Term | Definition |
fundus of stomach | storage |
antrum of stum | mixing |
function of the stomach | converts food to chyme |
accessory organs of the GI system | teeth, tongue, salivary glands, liver, gallbladder, pancreas, & appendix |
functions of mouth | food enters, digestion begins, hydrolysis (salivary breakdown forms a bolus (food ball)) occurs, chewing, & swallowing |
fxn of upper esophageal sphincter | keeps air from entering tube |
chyme | semisolid mixture that moves on to SI |
small intestine | most fxn in duodenum & jejunum; ileum responsible for transport; first place nutrients are absorbed |
large intestine | term end of digestive tract; any undigested/unabsorbed food material enters the lg intestine; drying of feces as water & salts are absorbed & storage of feces; leftover material is acted upon by bact |
4 basic digestive processes of the stomach | motility, secretion, digestion, absorption |
motility | filling, storage, mixing, emptying |
storage | food is stored in the bod of the stomach; fundus contains only a pocket of gas; muscs in antrum are thicker & stronger in order to mix |
factors that influence rate of gastric emptying | strength of contraction, amount chyme in stomach, the presence of fat, acid, hypertonicity, or distension in the duodenum; |
mucosal lining of the stomach | protective barrier |
3 phases of control of gastric secretion | cephalic phase, gastric phase,& intestine phase |
cephalic phase | feedforward prod of HCL & pepsinogen by stimuli acting in the head even b4 food reaches stomach; incr in gastric secretion by vagal nerve; starts b4 food is even in mouth |
gastric phase | food reaches stomach: protein in stomach stims release of gastrin==> HCL & pepsinogen secretion |
Intestine phase | inhibitory phase: shuts off the flow of gastric juices as chyme begins to empty into small intestine |
role of HCL | activates the enzyme precursor pepsinogen to an active enzyme pepsin; provides an optimum environment for pepsin act (acidic); denatures protein; kills most of micro-organisms ingested with food |
two non-nutrient substances absorbed in stomach | aspirin & alcohol |
segmentation | mixes & propels chyme via pacesetter cells in the sm intestine; ringl9ike contractions initiate peristalsis |
migrating mobility complex | int house=keeper; pushes out any remaining food |
achalasia | failure to relax the smooth musc of the GI tract, especially in the lower esophageal sphincter |
factors that decrease LES Pressure | foods, caffeine, alcohol, CNS depressant meds, systemic scleroderma |
factors that increase gastric pressure | high-protein food, obesity, tight clothes |
types of gastritis | acute gastritis (hemorrhagic or erosive, associated w/ serious illness & various meds (NSAIDS))); chronic gastritis (asymptomatic) |
chronic gastritis | Type A: chronic fundal gastritis (less common, pernicious anemia, occurs w/ autoimmune dz's); Type B: more cmn, chronic bact infection, H. pylori |
acute gastritis | epigastric pain, abd distension, loss of appetite, v/n, low grade fever, |
dx of gastritis | confirm presence of H. pylori by urea breath or stool antigen test |
pyloric stenosis | projectile vomiting at birth; firm, palpable nodule in RUQ |
gastric adenocarcinoma | attributed to H. pylori bact; contributes to 90% of stomach tumors; common location: lesser curvature of prepyloric antrum; asymptomatic early on; postop chemo ineffective; palpation of L supraclavicular lymph node |
peptic ulcer | a break in the protective mucosal lining exposing submucosal areas to gastric secretions; damage to musculature, resulting in scar tissue; 3 types: gastric ulcers, duodenal ulcers, & stress ulcers; usu due to H. pylori & excessive prod of acid |
gastric ulcer | lining of stomach; usu at lesser curvature on post wall |
duodenal ulcer | usu in duodenal bulb or cap (closest portion of duodenum to the stomach) |
stress ulcer | painless until perforation or hemorrhage; upset to aggressive-defense balance (sympathetic response) & ischemia to gastric mucosa |
classic symptoms of peptic ulcers | epigastric pain described as a burn, cramp, or ache near the xiphoid process |
antisecretory drugs | decrease acidic secretions |
vital signs signaling bleeding | SBP under 100 mmHg, pulse rate >100 bpm, & drop of 10 mmHg or more in DBP |
upper GI | consists of mouth, esophagus, stomach, & small intestine |
esophagus | food formed into a bolus |
lower GI | cecum to anus (includes appendix) |
fistulae | abnormal connections between organs |
preparation for lower GI tests | dietary changes (low fiber diet 2-3 days b4), no smoking, no meds, laxatives, & inform MD if insulin pump |
fecal occult blood test | detects presence of microscopic or invisible blood in feces; blood in stool may be only symptom of early colorectal CA; to determine cause of anemia; usually want to take multiple tests: 3 diff tests on 3 diff days for intermittent bleeding |
melena | black, tar-like BM, indicating CA |
stool culture | can detect presence of dz-causing bact or infection of digestive tract |
Imaging studies | injury or trauma in pelvic area, difficult w/ urinating/defecating, CA in pelvic & abdominal organs, infertility, an undescended testicle |
barium enema | examines rectum, lg intestine, & the lower part of the small intestine; metallic compound outlines stomach, intestines, etc... |
defecography | evaluates completeness of stool elim, id's anorectal abnormalities, & evals rectal musc contractions & relaxation; |
colorectal transit study | aka Sitzmark's test; x-ray imaging test that shows how well food moves through the colon; through swallowing capsules containing x-ray markers |
laparoscopy | used to directly visualize abdominal & pelvic organs when a pathological condition is expected; colectomy & appendectomy improve; |
irritable bowel syndrome (IBS) | most cmn disorder of the GI system; a group of symptoms; no inflammation; affects colon & SI; a fxn'l disorder, not due to structural or biological probs; altered GI motility, visc hypersensitivity, altered processing of info by nervous system |
IBS Cont... | abnormal intestinal contractions due to stress & chems in food; 3 mos of abdominal pain & at least 3 of the following sxs: bloating, passage of mucus, changes in stool form, stool freq alterations, difficulty passing bowel; LLQ pain |
inflammatory bowel dz (IBD) | Crohn's Dz & Ulcerative Colitis; body's inability to detect self-antigens from foreign antigens; inappropriate immune response; |
Crohn's Disease | can affect all wall layers, but w/ normal layers in between; accumulation of intestinal content breaches mucosal barrier resulting in chronic inflammation; narrows intestinal lumen; incurable |
ulcerative colitis | no normal layers btwn damaged layers; damages mucosa & submucosal chronic diarrhea, rectal bleeding w/ ulcerations, lg intestine primarily affected; abscess formation, necrosis; cured by colon resection |
PT considerations for CD & UC | back pain, RLQ pain, psoas abscess can cause pain & antalgic gait, joint involvement due to TNF (CD), anytime pt has low back, hip, pelvic, or SI pain for no reason, |
colorectal cancer | increased risk in men 40+; high mortality rate b/c no early screening tests; Risk factors: sedentary lifestyle, diet, obesity, UC, CD, other cancers, adenometous polyps; asymptomatic until metastasis; incr'd physical activity helps prevention |
carcinoembryonic antigen (CEA) | tumor marker for GI CA's, esp in advanced & recurrent CA's |
Diverticular Dz | diverticulosis (stage 1) & diverticulitis (stage 2); risk factors: low fiber diet, chronic constipation, weakness or atrophy of bowel muscle, |
diverticulosis | herniation of mucosa & submucosa through muscular layers (diverticula); bld supply decr'd; common, everyday, asymptomatic phase; incr'd urgency to defecate |
diverticulitis | inflammation of diverticula due to entrapment of food & feces; most common in sigmoid colon; rarely reversible; constipation & diarrhea, fever, rectal bleeding, anemia, & if chronic, obstruction & bowel perferation |
malabsorption diseases | celiac dz, CF, CD, pancreatic carcinoma, pernicious anemia (B12), short gut syndrome |
malabsorption diseases | celiac dz, CF, CD, pancreatic carcinoma, pernicious anemia (B12), short gut syndrome; early sxs: depression, abd bloating, prod of bulky, malodorous oil stools; flatulance; late sxs: low bp, infertility |
appendicitis | inflammation results in necrosis & perforation; peak incidence in men; acute pelvic pain in fm's; |