Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology GI > Physiology 2.5.14 GI Vomit and Defecation > Flashcards

Physiology 2.5.14 GI Vomit and Defecation Flashcards

1
Q

Net aboral movements of contents (how uch enteres and leaves)

A

500-600cc enter/day

150 cc leave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Waht are the muscular layers of the large intestine

A

Inner circular laer with outer longitudinal layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how are outer longtifuindal layers arranged

A

as three bands caleld taeniea coli

They run to rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Longitudinal layers from rectum to anus?

Internal anal sphinter!

A

it is continous

Circular muscle thickens at anal canal to beocme the internal anal sphincber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

External anal sphcinter

A

Overlapping and goign distal to internal anal sphincter are layer sof striated msucle which make up external anal sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Haustra

A

cotractions of circular muscle divide colon into segments called haustra

Reform elsewhere on colon (haustrations)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

PS innervation of 1st half of colon

A

by vagus

Sympathetic from SUPERIOR MESENTERIC GANGLION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

PS innervatio nof caudal half of colon

A

Pelvic nerve PS pereganglioinc fiber

Sympathetic from INFERIOR MESENTERIC GANGLION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Innervation of rectum and anal canal

A

Sympathetic fibers form Hypogastric Plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

INnervation of external anal sphincter

A

Somatic fibers of Pudendal Nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are examples of Osmotic mechanisms of diarrhea

A 
Lactose intolerance
sea water
MgSO4
Steratorrhea
Post-prandial dumping syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are secretory causes of diarrhea

A

Bacterial toxin
Cholear (cAMP mediated Cl- secretino)
Enteropathic E. coli (Increase intracellular concentration)

Gastrinoma

VIPoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are malabsorptive cuases of Diarreha

A

Bile acid malabosrption

Gluten enteropahty (Celiac Disease)

Cholelithiasis (gall stones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

exudative causes of diarreha

A

invasive organisms
Salmonella, amoeba histolytica, with inflammation and blood loss
Influenzea, Crohn’s Disease (ileitis)
Ulcerative colitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Excess motor activity cuases of diarreha

A

Irritable Bowel
bacterial action on unabsorbed long-chain FA
Stress

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Results of Chroniic Diarrhea (6)

A
  1. Dehydration
  2. Hypokalemia
  3. Acidosis (loss of HCO3-)
  4. Loss of water soluble vitabmins
  5. Possible loss of Ca2+
    6 Possible loss of fat soluble vitamins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Hirschprung’s Disease/Megacolon, denervation

A

Severe constipation is seen in concentinal megacolon

Absencse of ENS in teh internal anal sphcinger and often rectum

Denervated are has increased tone
NO PROPULSIVE ACTIVITY

Colon proximal to diseased area becomes grossly distended

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is Irritable colon syndeome,

A

Increased/decreased signmoidal segmentation

Common in audlts

Abdominal pain is couple with either constipation or dirrhea

Stress produces increased sigmoidal segmentation and constipation in some people

Others, decreased sigmoidal segmenation and diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does stress induce irritable colon syndrome

A

Stress produces increased sigmoidal segmentation and constipation in some people, in others, decreased sigmoidal segmentation and dirrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the mechanism of Diverticula?

A

in older adults, outpoucing of the mucosa thorugh the uscular wall fo teh colon can develop. These are called diverticular and may be due to chornic high intraluminal pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the phases of vomiting

A
  1. Nausea
  2. Sympathetic discharge
  3. Unuusal motility
  4. Retching
  5. Stop respriation (valsalva aneuoer with Explusion/emesis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the driving force for expulsion

A

Contraction fo the abdominal wall and diaphragm skeletal muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are possible complications of vomiting/emesis (4)

A
  1. Aspiration
  2. Dehydration/Electrolycte Imbalance (hypokalemic alkalosis(
  3. Mallory-Weiss tear (bleeding)
    4Dental Enamel Erosion
24
Q

What are the sites of stimulus origin (4)

A

Chemoreceptor Triger Zone (CTZ)

2 Vestibular system

  1. Irritation of Pharynx
  2. Irritation of GI Tract
25
CTZ - location what stimulates it
Floor of 4th ventricle, area postreme= circumventricular organ outside the BBB Stimulated by BB chemicals What kind of receptors present at CTZ
26
What receptors are in CTZ
1. Dopamine, D2 2. Serotonin 5-HT3 R 3. R for opioids, Ach, 4. and, in hte ifnal common pathway to vomiting center, Substance P receptors
27
Irritation of pharynx. how?
Gag reflex
28
Irritation of GI tract
In enteric plexus and up Vagus N Chemotehrapy, radiation, distention of acute infectious gastroenteritis vis 5HT3 receptors
29
Mechanics of retching
1. Duodenal contents are forced into stomach by spasm of duodenum. Antrum is also in spasm ,but the body of the stomach and LES are relaxed inspiration against a partially closed glottis loweres intrathoracic pressure, and contraction of abdominal muscles raises intra-abodminal pressure Pressure gradient from abdomen to thorax foreces contents of body of stomach into esopahgus Hypopharyngeal spcinceter remains closd, and secondary peristaltic waves in esophagus force its conents back onto stomach Cycle repeated
30
What parts f GI is in spasm during retching? HOw does this affect intra-abdominal pressure
Antrum and duodenum in spasm Leads to high intraabdominal pressure
31
What parts of GI are relaxed
Body of stoach and LES relaxed Low intrathoracic pressure
32
Is the hypoharygeanl sphicner open or closed?
closed! , and seconary peristatlitl waves in esopaghus force conents back into stomach
33
What is the mechanics of vomiting
Vomiting buidls on a developed retch Antrum and duodenum in spasm, but body of stomach and lower esophageal sphincter are relaxed Strong contractions of abdominal muscles force the contents fo the stoamch into the esophagus and through the relaxed hypopharyngeal sphincter Strong expiration with a closed glottis raises intrathoracic pressure, and exerts pressure on esopahgus Events occur sequentially, first in abdomen, then in thorax There may be reverse peristaliss in teha ngrum of the stomahc, but there is no rverse peristaliss int eh body of stomach of esophagus both of which are relaxed
34
If vomiting somatic or autonomic
highly integrated chilefly somatic act
35
Describe vomiting innercation
Visceral motor activity prepares GI tract for efficent expulsion of vomitus THe expulsvive force is supplied by skeletal muscles whent eh diaphragm contracts sharply (descends); similar conraciton of abdominal musculature takes place
36
What can activate central or peripheral receptors
Motion sickeness Increased intracranila P Mental/higher CNS centers
37
What activates CTZ: floor of IV ventricle (area postrema0) cia
vestibular app, blood borne, emetics, CuSO4, digitalis, apomorphine and irradiation
38
What GI receptors activate vomiting center
Back of throat, increased stomach or duodenal pressure or certain cemciasl in duodenum (ipecac or CuSO4)
39
Categories that cause vomiting (6)
``` GI Sensory system and brain Metabolic Disturbances Pregnancy Drug Reactions Illenss ```
40
wha a GI problems that can lead to vomiting
irritation fo GI tract gastritis (viruses), gastroeneritis Pyloric stenosis--> Proejctile vomiting Bowel obstruction, distension, overreating (acute abodmoen, peritonitis, ileus) Food alelrgeies, cholycysttit, pancreatitis, appendicitis, hepatities Food poising Lactose intolerance
41
Sensory system in brain
``` Movements in motion sickeess Menier's syndome Concussion Cerebral heorrhage migrain brain bumors (can lead to chemoR imbalance, benig interacranial hypertension and hydrocephalus ```
42
Metabolic disorders that lead to vomiging
``` Hypercalemia Uremia Adrenal insufficienly Hypoglycemia Hyperglycermia ```
43
Pregnancy leads to vomiting
Hyperemesis: mornign sickness
44
Drug reactions to vomigitn
alochol opioids slective serotonin reupatek inhibitors chemotheryapy drugs
45
What are exampels of emetics
ipecaa salt water mustart water morphine digitalis glycosides
46
What are antiematices
Inhibit R Anticholinergics, anitihistamines Domaine serotnone antagonista sn acannabinoids Pt may need IV fluids
47
What is the resting pressure of ileocecal sphincter
20-40 mm HG exists
48
What does distension of ileum lead to for pshcincters
Distension of ileum leads to spchinceter realxation for flow of contents from ileum to oon
49
What happesn when distension in colon
Contraction fo sphcinger to prevent passage from colon to eleum
50
What happens to internal and external sphcincer when incras in rectom
Decrease in P in internal sphincter Increase in P in external anal Wsphcincter
51
What is mechanism of defecation (6)
1. Adequate stimulus is increased tension in teh rectal wall 2. Peristalsis and straightening of sigmoid colon plus rectal contraction 3. Relaxation of internal anal sphincter (PS via sacral cord) as rectal conraction reaches it 4. Descending colon contractions 5. VOLUNTARY increase in intrathoracic and intraabdominal pressure 6. Voluntary realxaion of external anal schincer, a striagted muscle (DEFECATION)
52
what is mass movement
strong peristaltil movement originating as high as transverse colon pushes colonic contents downard with sigmoid conents forced into rectum
53
What happnes when ther eis stretch and tension in walls of rectum
activate stretch receptors afferents form receptors go to defecation center in SACRAL CORD to initiate defecation SM internal anal spchinceter realxes nd sk musle external spchincter contracts
54
Are efferent pathways for defecationPS or Symp
purealy PS
55
Voluntary inhiition of defecation
produces song contractions of striated muscles of pelvic diapghragm and exrnal anal sphincter Motiliy of entire colon is dperessed
56
What happens when feces remains in rectum for a long time
rectu relaxes which decreases wall tension thereby removing stimulus and urge to defecate rectum conetents evacuated backward, with retropulsion into sigmoid colon which as a lower level of motor activity

Physiology GI (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions