stomach and spleen Flashcards
What 5 structures are included in the foregut?
including the stomach, pancreas, spleen, liver, and gallbladder.
where is the foregut
Distal esophagus to superior half of the duodenum
What is the arterial supply for the foregut?
Coeliac trunk
where is the midgut
Inferior half of the duodenum to proximal 2/3 of the transverse colon
What 5 structures are included in the midgut?
including the jejunum, ileum, caecum, appendix, and ascending colon.
What is the arterial supply for the midgut?
Superior mesenteric artery
where is the hindgut
Distal 1/3 of the transverse colon to the superior half of the rectum
What 2 structures are included in the hindgut?
including the descending colon and sigmoid colon.
What is the arterial supply for the hindgut?
Inferior mesenteric artery
What is the peritoneal status of the stomach?
The stomach is intraperitoneal.
Where is the stomach commonly located in the supine position?
Left upper quadrant (LUQ)
Pylorus: Right upper quadrant (RUQ)
Also found in: Epigastric, umbilical, and left hypochondrium regions
What 4 factors can cause variations in the stomach’s size, shape, and position?
Body type of the person
Diaphragmatic movements
Stomach content
Position of the person
Why is the transpyloric plane an important anatomical landmark?
The pylorus hardly moves because it is connected to the duodenum, which is mostly retroperitoneal.
Where is the spleen located?
Left upper quadrant (LUQ) or the left hypochondrium region.
What protects the spleen?
The thoracic cage, making it well protected.
What ribs is the spleen associated with posteriorly?
Left 9th to 11th ribs.
How is the spleen’s long axis oriented when viewed laterally?
Roughly parallel to the left 10th rib.
What is the function of the stomach?
The stomach accumulates ingested food, chemically and mechanically prepares it for digestion, and helps turn food into chyme.
What are the four parts of the stomach?
Cardia
Fundus
Body
Pyloric part
What are the key features of the cardia?
Surrounds the cardial orifice (superior opening of the stomach).
Located in the epigastric region.
Lies posterior to the 6th left costal cartilage at T11.
What is the fundus of the stomach?
The dilated part superior to an imaginary transverse line at the level of the cardial orifice.
What is the body of the stomach?
The major part of the stomach.
What are the key features of the pyloric part?
Outflow region of the stomach.
Includes the pyloric antrum, pyloric canal, and pylorus.
The pylorus is a distal sphincter (smooth muscle) that controls stomach content discharge into the duodenum.
What protects the internal surface of the stomach?
A continuous mucous layer, which shields it from gastric acid secreted by gastric glands
What are the gastric folds (rugae) and their function?
Prominent folds in the gastric mucosa.
Increase surface area for digestion and absorption.
What happens to the gastric folds (rugae) when the stomach fills?
They diminish as the stomach expands.
How is the omentum related to the stomach?
The lesser omentum extends around the stomach.
Continues as the greater omentum at the greater curvature.
What structures are related to the stomach anteriorly?
Left lobe of the liver
Anterior abdominal wall
What structures are related to the stomach posteriorly?
Omental bursa
Pancreas
What structure is related to the stomach inferiorly?
Transverse colon
What type of organ is the spleen anatomically and functionally?
Anatomically: An abdominal organ.
Functionally: A lymphatic organ.
What is the immune function of the spleen?
It acts as a site for lymphocyte proliferation and immune surveillance and response.
What is the haematopoietic function of the spleen prenatally, and after birth?
Prenatally: Functions as a blood-forming (haematopoietic) organ.
After birth: Removes and destroys aging red blood cells & platelets while storing newly generated ones.
What are the key characteristics of the spleen’s borders?
Anterior & superior borders: Sharp and often notched.
Posterior & inferior borders: Rounded.
What are the 3 main surfaces and areas of the spleen?
- Costal surface
- Visceral surface
- Gastric area (contacts the stomach)
- Renal area (contacts the left kidney)
- Colic area (contacts the colon) - Hilum (contains the splenic artery & vein)
What 2 ligaments connect the spleen to surrounding structures?
Gastrosplenic ligament (connects spleen to greater curvature of stomach).
Splenorenal ligament (connects spleen to left kidney).
What 2 things is attached to the hilum of the spleen?
The splenic vessels and the tail of the pancreas.
What structure is related to the spleen anteromedially?
Stomach
What 3 structures are related to the spleen posterolaterally?
Left diaphragm.
Left ribs 9-11.
Hilum is at the level of rib 10.
What structure is related to the spleen inferiorly?
Left colic flexure (junction between transverse and descending colon).
What structure is related to the spleen posteromedially?
Left kidney.
What organs does the coeliac trunk supply?
The stomach and spleen, as they are part of the foregut.
At what vertebral level is the coeliac trunk located?
T12 (at the level of the aortic hiatus).
How long is the coeliac trunk?
Very short, approximately 1 cm long.
What are the three main branches of the coeliac trunk?
Left gastric artery
Splenic artery
Common hepatic artery
What are the 2 main arterial anastomoses supplying the stomach?
Lesser curvature: Right and left gastric arteries.
Greater curvature: Right and left gastro-omental (gastroepiploic) arteries.
What 2 arteries supply the fundus and upper body of the stomach?
Short gastric arteries (branches of the splenic artery).
Posterior gastric arteries (branches of the splenic artery).
What is unique about the arterial supply of the stomach?
The stomach is the only foregut structure that receives blood from all three branches of the coeliac trunk.
What are the main arterial branches supplying the stomach?
Left gastric artery – Direct branch of the coeliac trunk.
Right gastric artery – Branch of the common hepatic artery.
Right gastro-omental artery – Branch of the gastroduodenal artery, which is a branch of the common hepatic artery.
Short gastric & posterior gastric arteries – Branches of the splenic artery.
How do the veins of the stomach run in relation to the arteries?
They run parallel to the arteries in position and course.
What are the two main drainage pathways for venous blood from the stomach?
Direct drainage into the hepatic portal vein.
Via the splenic, superior, or inferior mesenteric veins, which then drain into the hepatic portal vein.
What are the 6 main veins draining the stomach?
Left gastric vein
Right gastric vein
Short gastric veins
Splenic vein
Left gastro-omental vein
Right gastro-omental vein
What is the main venous structure that ultimately collects blood from the stomach?
The hepatic portal vein.
Which 2 veins drain directly into the hepatic portal vein?
Right gastric vein
Left gastric vein
Where do the short gastric veins and left gastro-omental vein drain
They drain into the splenic vein, which joins the superior mesenteric vein (SMV) to form the hepatic portal vein.
Where does the right gastro-omental vein drain?
It empties into the superior mesenteric vein (SMV)
What is the arterial supply of the spleen?
Splenic artery, a branch of the coeliac trunk.
What is the course of the splenic artery?
It follows a tortuous path along the superior border of the pancreas.
What is the venous drainage of the spleen?
Splenic vein, which drains into the hepatic portal vein.
What 2 veins join the splenic vein?
Inferior mesenteric vein (IMV).
Runs posterior to the body and tail of the pancreas.
What is the parasympathetic nerve supply of the stomach?
Anterior & posterior vagal trunks and their branches.
Enter the abdomen through the oesophageal hiatus.
What is the sympathetic nerve supply of the stomach?
Preganglionic sympathetic fibers from T5-T9/10 spinal cord segments.
Travel via the greater splanchnic nerve to the coeliac ganglion.
Synapse in the coeliac ganglion, becoming postganglionic fibers that continue to the stomach.
what is the sympathetic nerve supply of the spleen?
Same as the stomach—from the coeliac ganglion via postganglionic fibers.
What is the parasympathetic nerve supply of the spleen?
From the vagal trunks.
How do the sympathetic and parasympathetic fibers reach the spleen?
They travel along the splenic artery as the splenic nerves.
Why is a ruptured spleen dangerous?
The spleen acts as a blood reservoir, so rupture causes profuse bleeding (intraperitoneal hemorrhage).
How can blunt trauma lead to spleen rupture?
The spleen is well protected by ribs.
Trauma to the left side of the abdomen can fracture ribs and rupture the spleen.
Why is the spleen normally not palpable?
It is protected by the ribcage, making it difficult to feel under normal conditions.
What is splenomegaly, and how can it be detected?
Splenomegaly = enlarged spleen, often due to hematopoietic disorders.
The inferior edge of the spleen can be palpated below the left costal margin at the end of inspiration (when pushed down by the diaphragm).
What anatomical changes occur in severe splenomegaly?
Left colic (splenic) flexure and transverse colon are displaced inferiorly.
The descending colon shifts medially.
