Stomach, duodenum and coeliac vessels Flashcards
What are the features of the stomach?
- Lies in the left upper quadrant of the abdomen.
- Dilated part of the gut tube
- Breaks down food mechanically (has additional oblique muscle layer) and chemically.
- Has 4 regions: Cardia, fundus, body & pyloric (antrum & canal).
- 2 openings (cardia and pylorus), 2 curvatures, 2 omenta, 2 groups of ligaments, 2 surfaces, 2 nerves.
Discuss Food entry and exit in the stomach.
- Food entry via the cardia (T10)
- Food exits via the pyloric sphincter (L1)
*VERY strong sphincter here!
Discuss absorption in the stomach.
- Very little absorption.
- Only a few highly lipid-soluble substances such as alcohol and some drugs are absorbed.
What happens to food in the stomach?
- Food churned into liquid chyme.
- May remain here for up to 4 hours.
- Released via pylorus intermittently into the duodenum via sphincter (thickening of inner circular layer of muscle).
List the muscles that make up the stomach.
- Longitudinal smooth muscle (outer)
- Circular smooth muscle
- Oblique smooth muscle (innermost)
What lines the stomach?
- Columnar epithelium
- Contains folds – rugae which increase surface area
- Glands / secretion – see HoL
What are the 2 omenta that attach to the stomach?
- Lesser omentum: double layer of peritoneum that extends from the liver to the lesser curvature of the stomach the first part of the duodenum.
- Greater omentum: extends from the greater curvature of the stomach to the transverse colon.
What are the ligaments of the stomach?
- Ligaments attached to the lesser curvature:
1. Gastrohepatic.
2. Hepatoduodenal. - Ligaments attached to the greater curvature:
1. Gastrophrenic.
2. Gastrosplenic.
3. Gastrocolic.
What are the anterior surface relations surfaces of the stomach?
Anterior surface relations:
- Abdominal wall, costal margin, diaphragm, left lobe of liver.
- Ulcer may cause a perforation.
What are the posterior surface relations surfaces of the stomach?
Posterior surface relations:
- Lesser sac.
- Pancreas, splenic artery, spleen, left kidney & adrenal; transverse mesocolon.
- Spleen.
- Ulcer may cause a lesser sac abscess, or erode into the pancreas or splenic artery.
What is the epiploic foramen of winslow?
- Opening into the lesser sac.
- Contents:
1. Anterior – vein: Portal vein
2. Posterior – vein: Inferior vena cava
3. Superior – liver: Caudate lobe
4. Inferior – duodenum: Duodenum (D1)
What is the blood supply of the Foregut?
- Lower oesophagus to Duodenum /D2
- Coeliac trunk - Aorta T12
What is the branches of the coeliac trunk?
- At level T12.
- 3 branches:
1. left gastric: supplies upper Lesser Curvature
2. Common hepatic:
*Right gastric – lower LC
*Gastroduodenal: Right Gastro-epiploic (lower GC) and Superior pancreaticoduodenal artery
3. Splenic:
*Runs along pancreas to spleen
*Short gastric arteries – fundus
*Left gastro-epiploic – upper GC
What is the venous drainage of the stomach?
- Lesser curve into Portal vein
- Greater curve into splenic & SMV (superior. mesenteric vein).
- Left gastric vein – lower oesophagus.
What is portal hypertension?
- Elevated pressure in your portal venous system.
- Can cause oesophageal varices – swollen, tortuous (+/- bleeding!) submucosal veins
What is lymphatic drainage of the stomach?
- Run back along the arteries to Coeliac nodes
*Perigastric
*Supra-pancreatic & along great vessels *Retropancreatic & para-aortic
What is Troisier’s sign (Virchow’s node)?
- Finding a palpable left supraclavicular lymph node.
- It may indicate GI malignancy, commonly of the stomach, or less commonly, lung cancer.
What is the nervous supply of the stomach?
- Autonomic nervous system – coeliac plexus
1. Lies at T12 – L1
2. Multiple secondary plexuses - Sympathetics: Coeliac ganglia
1. Three thoracic splanchnic nerves. - Parasympathetics: Vagal trunks
1. Anterior & posterior vagal trunks: Nerves of Latarjet
2. Run along lesser curvature
3. Used to be divided in ulcer operations.
What are the features of the spleen?
- Left hypochondrium
- Lies deep to ribs 9 – 11
- Splenomegaly: only palpable if x3 normal size
What is the function of the spleen?
- Filters blood: foreign antigens, old erythrocytes
- Extremely vascular!!: Trauma +++ bleeding due to Splenic artery (coeliac trunk).
What are the surface relations of the spleen?
GRIP:
- Gastric
- Renal
- Intestinal
- Pancreatic
What is the blood supply of the spleen?
- Splenic artery, runs with tail of pancreas in splenorenal ligament.
- The gastrosplenic ligament carries short gastrics and left gastro-epiploic arteries to stomach.
What is the venous drainage of the spleen?
- Superior Mesenteric & splenic veins joint at L1 – behind neck of pancreas to form the Portal vein (Inferior Mesenteric runs into splenic).
What is another name for the splenorenal ligament?
- Lienorenal ligament
What are the divisions of the duodenum?
10 inches (25cm) long
- D1 – 2 inches long, at L1
- D2 – 3 inches long, at L2
- D3 – 4 inches long, at L3
- D4 – 1 inch long, at L2
What is there to note about the D1 division?
- 2 inches or 5cm long
- 1⁄2 - mobile, between greater & lesser omenta
1. Duodenal cap – smooth wall
2. Common site of PUD
3. 3cm retroperitoneal
What are the posterior relations of the D1 division?
- May be damaged by a penetrating (posterior wall) ulcer.
- Gastroduodenal artery (branch of hepatic).
- Common bile duct.
- Portal vein.
What is there to note about the D2 division?
- 3 inches long.
- Major papilla - watershed of foregut & midgut. Point where the dilated junction of the pancreatic duct and the bile duct (ampulla of Vater) enter the duodenum.
- Contains Plicae circulares (valvulae conniventes)= folds.
What are the D2 relations?
- Posteriorly: Right kidney & ureter.
- Anteriorly: Transverse mesentery.
What are the features of D3 and what are its relations?
- 4 inches long: runs transversely @ L3.
- Posteriorly: Aorta & IVC.
- Anteriorly: SMA & SMV, Root of the mesentery.
What are the features of D4?
- Shortest part – 1 inch
- Duodeno-jejunal (DJ) flexure
*Ligament of Treitz- supports and anchors the duodenum.
What is the duodenal cap?
- The very first part of the duodenum which is slightly dilated.
- It’s intraperitoneal.
- It is mobile and has a mesentery.
- It is also smooth walled.
- Supplied by Hepatic, gastroduodenal, right gastric and right gastro-epiploic (omental).
What is the arterial supply of the foregut?
- Common hepatic →
- Gastroduodenal artery →
- Superior pancreaticoduodenal artery:
*Anterior & posterior branches
What is the arterial supply of the midgut?
- Superior mesenteric artery
*Inferior pancreaticoduodenal artery
*Anterior & posterior branches
What is the venous drainage of duodenum?
- Veins mostly correspond:
1. Except – gastroduodenal vein absent
2. Pre-pyloric vein of mayo usually present
