Class 3 - Station 1: Gut Tube part 1 - Oesophagus & Stomach Flashcards
What is the oesophagus?
- Muscular tube
How long is the oesophagus and what does it extend between?
- 25cm
- Pharynx to stomach
What are the 3 oesophageal constrictions?
Cervical
Thoracic
Diaphragmatic
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What vertebral level is the oesophageal hiatus of the diaphragm?
T10
What nerve passes through the oesophageal opening?
Vagus
- Anterior and posterior trunk
What lymph vessels pass through the oesophageal hiatus?
Paraoesophageal lymph vessels
What is the arterial supply and venous drainage of the UPPER 1/3rd of the oesophagus?
- Inferior thyroid artery
- Inferior thyroid vein
What is the arterial supply and venous drainage of the MIDDLE 1/3rd of the oesophagus?
- Abdominal aorta
- Azygous vein
What is the arterial supply and venous drainage of the ABDOMINAL oesophagus?
- Left gastric artery
- Left gastric vein
ARTERIAL SUPPLY
VENOUS DRAINAGE (the coronary vein is AKA the left gastric)
What is the lymphatic drainage of the upper 1/3rd, middle 1/3rd and abdominal oesophagus?
Upper - Deep cervical
Middle - Mediastinal
Abdominal - Coeliac lymph nodes
What is the most common cause of haematemesis?
Ruptured oesophageal varices from the portocaval anastomosis i.e. PORTAL HYPERTENSION
A. Identify this structure.
B. Name this area of the stomach.
C. Name this area of the stomach.
D. What are these folds in the mucosa called.
E. Name the area.
F. Name this ring of smooth muscle
G. Identify this
H. Name this area
I. Name this area of the stomach.
J. Name this area.
A. Oesophagus
B. Cardia
C. Fundus
D. Rugae
E. Lesser curvature
F. Pyloric sphincter
G. 1st Part of duodenum
H. Body
I. Pylorus
J. Greater curvature
What is the pyloric sphincter?
A ring of smooth muscle that increases mixing of stomach contents and allows food to enter the GI tract
What layer of the gut tube forms the pyloric sphincter and how does it do it?
Muscularis externa
- Thickens at this area
What is congenital pyloric stenosis?
A birth defect caused by thickening of the pyloric muscle.
- Projectile vomiting regularly
- Leads to malnutrition
What two organs is the stomach suspended between?
- Liver
- Transerse colon
What two structures does the lesser omentum extend from?
Liver and lesser curvature
What does the greater omentum extend from?
Greater curvature to the transverse colon
How are rugae formed?
Mucosal layer folding over to allow expansion (similar to an accordian).
In which portions of the stomach are rugae most apparent?
Greater curvature
Pyloric area
Stomach bed
Dr
Satan
Sen
Kills
Patients
Cruelly
and
Mercilessly
Dr - Diaphragm (left crus)
Satan - Splenic artery
Sen - left suprarenal gland
Kills - left kidney
Patients - pancreas
Cruelly - left colic flexure (splenic)
Mercillesly - mesocolon (transverse)
Label
- Probe through epiploic foramen
- Gall bladder
- Hepatic flexure
- Duodenum
- Greater omentum
- Pancreas
- Transverse mesocolon
- Transverse colon
- Splenic flexure
- Spleen
- Stomach
What are the three muscular layers of the stomach?
- Longitudinal
- Circular
- Oblique
- Splenic Artery
- Left Gastric
- Coeliac trunk
- Left hepatic artery
- Right hepatic artery
- Cystic artery
- Common hepatic artery
- Right gastric artery
- Gastroduodenal artery
- Pancreaticoduodenal artery
- Right gastroepiploic artery
- Hepatic artery
- Left gastroepiploic artery
- Short gastric arteries
How is the stomach drained of blood?
Hepatic portal system
What are the 4 major groups of lymph nodes that drain the stomach?
- Superior gastric
- Supra pyloric
- Pacreaticolineal
- Inferior gastric
What group of lymph nodes does the superior gastric, supraplyoric, pancreaticolineal and inferior gastric nodes eventually drain into?
Coeliac lymph nodes
Where in the stomach is gastric cancer most common?
The greater curvature
What nerve is the most important in controlling gastric motility?
The vagus nerve (CrN X)
What is the effect of increased vagal tone on the pyloric sphincter?
Causes it to relax
What is the effect of increased vagal tone on gastric secretion?
Increases
What can a vagotomy be used to treat?
- Due to the arrangement of vagal branches surgeons can bee highly selective.
- Areas of the stomach that over produce gastric acid can be denervated but the pyloric antrum can remain innervated to ensure gastric motility is unnaffected.
