Upper GI Tract Flashcards
How is the motility of the oesophagus determined?
By pressure measurements (manometry).
Peristaltic waves are around 40 mmHg.
What is the LOS resting pressure and how does that change during receptive relaxation?
-Resting pressure is 20 mmHg
-Decreases by <5 mmHg during receptive relaxation
What is receptive relaxation and what mediates this?
Receptive Relaxation refers to the muscular relaxation of the orad stomach in response to entry of food from the esophagus.
Mediated by Inhibitory noncholinergic nonadrenergic (NCNA) neurones of myenteric plexus
What is a functional disorder of the oesophagus?
Presence of an oesophageal stricture (abnormal narrowing of oesophagus)
What are some causes of Oesophageal strictures?
Abnormal oesophageal contraction:
-Hypermotility
-Hypomotility
-Disordered coordination
Failure of protective mechanisms for reflux:
Gastro-Oesophageal Reflux Disease (GORD)
What is dysphagia?
Difficulty in swallowing
What types of dysphagia are there?
- For solids and fluids
- Intermittent or progressive
- Precise or vague in appreciation
What is odynophagia?
Pain on swallowing
What is regurgitation?
- Return of oesophageal contents from above an obstruction
- May be functional or mechanical
What is reflux?
Passive return of gastroduodenal contents to the mouth
Define achalasia.
- Hypermotility of oesophagus due to loss of ganglion cells in Aurebach’s myenteric plexus in LOS wall
- Leads to decreased activity of inhibitory NCNA neurones
What does decreased activity of inhibitory NCNA neruones lead to?
- Increased resting pressure of LOS
- Receptive relaxation sets in late and is too weak so during reflex phase the LOS pressure is much higher than stomach
- Swallowed food collects in oesophagus causing increased pressure throughout with dilation of oesophagus
- Propagation of peristaltic waves cease
What is primary achalasia?
The most common form of achalasia
aetiology is unknown
Diseases causing oesophageal motor abnormalities similar to primary achalasia described as what?
Secondary achalasia
In this image of a patient with achalasia, what can be used to describe the appearance of the esophagus.
Birds beak appearance,
can see tapering of the distal esophagus
What happens to the resting pressure in achalasia?
Increased resting pressure.
What is the onset of achalasia described as?
Insidious onset.
What is seen in this x ray?
Pneumomediastinum
What is the definitive solution for an oesophageal perforation?
Oesophagectomy.
What 3 mechanisms defend against reflux?
-Volume clearance, peristalsis reflex
-pH clearance, saliva
-Epithelium barrier properties
What kind of hernia can be seen here?
Sliding hiatus hernia
What kind of hernia can be seen here?
Rolling hiatus hernia
What are the two standard investigations we do for anyone with GORD?
-Oesophageal manometry
-24-hr oesophagel pH recording
What is an oesophageal manometry
Oesophageal manometry is a diagnostic test used to evaluate the function of the muscles in the oesophagus
What do the cardia and pyloric regions of the stomach secrete?
Mucous only
What does the body and fundus of the stomach secrete?
Mucous, HCL, pepsinogen
What does the antrum of the stomach secrete?
Gastrin
What is gastritis?
Gastritis is a medical condition characterized by inflammation of the lining of the stomach.
What can be a cause of erosive & haemorrhagic gastritis.
Acute ulcer
What causes chronic non erosive active gastritis and where does it affect?
Helicobacter pylori, affects the antrum.
What is the name of the gastritis that affects the fundus/ fundal gland?
Atrophic gastritis
What causes atrophic gastritis and what does it lead to?
Autoantibodies attacking parts and products of parietal cells,
leads to decreased acid and IF secretion.
What is also seen in patients with atrophic gastritis in regards to IF?
Vitamin B12 defficiency leading to megaloblastic anaemia.
What endocrine factor stimulates an increase in acid secretion?
Gastrin
What paracrine factor can also stimulate acid secretion?
Histamine
Which cells release gastrin?
G cells of the antrum
Which cells release histamine?
ECL cells and mast cells of gastric wall.
What endocrine factor inhibits acid production and where does it come from?
Secretin from the small intestine.
What paracrine factor inhibits acid production?
Somatostatin
