26 - GI Flashcards Preview

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Flashcards in 26 - GI Deck (25)
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1
Q

_ occurs when stomach acid used for digestion repeatedly backs up, or refluxes, into the esophagus

A

gastroesophageal reflux disease - GERD

heart burn/ chest pain - symptom

can lead to tooth erosion

2
Q

normal reflux is normal but not repeated episodes

low pH in stomach is okay - why?

esophagus not okay

A

secretion from mucous cells create a mucous layer with trapped bicarbonate that serves as a buffer

Paritetal cells - HCl acid

Mucous secreting cells - trap Bicarb
Immediate enviroment where cells are - pH is higher

Inner - lower pH

3
Q

GERD is caused by _ acid reflux- the backup of stomach acid or bile into the esophagus
_ most important factor/mechanism for preventing reflux

A

frequent, repeated

lower esophageal sphincter (LES)

esophagus - muscular tube - LES is a specialized ring of muscle that surrounds the most distal end of esophagus where it joins the stomach

active most of the time - contracting and closing off the passage

4
Q

Major causes GERD

A

Hiatal hernia - LES lines up with diaphragm and stomach -No longer at the level of the diaphragm - pressures no longer addictive - so reflux more easily

abnormalities in LES fxn - weak contraction, or relaxation (most common after meals), laxity of LES (opens more than should)

defects in esophageal contractions - swallows should eliminate acid (peristalsis down)

5
Q

minor causes of GERD

A

defects in emptying of stomach

excess production of acid - least likely cause

Least likely reason for heart burn - too much acid - THE LOWER ESOPHAGEAL SPHINCTER - major cause

6
Q

symptoms of GERD are treated with drugs that either _ intragastric acidity or _ gastrointestinal mucosal defense

A

reduce intragastric acidity or

promote gastrointestinal mucosal defense

7
Q

pharm intervention for GERD symptoms

gastrin’s role

directly and indriectly

the most important pharm intervention for GERD

A

gastrin stims parietal cells secrete H+ via H/K ATPase

indirectly via binding onto CCK2/gastrin receptors on ECL cells in the stomach , hich then responds by releasing histamine - which stims more HCL secretion

8
Q

not as important pharm for GERD but here

stims parietal cells secrete H+ via H/K ATPase
_ via parasympathetic innervation

A

Acetylcholine

not important

9
Q

_ stims parietal cells secrete H+ via H/K ATPase

acting on H2 receptor

A

histamine

H2 antagonist

Doesn’t work for Ulcers (bc ulcers are usually an infection)

Affects interaction with LIDOCAINE
Inhibits metabolism of lidocaine - might make it stick around longer

10
Q

pharm intervention to lower intragastric acid levels

3

A

gastrin -major - 2 path - most important PPI proton pump inhibitors - irreversible

histamine - major
acetylcholine - minor

11
Q

Peptic Ulcer disease - results from Helicobacter Pylori infection
Can give _ and it is treated

A

antibiotics

12
Q

drugs used to treat gastric acid and treat peptic ulcer disease

A

H+/K+ ATPase inhibitors - most effective

H2 antagonists

proglumide - gastrin antagonist = Less important- has effects + on opioids

antacids - neutralizes the stomach acid into water and salt - can’t reallt get above 4-5pH with these

13
Q

CNS - brainstem _ center coordinates motor activities after input from the chemoreceptor trigger zone

A

vomiting brainstem center

14
Q

drugs used to treat _ and _

receptor antagonists on the higher order areas - cerebral cortex, peripheral

D2 receptors, 5-HT3, neurokinin 1, opioid for _

mAcCH receptors, H1 receptors

A

vomiting and nausea

cancer chemother for d2 serotonin opi

motion sickness for H1

cannabis - acts on medulla

15
Q

_ laxative

act on enteric nervous system and colonic electrolyte and fluid secretion

anthraquinone derivatives - Aloe, senna, and Cascara - occur naturally in plants - porrly absrobed

6-12 hrs when given oral
2hr rectally

chronic used leads to brown pigmentation of colon known as melanosis coli

A

stimulant laxatives

increase peristalsis via intestinal nerve stimulation and most important cause accumulation of water and electrolytes in lumen by altering the absorptve and secretory activity of the muscoal cells

16
Q

_ laxatives

act like detergents for stool
anionic detergents reduce surface tension

allow intestinal fluids and fatty substances to penetrate the decal mass

A

decal softeners and lubricants

lubes like mineral oil coat the intestinal contents - preventing the abs of fecal water

17
Q

_ laxatives

increase water retention, which increases intraluminal pressure and stimulates peristalsis

A

osmotic laxatives

saline cathartics - salts that are poorly absorbed

non-saline cathartics - glycerol, sorbitol, polyethylene glycol

18
Q

_ laxatives

are not digested by absorb water and expand, increasing the bulk and moisture content of stool: peristalsis increases, and absorbed water softens the stool

A

bulk forming laxatives

synthetic fibers and natural plant products

19
Q

polyethylene glycol moity used to treat _

does not cross BBB

A

opioid induced constipation

20
Q

antidiarrheal agents work in 1 of 3 ways

A

soak up excess water - increase viscosity

anti-secretory in gut

decrease intestinal motility - give body more time to absorb luminal water)

21
Q

Kaolin - an absorbent 0 complex clay like compount - not used in humans

A

antidiarrheal agent

22
Q

_ antidiarrheal

inhibits PGs and Cl secretion (salicylate part)

also protects mucosa (coatings)

antisecretory, anti-inflammatoy, binds and absorbs bacterial and viral enteropathogens

A

mismuth subsalicylate

peptobismol

23
Q

_ antidiarrheal

inhibits peristalsis, reduces fecal volume and loss of fluid and electrolytes

adverse effects 0 dry mouth, and pain, constipation, dizziniss/drowsiness

A

opioids

24
Q

Diphenoxylate - antidirrheal opioid

abuse potential diminished by adding _

A

atropine

ioperamide - imodium - different drug - stays in GI tract non in brain

25
Q

no evidence of damage or diseas

a group of symptoms treated with diet and bulking agents

anti cholinergics for cramps

no great tx’s

A

Irritable Bowel Syndrome - IBS

increase fiber,