Gastrointestinal Flashcards
Name the four quadrants of the abdomen
- Right upper quadrant 2. Left upper quadrant 3. Right lower quadrant 4. Left lower quadrant
What is the name of the vertical imaginary line splitting the quadrants of the abdomen?
The median line
What is the name of the horizontal imaginary line that splits the quadrants of the abdomen?
The transumbilical line
Name the nine regions of the abdomen
Top row from right to left- right hypchondriac, epigastric, left hypochondriac Middle from right to left- right lateral, umbilical, left lateral Bottom from right to left- right inguinal, pubic, left inguinal
Name the imaginary vertical lines splitting the nine regions of the abdomen
The right and left midclavicular lines
Name the imaginary horizontal lines splitting the nine regions of the abdomen
The subcostal and trans-tubercular lines
What is the action of the external oblique muscle?
Compressed and supports the abdominal viscera, also flexes and rotated trunk
What is the action of the internal oblique muscle?
Compressed and supports the abdominal viscera, also flexes and rotated trunk
What is the action of the transversus abdominis muscle?
Compresses and shortens the abdominal viscera
What is the action of the rectus abdominis muscle?
Flexes trunk, compresses and shortens abdominal viscera, also stabilises and controls the tilt of the pelvis
What is the innervation of the external oblique and rectus abdominis muscles?
The thoraco-abdominal and sub-costal nerves
What is the innervation of the internal oblique and transversus abdominis muscles?
The thoraco-abdominal, subcostal and first lumbar nerves
What name is given to the group of aponeuroses that closes the rectus abdominis?
The rectus sheath
The aponeuroses of which muscles make up the rectus sheath?
The external oblique, the internal oblique and the transversus abdominis
How does the rectus sheath differ above and below the umbilicus?
Above the umbilicus- aponeurosis posterior to rectus abdominis Below the umbilicus- aponeurosis anterior to rectus abdominis
Which thoracic spinal segments innervate the anterior abdominal wall?
The ventral rami of T7-T12
During what developmental process is the inguinal canal formed?
During relocation of the gonads
What are the two bony attachments of the inguinal canal?
The anterior iliac spins and the pubic tubercle of the hip bone
What makes up the anterior wall of the inguinal canal?
The aponeurosis of external oblique
What makes up the posterior wall of the inguinal canal
The transversus fascia
What forms the roof of the inguinal canal?
The rectus sheath
What forms the floor of the inguinal canal?
The inguinal ligament
What is the name of the two openings of the inguinal canal?
The deep and superficial inguinal rings
What is the relationship of the deep inguinal ring to the inferior epigastric vessels?
The ring lies lateral to the vessels
Where does the superficial inguinal ring lie in relation to the pubic tubercle?
It lies superolaterally
What are the contents of the inguinal canal in males?
The spermatic cord, vessels and the ilio-inguinal nerve
What is the contents of the inguinal canal in females?
The ligament of the uterus, vessels and the ilio-inguinal canal
What are the four layers of the gastrointestinal tract lining?
The mucosa, submucosa, muscularis propria and the serosa/adventitia
What are the three layers of the mucosa of the GI tract lining?
The epithelium, the lamina propria and the muscularis mucosae
When is the outermost layer of the GI tract lining serosa and when is it adventitia?
Inside the peritoneum- serosa Outside the peritoneum- adventitia
What is the peritoneum?
A transparent serous membrane that covers the abdominal wall and organs
What are the two subdivisions of the peritoneum and what does each cover?
The parietal peritoneum covers the abdominal wall and the visceral peritoneum covers the abdominal organs
What is the peritoneal cavity?
A potential space between the two layers of the peritoneum
What are the two major divisions of the peritoneal cavity?
The lesser sac/lesser omentum and the greater sac/greater omentum
Which of the omenta lies anterior to the stomach and which of the omenta lies posterior to the stomach?
The greater omentum lies anterior to the stomach while the lesser omentum lies posterior to the stomach
What is the name of the passage between the two omentum?
The omental or epiploic foramen
What is meant by the term “retroperitoneal”?
An organ that is only covered with peritoneum on their anterior surface, and so firmly attached to the posterior wall
What is meant by the term “intraperitoneal”?
An organ that is completely surrounded in visceral peritoneum
Through what means are intraperitoneal organs attached to the posterior wall?
Through a mesentery
What is present in the peritoneal cavity?
A small amount of fluid
Which layer of the peritoneum is more sensitive to pressure, pain and temperature?
The parietal peritoneum
What are the attachments of the greater omentum?
The greater curvature of the stomach and the transverse colon
What are the attachments of the lesser omentum?
The liver and the lesser curvature of the stomach
What is the innervation of the parietal peritoneum?
T6-L1
What is the innervation of the visceral peritoneum?
Autonomic nerves
What muscles make up the posterior abdominal wall muscles?
Psoas major, iliacus and quadratus lumborum
What are the main vessels of the posterior wall of the abdomen?
The abdominal aorta and the inferior vena cava
What are the nerves in the posterior wall of the abdomen?
The subcostal and lumbar spinal nerves
What organs are present in the posterior wall of the abdomen?
The kidneys, duodenum and colon
What are the three major hiatuses in the diaphragm and at what vertebral level does each occur?
Caval opening (IVC)- T8 Oesophageal hiatus- T10 Aortic hiatus- T12
What are the three main branches of the abdominal aorta that supply the gut tube?
The celiac, inferior mesenteric and superior mesenteric arteries
At what vertebral level does the abdominal aorta divide into two common iliac arteries?
L4
How is the IVC formed in the abdomen?
It passes through the thoracic diaphragm
Which artery supplies the foregut?
The celiac artery
Which artery supplies the midgut?
The superior mesenteric artery
Which artery supplies the hindgut?
The inferior mesenteric artery
What are the three main branches of the celiac artery?
The left gastric, hepatic and splenic arteries
What are the main branches of the superior mesenteric artery?
The ileocolic, right colic and middle colic arteries
What are the main branches of the inferior mesenteric artery?
The left colic, superior rectal and sigmoid arteries
At what vertebral level do the celiac artery, SMA and IMA branch off the aorta?
Celiac artery- T12 Superior mesenteric artery- L1 Inferior mesenteric artery- L3
Through what system does blood drain from the abdominal GI tract drain to the liver?
The hepatic portal venous system
Which two veins unite to form the portal vein?
The inferior mesenteric vein and the superior mesenteric vein
What are the four sites of portocaval anastamoses?
The distal oesophagus
The anorectal junction
The paraumbilical region
The colic veins
What is the sympathetic innervation of the abdominal viscera?
The abdominopelvic splanchnic nerves, the prevertebral sympathetic ganglia and the abdominal aortic plexus
What is the parasympathetic innervation of the abdominal viscera?
The anterior and posterior vagal trunks and the pelvic splanchnic nerves
What is the effect of the parasympathetic nervous system on GI secretion, motility and blood vessels?
It stimulates GI secretion and motility and causes vasodilation of the blood vessels
What is the effect of the sympathetic nervous system on GI secretion, motility and blood vessels?
It inhibits GI secretion and motility and causes vasoconstriction
At what vertebral levels do the kidneys lie?
T12-L3
What vessels entering into the kidneys and which lies most anterior?
Renal artery, renal vein and ureter. Renal vein lies anterior to artery and ureter runs inferiorly to both
Where is the adrenal gland located?
On the superiomedial aspect of the kidney
What is the renal pelvis?
The expanded upper part of the ureter
Where are the three constrictions of the ureter?
At the pelviureteric junction, across the brim of the pelvic inlet and through the wall of the urinary bladder
Where does the liver lie in relation to the ribs?
Deep to ribs 7-11
What are the three constrictions of the oesophagus?
The cervical, thoracic and diaphragmatic constrictions
What structures traverse the oesophageal opening?
The oesophagus, vagal trunks, oesophageal branches of the left gastric vessels and the lymphatic vessels
What is the blood supply and venous & lymphatic drainage of the abdominal part of the oesophagus?
Blood supply- branches of left gastric artery Venous drainage- left gastric vein Lymphatic drainage- Preaortic and coeliac nodes
What are the two orifices/openings of the stomach?
The cardial orifice and the pyloric orifice
What are the names of the two curvatures of the stomach?
The greater curvature and the lesser curvature
What are the two surfaces of the stomach?
The anterior surface and the posterior surface
What are the four main parts of the stomach?
The fundus, body, pylorus and the cardial part
What is the pyloric sphincter?
A band of circular smooth muscle at the junction of the stomach and the duodenum
What is the function of the pyloric sphincter?
To control gastric emptying
The pyloric sphincter is formed from the thickening of which layer of the gut tube?
The circular layer of the muscularis externa
What are the gastric rugae formed from?
The gastric mucosa
In which portions of the stomach are the rugae most apparent?
The pyloric part and the greater curve
What are the primary groups of lymph nodes in the stomach?
Gastric lymph nodes Pancreaticosplenic lymph nodes Gastro-omental lymph nodes Pyloric lymph nodes Pancreatico-duodenal lymph nodes
Which group of lymph nodes do the primary groups of lymph nodes of the stomach drain in to?
The celiac lymph nodes
What effect does increased vagal activity have on the pylorus and gastric secretion?
Increased vagal activity increases both pyloric activity and gastric secretion
What are the three parts of the small intestine?
The duodenum, jejunum and the ileum
Which part of the small intestine does the bile duct open into?
The second part of the duodenum
Where is the boundary between the foregut and the midgut?
At the distal end of the duodenum
How are the different parts of the small intestine peritonised?
Duodenum- first 2cm intraperitoneal, rest retroperitoneal Jejunum- intraperitoneal Ileum- intraperitoneal
Which part of the small intestine is the shortest?
The duodenum
Are the arterial loops of the small intestine more present in the jeunum or the ileum?
In the ileum
What features are present in the large intestine that aren’t present in the small intestine?
The tenicae coli, haustra and omental appendices
How are the different parts of the large intestine peritonised?
Caecum- intraperitoneal Ascedning colon- retroperitoneal Transverse colon- intraperitoneal Descending colon- retroperitoneal Sigmoid colon- intraperitoneal
Where is the boundary between the midgut and the hindgut?
About two thirds of the way down the transverse colon
What structures open into the cavity of the caecum?
The ileum and the appendix
What is McBurney’s point?
The lowest point of the appendix, also site of most acute inflammation in appendicitis
On which omentum are the hepatoduodenal and hepatogastric ligaments?
The lesser omentum
What connects the liver to the anterior abdominal wall?
The falciform ligament
How many layers of peritoneum are present in the greater omentum?
Four
What are the paracolic gutters?
They are grooves used for free communication
Where are the paracolic gutters found in relation to the colon?
They are found between the lateral aspect of the ascending/descending colon and the posterior wall
What type of muscle is the muscularis externa in the oesophagus?
Smooth
What kind of epithelium is present in the mucosa of the oesophagus?
Stratified squamous non-keratinising epithelium
What type of muscle is the muscularis mucosae in the oesophagus?
Smooth
What kind of epithelium is present in the mucosa of the small intestine?
Simple columnar
What type of muscle is the muscularis mucosae in the small intestine?
Smooth
Where in the gut tube do glands extend beyond the muscularis mucosae?
The oesophagus and the duodenum
Where is the transpyloric plane?
Halfway between the jugular notch and the pubic symphisis
How is the spleen peritonised?
Intraperitoneal
In which region of the abdomen is the spleen located?
The left hypochondriac
What structures are present in the hilum of the spleen?
The gastrosplenic ligament, the splenic artery and the splenic vein
The tail of which organ lies close to the hilum of the spleen?
The pancreas
What are the main functions of the spleen?
Storage of red blood cells
Storage of platelets
Filtering blood
Phagocytosis
What are the main parts of the pancreas?
The head, neck, body, tail and the ucinate process
How is the pancreas related to the duodenum?
The head of the pancreas lies in the curve of the duodenum
Where is the inferior mesenteric artery formed?
Posterior to the neck of the pancreas
Into which part of the duodenum does the pancreatic duct open?
The minor duodenal papilla
What are the two main lobes of the liver, visible anteriorly?
The right and left lobes
What are the two, smaller lobes of the liver that are only visible posteriorly?
The caudate lobe (superior) and the quadrate lobe (inferior)
What structures are present in the porta hepatis?
Hepatic portal vein Hepatic artery Hepatic nerve plexus Hepatic duct Lymphatic vessels
Which fold of the omentum is wrapped around the porta hepatis?
The lesser omentum
What does the extrahepatic biliary apparatus consist of?
Cystic duct
Common hepatic ducts
Gall bladder
Liver
Bile duct
Where is bile produced?
In the liver
Where is bile stored and concentrated?
In the gallbladder
Where does bile enter into the gut tube?
In the duodenum
What vessels form Calot’s cystohepatic triangle?
The cystic duct, common hepatic duct and the inferior surface of the liver
What is the main content of white and red pulp in the spleen?
White pulp- lymphatic tissue of white blood cells Red pulp- venous sinuses and splenic cords
Which costal cartilage is the surface marking of the gallbladder?
Ninth
Which ribs are related to the spleen?
9-11
Which abdominal plane crosses the pancreas and what part of the pancreas does it cross?
The transpyloric plane, crossing the neck of the pancreas
