lewis ch 38 - GI assessment Flashcards
4 layers of the stomach (inner to outer)
- mucosal: innermost
- submucosa connective tissue
- muscle (oblique, circular, longitudinal)
- serosa: outermost
“rest and digest” - cholinergic system
parasympathetic nervous system
“fight or flight” - anticholinergic system, decreases digestion
sympathetic nervous system
major nerve that supplies blood to the GI tract and controls GI movements
auerbach plexic (myenteric)
system that regulates motility and secretion along entire GI tract, can function independently of CNS
enteric nervous system (ENS)
3 arteries that bring blood to the GI system
- celiac artery: stomach and duodenum
- superior mesenteric artery: distal small intestine to mid-large intestine
- inferior mesenteric artery: distal large intestine through anus
what does the liver do in relation to the GI system
GI tract organs empty into hepatic vein which goes to the liver - liver cleans blood of bacteria and toxins from GI tract
what percent of cardiac output does GI tract receive at rest? after eating?
25-30% at rest
35+% after eating
lining of abdominal cavity walls
peritoneum
lining of abdominal organs
visceral layer
3 purposes of the GI system
- ingestion
- digestion
- absorption
hormone involved in appetite suppression
leptin
hormone involved in appetite stimulation
ghrelin
what can inhibit appetite (5)
- stomach distention
- illness (with fever)
- hyperglycemia
- N/V
- certain drugs (amphetamines)
3 divisions of pharynx
nasopharynx
oropharynx
laryngeal pharynx
what does the lower esophageal sphincter prevent
reflux of acidic gastric contents into esophagus
functions of stomach (3)
- store food
- mix food with gastric secretions
- empty contents in small boluses into small intestine
functions of small intestine (2)
- digestion and absorption
- uptake of nutrients from gut lumen to bloodstream
two types of cells found in the fundus of the stomach
chief cells
parietal cells
what do chief cells secrete
pepsinogen
what do parietal cells secrete
secrete hydrochloric acid, water, and intrinsic factor
where is protein broken down (and by what)
broken down by pepsin in the stomach
where are carbohydrates and fats broken down
in small intestine
where does most absorption occur
small intestine
what are the three sections of the small intestine
duodenum
jejunum
ileum
4 sections of the large intestine
cecum
colon
rectum
anus
what does the large intestine absorb (2)
water and electrolytes
what does the large intestine produce (2)
Vitamin K
some B vitamins
in what patients would the valsalva maneuver be contraindicated (6)
- head injury
- eye injury
- heart problems
- hemorrhoids
- abdominal surgery
- liver cyrrhosis with portal hypertension
describe the valsalva maneuver
- patient holds breath and contract abdominal muscles
- reduces venous flow to heart
- decrease in cardiac output and bp drops
- patient relaxes
- sudden blood flow to heart, increased heart rate, bp rises
what is the largest internal organ
liver
what is the functional unit of the liver
lobule
cells found in liver that carry out phagocytic activity, removing bacteria and toxins from blood
kupffer cells
what form is bilirubin when its released into the bloodstream and binds to albumin
unconjugated bilirubin
what form is bilirubin when its in the liver and combined with glucoronic acid as it is excreted as bile into intestine
conjugated bilirubin
purpose of gallbladder
collects and stores bile (around 45 mL)
exocrine function of the pancreas
contributes to digestion through release of enzymes
endocrine function of pancreas
alpha cells in islet of langerhans secrete glucagon
what do the beta cells in the islet of langerhans secrete
insulin
amylin
aging adult considerations relating to GI system
- loss of teeth
- decreased number of taste buds
- decreased appetite
- decreased sense of smell
- less saliva
- delayed emptying of esophagus
- decreased HCl acid secretion
- constipation
- liver size decreased
- gallbladder size decreased
what is xerostomia
decreased saliva
what are the four enzymes of the liver
ALT
AST
ALP
GGT
normal ALT levels
4-36 U/L
normal ALP levels
30-120 U/L
normal GGT levels (men and women over and under 45 yo)
male and female >45 yo: 8-38 U/L
female <45 yo: 4-27 U/L
normal AST levels
0-35 U/L
what is a normal prothrombin clotting time
11-16 seconds
