Session 1 - Purpose Of The Gut

Question 1

Which areas of the GI mechanically disrupt food?

Answer 1

Mouth/Teeth
Muscular stomach (especially lower area - strong peristaltic contractions, due to thicker distal muscle)

Question 2

Describe the muscular layers of the stomach wall

Answer 2

1. Longitudinal outer layer
2. Circular middle layer
3. Oblique inner layer

Smooth Muscle

Question 3

What are the main functions of the stomach?

Answer 3

1. Distend to STORE food (we eat quicker than we can digest)
2. Mechanically disrupt (muscle)
3. Chemically break down (H+, enzymes)

Question 4

Broadly, what defences does the GI have against pathogens?

Answer 4

Saliva (IgG)
HCL
Liver - kupffer cells
Peters patches (ileum)

Question 5

What is haustral shuttling

Answer 5

slow, uncoordinated movements of chyme from one Haustrum to another in the Colon.
(Haustrum - pouch of colon)

Question 6

What is a Haustrum?

Answer 6

Small pouches of the colon caused by sac formation, giving the segmented appearance.

Question 7

Which features of the gut give a large surface area for absorption?

Answer 7

The long length.
Many folds.
Villi and Microvilli

Question 8

What is the gastrocolic reflex?

Answer 8

One of many physiological reflexes controlling gut motility and peristalsis of the GI tract.

> Motility in response to stomach stretch, and byproducts of digestion in SI.

Question 9

Name the different sites of the GI tract in order, from mouth to anus.

Answer 9

Mouth
Oesophagus
Stomach
Duodenum
Jejunum
Ileum
Caecum
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
Rectum
Anus

Question 10

What is the function of the upper and lower oesophageal sphincters?

Answer 10

Upper
Just below oropharynx, prevents air entering GI.

Lower
Helps prevent reflux of stomach contents into oesophagus

Question 11

Which part of the GI are most of the nutrients absorbed?

Answer 11

Jejunum

Question 12

Where is most water absorbed in the GI?

Answer 12

Ileum

Question 13

What is the definition of peritoneal cavity?

Answer 13

Space between the parietal and visceral peritoneum

Question 14

What is it called where there is a DOUBLE fold of peritoneal cavity (around an organ)

Answer 14

Mesentry

Arteries, veins & lymphatic drainage etc.

Question 15

What is in the peritoneal cavity?

Answer 15

Nothing but small amount of fluid

Question 16

What are abdominal structures NOT supported in the peritoneum referred to as?

Answer 16

Retroperitoneal

Lie behind the peritoneum

Question 17

What is endoscopy?

Answer 17

Visualisation, biopsy taking, or therapeutic treatment of part of the GI tract using an endoscope, containing a camera.

Question 18

What condition commonly affects the junction between oesophagus and stomach?

Answer 18

Chronic acid exposure - reflux.

Barrett’s oesophagus

Question 19

Which common condition is visualised in the stomach during endoscopy?

Answer 19

Gastric ulceration.
Often benign, irregular border can signal malignancy
(Biopsy is mandatory)

Question 20

Which common condition may be found in the duodenum during endoscopy?

Answer 20

Duodenal ulcers common in 1st part.

Question 21

Why may an anterior duodenal ulcer be more serious?

Answer 21

Thinner unprotected wall, with less mucus protecting it.

Anterior ulcer may perforate causing peritonitis.

Question 22

What may be a complication of a posterior duodenal ulcer?

Answer 22

Erosion into gastroduodenal artery, which may cause massive haemorrhage and bleeding.
(Or into pancreas - severe pain)

Question 23

What is ERCP, what could be found?

Answer 23

Endoscopic retrograde CholangioPancreatography.

Common obstruction of the bile duct, causing jaundice (bilirubin cannot be removed)

Question 24

What may cause obstruction of the bile duct?

Answer 24

-Painless obstruction
Usually secondary to a tumour. (E.g. carcinoma of pancreas, bile duct cancer, etc)

-Painful obstruction
Usually due to gallstone.

Question 25

What congenital condition may be found in a small bowel endoscopy? What complications could arise?

Answer 25

Meckel’s Diverticulum
Congenital diverticulum.

• 2ft from ileocaecal valve.
• 2% of population
• 2 inches long (roughly)

Could contain acid secreting gastric mucosa, cause bleeding/ inflammation.

Question 26

Name some commonly found abnormalities in a colonoscopy.

Answer 26

Diverticula
Cancers - especially in caecum and ascending.
Haemorrhoids etc.