Gastric and Small intestine Motility Flashcards Preview

Physio U4 > Gastric and Small intestine Motility > Flashcards

Flashcards in Gastric and Small intestine Motility Deck (56)
Loading flashcards...
1

2 functional areas of the stomach

Orad and Caudad

2

Orad

fundus and upper portion; receptive relaxation to receive bolus, Adaptive relaxation to store chyme

3

Caudad

lower portion and antrum; regulates gastric emptying at a rate appropriate for digestion and absorption

4

Receptive relaxation (long neural reflex)

the orad stomach is highly compliant and can receive large volumes of food without increasing gastric pressure

5

Adaptive relaxation (short and long neural pathway)

the orad stomach relaxes when the caudad stomach is distended by gastric contents

6

adaptive relaxation promotes retropulsion by

providing a pressure gradient

7

Peristaltic contractions of the caudad stomach function to

mix chyme, emulsify fats, reduce food particle size, amd propel contents toward pylorus, delivery to small intestine at appropriate rate

8

Sieving (emptying the stomach)

pylorus opens and SMALL (<2mm) particles enter duodenum

9

Retropulsion

trailing contraction forces larger particles near pylorus through a small opening to forcefully break them up

10

Leading contraction

closes pylorus

11

trailing contraction

forces contents through small space with great pressure

12

Retropulsion function

mix gastric contents, reduce particle size, and emulsify fats

13

Factors that determine gastric emptying

motilities of stomach and duodenum, diameter of pylorus, composition of particles in the lumen of stomach and small intestine

14

Factors that increase gastric emptying

increased orad distention, increased caudad contractions, large pylorus diameter, increased PNS, decreases SNS

15

Factors that decrease gastric emptying

increased SNS, decreased PNS, duodenal distention

16

Particles in stomach - liquids

empty immediately

17

Particles in stomach - smaller particles <2 mm

empty faster than larger particles

18

Particles in stomach - peptides

increased gastrin = increased gastric emptying

19

Particles in duodenum

decrease gastric emptying via feedback inhibition

20

Particles in duodenum - Acidic chyme

H+ by secretin

21

Particles in duodenum - Fat

slows for digestion by CCK

22

Particles in duodenum - hypertonic chyme

long and short reflexes slow for reabsorption

23

How do particles in the ileum affect gastric emptying?

decreases it via long reflexes and GI hormones

24

Gastroparesis

impaired or delayed gastric emptying w/o obstruction

25

Causes of gastroparesis

Autonomic Neuropathy, vagotomy, and medications

26

Treatments for gastroparesis

small meals, viscous foods, low fat diet, protokinetic meds (erythromycin)

27

Diabetic with gastroparesis

erythromycin treatment

28

Type I diabetic eats meal high in fat, his insulin delivery should be

20% at beginning of meal, 80% afterwards

29

Function of phasic contractions in small intestine

mix chyme, expose chyme to enterocyte brush border for digestion-secretion, move chyme towards colon

30

2 types of phasic contractions in the small intestine during digestive period

segmentation and peristalsis