13. Gut flux and motility

Question 1

primary peristaltic wave

Answer 1

forces the bolus down the esophagus and into the stomach

wave lasts about 8–9 seconds

Question 2

secondary peristaltic wave

Answer 2

In the event that the bolus gets stuck

a secondary peristaltic wave occurs

forces the bolus further down the esophagus

waves continues until the bolus enters the stomach

Question 3

What part of the brain controls the process of peristalsis?

Answer 3

medulla oblongata

Question 4

5 Functions of the Fundus (Proximal stomach)

Answer 4

1) Gastro duodenal flow
2) Intragastric pressure
3) Temporary storage
4) Tonic motor activity
3) Stimulates propulsion

Question 5

What % of body weight does the pancreas represent

Answer 5

0.1%

Question 6

How may enzymes does the pancreas release?

Answer 6

15 digestive enzymes

Question 7

4 Functions of the small bowel

Answer 7

Lymphoid tissue
Absorption
Immune function
Digestion

Question 8

Where is Lymphoid Tissue concentrated

Answer 8

Terminal ileum

Tonsils

Question 9

3 Functions of the large bowel

Answer 9

Salvage of water and electrolytes

Absorption of undigested carbohydrates

Secretion of mucus

Question 10

How is the small bowel adapted for Immune function?

Answer 10

MALT (GALT) made up of B and T cells

Peyer’s patches (discrete clusters of immune cells)

Secretory IgA

Question 11

How is the small bowel adapted for Absorption

Answer 11

Microvilli = large S.A

Motility = allows contact of contents with absorptive surfaces

Question 12

Where is majority of iron absorbed?

Answer 12

Duodenum

Question 13

Where is majority of folate absorbed?

Answer 13

Jejunum

Question 14

Where is majority of B12 absorbed?

Answer 14

Ileum

Question 15

Where does majority of water absorption occur?

Answer 15

ascending and transverse colon

Question 16

What 4 factors determine Fluid Absorption?

Answer 16

Luminal Osmolarity
Motility
Mucosal Integrity
S.A

Question 17

Oral intake of fluid a day

Answer 17

2L

Question 18

Biliary fluid entering a day

Answer 18

0.5L

Question 19

Pancreatic fluid entering a day

Answer 19

1L

Question 20

Intestinal fluid entering a day

Answer 20

1L

Question 21

Gastric fluid entering a day

Answer 21

2.5L

Question 22

Salivary fluid entering a day

Answer 22

1.5L

Question 23

Fluid reabsorbed in to small intestine a day

Answer 23

7L

Question 24

Fluid reabsorbed in to large intestine a day

Answer 24

1.4L

Question 25

Treatment of FH (Familial Hypercholesterolaemia)

Answer 25

statins

Question 26

Classification of hyperlipidaemias | Fredrickson/WHO (1970)

Answer 26

Type I Increased CMs Type IIa Increased LDL Type IIb Increased LDL and VLDL Type III Increased Remnants and IDL Type IV Increased VLDL Type V Increased Chylomicrons and VLDL

Question 27

Familial Type III Hyperlipidaemia

Answer 27

Mechanism: defective remnant clearance Prevalence: 1 in 5000 Inheritance: autosomal recessive Physical Signs: striate palmar and tuberoeruptive xanthomata

Question 28

Familial Hypercholesterolaemia

Answer 28

Mechanism: LDL Receptor defect Prevalence: 1 in 500 Inheritance: Autosomal dominant Physical Signs: Tendon Xanthomata, corneal arcus

Question 29

Familial Combined Hyperlipidaemia

Answer 29

Mechanism: overproduction of VLDL and apoB Physical Signs: variable, Xanthelasmata Prevalence: 1 in 100 Inheritance: variable, some autosomal dominant

Question 30

Familial Hypertriglyceridaemia

Answer 30

Physical Signs: prone to pancreatitis and diabetes mellitus Prevalence: 1 in 300 Inheritance: variable

Question 31

post MI treatment

Answer 31

atorvastatin 80mg

Question 32

Statins mode of action

Answer 32

inhibit cholesterol synthesis increase hepatic LDL receptor activity

Question 33

Fibrates mode of action

Answer 33

activate PPAR alpha ↑ LPL activity ↑ biliary cholesterol secretion

Question 34

Bile Acid Binding Resins mode of action

Answer 34

divert cholesterol into bile acid synthesis interrupt enterohepatic circulation of bile acids ↑ hepatic LDL receptor activity

Question 35

Cholesterol Absorption Inhibitors mode of action

Answer 35

reduce enterohepatic cholesterol recycling

Question 36

PCSK9 Inhibitors mode of action

Answer 36

antibodies to PCSK9

Question 37

advantages of statins

Answer 37

potent mostly well tolerated single (nightly) dose

Question 38

disadvantages of statins

Answer 38

muscle toxicity hepatic toxicity may aggravate liver disorder

Question 39

advantages of fibrates

Answer 39

potent mostly well tolerated quite cheap

Question 40

disadvantages of fibrates

Answer 40

muscle toxicity ↑ incidence of gallstones potential for toxic interactions

Question 41

ezetimibe

Answer 41

used to treat hypercholesterolaemia used for patients intolerant to statins

Question 42

management of abdominal pain

Answer 42

NG tube Oxygen therapy Proton pump inhibitors IV fluids

Question 43

Likelihood of colorectal cancer in Ascending colon

Answer 43

30%

Question 44

Colorectal cancer Right Sided Lesion

Answer 44

Present later Less likely to cause diarrhoea May give rise to iron deficiency anaemia

Question 45

Colorectal cancer Left Sided Lesion

Answer 45

Present earlier More likely to cause a change in bowel habit More likely to obstruct

Question 46

How do you diagnose colorectal cancers?

Answer 46

Blood tests Examination and History Radiology Tissue diagnosis

Question 47

Pancreas protein producing capacity

Answer 47

13x protein producing capacity of liver

Question 48

Likelihood of colorectal cancer in Transverse colon

Answer 48

10%

Question 49

Likelihood of colorectal cancer in Descending colon

Answer 49

15%

Question 50

Likelihood of colorectal cancer in Sigmoid colon

Answer 50

25%

Question 51

Likelihood of colorectal cancer in Rectum

Answer 51

20%