2. GI system

Question 1

What is the GI system for?

Answer 1

= designed to break down food into biomolecules that can be absorbed into the blood and transported for cells to use

Question 2

vomiting

Answer 2

= forceful emptying of the stomach contents and intestinal chyme through the mouth

Question 3

Physical alterations that lead to vomiting?

Answer 3

• vomiting centre is stimulated in brain which trigers the vomiting reflex

Cause:

• distension of the stomach or duodenum
• trauma to testes, ovaries, bladder or kidney
• provoked by occlusion of the coronary vessels, distension and the intestine and irritation of the gastrointestinal mucosa
• In the GI tract, mechanoreceptors in the intestinal wall are activated by abnormal contractions, distension or physical damage

Question 4

Clinical manifestations that may be in a patient who has being vomiting for several days

Answer 4

• GORD - because of the weakening of the lower oesophageal sphincter
• malnutrition - lack of food intake and absorption of nutrition
• dehydration
• anorexia

Question 5

Possible causes of Upper GI bleeding

Answer 5

• Peptic ulcer  helicobacter pylori
• Tears in the lining of the Esophagus
• Abnormal, enlarged veins in Esophagus
• Esophagitis
• Drug induced erosions
• Prolonged vomiting

Question 6

Complications that can result from upper GI bleeding

Answer 6

• aspiration
• pneumonia
• respiratory failure
• hypovolemic shock

Question 7

What are the physical alterations that can lead to increased gastric production?

Answer 7

• increased number of parietal/ chief cells
• decrease in the inhabitation of gastric secretions
• increased sensitivity to food e.g. caffeine and histamine
• excessive vagal stimulation

Question 8

What are the factors of decreased mucous production in the stomach?

Answer 8

• ischemia can lead to loss of integrity of mucosa
• sympathetic stimulation will decrease secretions
• bile or pancreatic enzyme reflux from duodenum
• alcohol consumption
• helicobacter pylori

Question 9

Treatments that could be used to alleviate symptoms observed in celiac disease and lactose intolerance?

Answer 9

Lactose intolerance - due to a deficiency in the enzyme lactate which breaks down lactose into its small component’s glucose and lactose

- Limit milk and dairy products - Include small serving of dairy products 
 - Lactose reduced foods 
  - Add a liquid or power lactase enzyme to milk to break down the lactose

Celiac disease = immune reaction to gluten

- only way to manage symptoms is to not eat gluten (gluten free diet)

Question 10

How does the stomach protect itself from its gastric acid?

Answer 10

= by secreting sticky, neutralising mucus that clings to the stomach walls

• if the layer becomes damaged in anyway it can result in painful and unpleasant stomach ulcers

Question 11

What is diarrhoea and name the two types.

Answer 11

= is the increase in the frequency of defecation, the fluidity and volume of faeces

1. osmotic diarrhoea
2. secretory diarrhoea

Question 12

What is the pathophysiology and the causes of osmotic diarrhoea?

Answer 12

= occurs when a substance in the intestine cannot be absorbed and instead draws water into the lumen via osmosis

• lactose deficiency - when ingested lactose cannot be digested and hence absorbed in the small intestine
• sorbitol - a non-absorbable synthetic sugar

Question 13

What is the pathophysiology and the causes of secretory diarrhoea?

Answer 13

= caused by excessive mucosal secretion of fluid and electrolytes, or inhibition of sodium chloride absorption

• bacterial endotoxins
• neoplasms (cancers) the produce hormones that stimulate intestinal secretion
• thyroid carcinoma
• IBS, ulcerative colitis, crohn’s disease