigh if overweight

Question 6

Complaints accompanying esophageal

Answer 6

the food stops before it reaches the stomach,

gurgling, belching, coughing, foul-smelling breath

Question 7

esophageal cancer

Answer 7

-squamous cell carcinoma
+alcohol and tobacco use
-Adenocarcinoma
+which has a close association with Barret’s esophagus (reflux leads to metaplasia of epithelial cells which can lead to cancer in lower esophagus)
-Symptoms
+dysphagia, weight loss, anorexia,fatigue,painful swallowing, not easily diagnosed

Question 8

factors contributing to the protection of gastric mucosa

Answer 8

• gastric mucosal barrier exists in the stomach
  + there should be an impermeable epithelial cell surface covering protecting the stomach
  +there are mechanisms for the selective transport of hydrogen (hydrocholric cid) and bicarbonates ions
  + there are 2 characteristic types of gastric mucus

Question 9

Types of mucus protecting the gastric mucosa

Answer 9

-water-insoluble mucus: +forms, a thin stable gel that adheres to the gastric mucosal surface. +Provides protection.
+forms an unstirred layer that traps bicarbonate, forming an alkaline interface between the luminal contents of the stomach and its mucosal surface

-water-soluble mucus
+washed from the mucosal surface
+mixes with the luminal contents
+ its viscid nature makes it a lubricant that prevents mechanical damage to the mucosal surface

Question 10

major cause of gastric irritation and ulcer formation

Answer 10

• Asipirin or nonsteroidal anti-inflammatory drugs (NSAIDS): irritates the gastric mucosa and inhibit prostaglandin synthesis
• infection with H.pylori: thrives in an acid environment of the stomach & disrupts the mucosal barrier that prtects the stomach from harmful effects of its digestive enzymes

Question 11

Types of gastritis

Answer 11

• acute gastritis

- chronic gastritis

Question 12

acute gastritis

Answer 12

• a transient inflammatino of the gastric mucosa

- most commonly associated with local irritants such as bacterial endotoxins, alcohol, and aspirin

Question 13

chronic gastritis

Answer 13

• characterized by the absence of grossly visible erosions and the presence of chronic inflammatory changes
• leads eventually to atrophy of the glandular epithelium of the stomach

Question 14

major types of chronic gastritis

Answer 14

• helicobacter pylori gastritis
• autoimmune gastritis
• multifocal atropic gastritis
• chemical gastropathy

Question 15

Helicobacter pylori

Answer 15

• colonize the mucus-secreting epithelial cells of the stomach
• produce enzymes and toxins that have the capacity to interfere with the local protection of the gastric mucosa
• produce intense inflammation
• elicit an immune response

Question 16

methods establishing presence of H. Pylori infection

Answer 16

• C urea breath test using a radioactive carbon isotope
• stool antigen test
• endoscopic biopsy for urease testing
• blood tests to obtain serologic titers of H. Pylori antibodies

Question 17

peptic ulcers

Answer 17

ulcerative disorders that occur in areas of the upper GI tract that are exposed to acid-pepsin secretions
-spontaneous remissions and exacerbations are common
-causes
+H. pylori, aspirin, age, warfarin, smoking

Question 18

complications of peptic ulcer

H.O.P

Answer 18

-Hemorrhage
+cause by bleeding from granulation tissue or from erosion of an ulcer into an artery or vein

-Obstruction:
+ caused by edema,spasm, or contraction of scar tissue and interference with the free passage of gastric contents through the pylorous or adjacent areas

-Perforation
+occurs when an ulcer erodes through all the layers of the stomach or duodenum wall. bleeding and spilling of gastric contents into the perotoneum could be fatal

Question 19

GI tract bleedin

Answer 19

-HEMATEMESIS
+ blood in the vomitus
+ may be bright red or have coffee groun appearance

-MELENA
+blood in the stool
+ranges in color from bright red to tarry black
+may be occult (hidden). we can hemoccult test

Question 20

Treatment of Peptic Ulcer

Answer 20

-Eradicate the cause and promote a permanent cure for the disease, usual meds:
-Eradicating H. pylori with 2 antibiotics
+Mucosal protective like Carafate
+Antacids to relieving ulcer symptoms like Maalox, Tums
+Use of a Proton pump inhibitors like Prevacid, Protonix
+Maybe a prostaglandin agonist like Cytotec or H2 antagonist like Zantac instead of a PPI
+Discouraging alcohol, NSAIDs, ASA

Question 21

Risk factors for development of stress ulcers

Answer 21

-large-surface area burns, trauma, sepsis, acute resp. distress syndrom, severe liver failure, major surgical procedures, zollinger-ellison syndrome

Question 22

risk factors for dev. gastric cancer

Answer 22

-genetic predisposition, carcinogenic factors in the diet, autoimmune gastritis, gastric adenomas or polyps

Question 23

conditions causing altered intestinal function

Answer 23

-irritablebowel disease, inflammatory bowel disease, diverticulitis, appendicitis, alteration in bowl motility, malabsorption syndrome, cancer of the colon and rectum

Question 24

infections of the intestine

Answer 24

-VIRAL INFECTION
  \+rotavirus
-BACTERIAL INFECTION
  \+clostridium difficile colitis
  \+escheichia coli O157:H& Infection
- PROTOZOAL INFECTION
  \+E. Histolytica

Question 25

characteristic of irritable bowel disease

Answer 25

-persistent or reccurent symptoms of abdominal pain, altered bowl function, varying complaints of flatulence, bloatedness, nausea and anorexia, constipation or diarrhea, anxiety or depression

Question 26

Inflammatory bowel disease

Answer 26

-CROHN DISEASE +Recurrent, granulomatous tpe of inflammatory response that can affect any area of the GI tract from the mouth to the anus -ULCERATIVE COLITIS + A nonspecific inflammatory condition of the colon

Question 27

symptoms of diverticulitis

Answer 27

-pain in the lower left quadrant, nausea and vomiting, tenderness in the lower left quadrant, a slight fever, an elevated while blood cell count

Question 28

Appendicitis

Answer 28

- the appendix becomes inflames, swollen, and gangrenous, and it eventually perforates if not treated - appendicitis is related to intraluminal obstruction with a fecalith ( hard poop), gallstones, tumores, parasites, or lymphatic tissue

Question 29

Types of diarrhea

Answer 29

-Large volume +osmotic, secretory -Small-volume +inflammatory bowel disease, infectious disease, irritable colon

Question 30

manifestation of classic form of celiac disease

Answer 30

-presents in infancy -manifests as +faulire to thrive, diarrhea, abdominal distention, occasionally, severe malnutrition

Question 31

common cause of constipation

Answer 31

- failure to respond to the urge to defecate - inadequate fiber in the diet - inadequate fluids - weakness of the obdominal muscles - inactivity and bed rest - preggers - hemorrhoids

Question 32

fecal impaction

Answer 32

- painful anorectal disease - tumors - neurogenic disease - use of constipating antacids or bulk laxatives - a low-residue diet - drug-induces colonic stasis, paralytic ileus - prolonged bed rest and debility

Question 33

INTESTINAL OBSTRUCTION

Answer 33

- mechanical obstruction can result from post operatice causes such as external hernia and postoperatice adhesions - paralytic, or adynamic, obstructino results from neurogenic or muscular impairment of peristalsis - mechanical (twist stool) - paralytic - abdominal distention, n/v, high pitch bowel sounds, no flatus, loss of fluids and electrolytes, may necessitate NG tube placement and/or surgery

Question 34

perotoneal caivty and perotonitis

Answer 34

-permits rapid absorption of bacterial toxins -favors the dissemination of contaminants -great inflammatory response (thick, fifrinous protective substance) -causes? +perforated peptic ulcer, ruptures appendixm perforated diverticulum, gangrenous bowel, PID, nangrenous gallbladder, abdominal trauma and wounds

Question 35

intestinal malabsorption

Answer 35

- failure to transport to dietary constituents from the lumen of the intestine to the extracellular fluid - Causes: Celiac disease - symptoms: diarrhea, steatorrhea, flatulence, bloating, abdominal pain, cramos, weakness

Question 36

colorectal cancers and testing

Answer 36

- age, family history, crohn disease, ulcerative colitis, diet - stool occult blood test, digital rectal examination, x-ray studies using barium, flexible sigmoidscopy and coloscopy