Gastrointestinal System Flashcards
What are the four quadrants of the abdomen?
Right upper quadrant
Left upper quadrant
Right lower quadrant
Left lower quadrant
What is the horizontal plane which separates the quadrants of the abdomen?
Median plane
What is the vertical plane which separates the quadrants of the abdomen?
Transumbillical plane
What are the six regions of the abdomen?
Right hypochondriac
Epigastric
Left hypochondriac
Right lumbar
Umbillical
Left lumbar
Right lingual
Pubic hypogastric
Left lingual
What are the abdominal regions divided vertically by?
Mid-clavicular lines
What are the abdominal regions divided horizontally by?
Subcostal plane
Transtubercular plane
What organ is found in the right hypochondriac region?
Liver
What organ is found in the epigastric region?
Stomach
What organ is found in the left hypochondriac region?
Spleen
What organ is found in the right lumbar region?
Gallbladder
Liver
Ascending colon
What organ is found in the umbilical region?
Small bowel
What organ is found in the left lumbar region?
Descending colon
Left Kidney
What organ is found in the right lingual region?
Caecum
Appendix
What organ is found in the hypogastric region?
Urinary bladder
Reproductive organs
What organ is found in the left lingual region?
Descending colon
Sigmoid colon
What are dermatomes?
The area of skin supplied by a single spinal nerve
What dermatome is the umbilicus in?
T10
What is the vertebral level of the umbilicus?
L3-L4
What is the orientation of external oblique fibres?
Infermoedial
What are the two functions of external oblique fibres?
To compress and support viscera
To flex and rotate the trunk
What range of nerves innervate the external oblique fibres?
T7-T12
What is the orientation of internal oblique fibres?
Inferomedial perpendicular to the external oblique fibres
What are the two functions of internal oblique fibres?
To compress and support viscera
To flex and rotate the trunk
What range of nerves innervate the internal oblique fibres?
T7-T11
L1
What is the orientation of transversus abdominis fibres?
Horizontal
What is the function of transversus abdominis fibres?
To compress and support viscera
What range of nerves innervate the transversus abdominis fibres?
T7-T11
L1
What is the orientation of rectus abdominis fibres?
Vertical
What are the three functions of the rectus abdominis fibres?
To flex the trunk
To compress viscera
To stabilise the pelvis
What range of nerves innervate the rectus abdominis fibres?
T7-T12
How can we remember the direction of the external oblique fibres?
The external oblique muscle runs in the direction as if you were putting your hands in your jacket pockets
The rectus sheath is formed from the aponeurosis of what three muscles?
Transversus abdominis
Internal oblique
External oblique
What two muscles lie within the rectus sheath?
Rectus abdominis
Pyramidalis
What is the horizontal line of connective tissue situated in the centre of the rectus sheath?
Linea alba
What is the function of the pyramidalis?
To tense the linea alba
Where does the rectus sheath end?
Arcuate line
What abdominal muscle is outermost?
External oblique
What abdominal muscle is found in the second outermost layer of the abdomen?
Internal oblique
What abdominal muscle is found in the third outermost layer of the abdomen?
Rectus abdominis
What abdominal muscle is found in the innermost layer of the abdomen?
Transversus abdominis
What is the final layer before the abdominal cavity?
Parietal peritoneum
What are the four superficial blood vessels which supply the abdominal wall?
Superior epigastric artery
Superior epigastric vein
Inferior epigastric artery
Inferior epigastric vein
What is the superior epigastric artery a branch of?
Internal thoracic artery
What is the inferior epigastric artery a branch of?
External iliac artery
What is the superior epigastric vein a branch of?
Internal thoracic vein
What is the inferior epigastric vein a branch of?
External iliac vein
What is caput medusa?
Dilatation of the abdominal veins which extend from the umbilicus
Where does lymph from above the umbilicus drain to?
Axillary lymph nodes
Where does lymph from below the umbilicus drain to?
Superficial inguinal lymph nodes
What is the role of the inguinal canal?
To allow structures from the abdomen to pass to the genital region
Where does the inguinal ligament originate?
The anterior superior iliac spine
Where does the inguinal ligament end?
The pubic tubercle
What is the inguinal ligament formed from?
Aponeurosis of the external oblique muscle
What is the superficial inguinal ring?
A break in the aponeurosis of the external oblique layer
Where is the superficial inguinal ring situated in relation to the pubic tubercle?
Superolateral
Where is the deep inguinal ring situated in relation to the pubic tubercle?
Superolateral
What is the deep inguinal ring?
An oval shaped opening in the transversalis muscle fascia
What are the three contents of the inguinal canal in males?
Spermatic cord
Ilioguinal nerve
Blood and lymphatics
What are the three contents of the inguinal canal in females?
Round ligament
Genitofemoral nerve
Blood and lymphatics
What are the three layers of the spermatic cord?
Internal spermatic fascia
Cremasteric fascia
External spermatic fascia
In what layer of the abdominal wall is the internal spermatic fascia of the spermatic cord found?
Transversus abdominis
In what layer of the abdominal wall is the cremasteric fascia of the spermatic cord found?
Internal oblique
In what layer of the abdominal wall is the external spermatic fascia of the spermatic cord found?
External oblique
What are the three muscles of the posterior abdominal wall?
Psoas major
Iliacus
Quadratus lumborum
What are the two functions of the psoas major?
To flex the trunk and thigh
To balance the trunk
What are the two functions of the iliacus?
To flex the thigh
To stabilise hip joints
What are the two functions of the quadratus lumborum?
To flex the vertebral column
To fix the 12th rib for inspiration
At what vertebral level does the caval opening occur?
T8
At what vertebral level does the eosophageal hiatus occur?
T10
At what vertebral level does the aortic hiatus occur?
T12
What structure passes through the caval opening?
IVC
What two vessels run in the posterior abdominal cavity?
Aorta
IVC
What posterior abdominal vessel sits most anteriorly?
IVC
Where does the foregut run from?
Oesophagus to duodenum
What four structures are included in the foregut?
Liver, gall bladder, spleen, pancreas
Where does the midgut run from?
Duodenum to the transverse colon
Where does the hindgut run from?
Transverse colon to the rectum
What are the three main vessels which supply the abdomen?
Celiac
Superior mesenteric artery
Inferior mesenteric artery
What does the celiac artery supply?
Foregut
Where does the celiac artery branch off from the abdominal aorta?
T12
What does the SMA supply?
Midgut
Where does the SMA branch off from the abdominal aorta?
L1
What does the IMA supply?
Hindgut
Where does the IMA branch off from the abdominal aorta?
L3
What are the three branches of the celiac trunk?
Left gastric artery
Spelnic artery
Common hepatic artery
What artery comes off the side of the abdominal wall at L1?
Renal artery
At what level does the abdominal wall divide into the two common iliac arteries?
L4
What are the four veins of the abdomen?
Hepatic portal vein
Left renal vein
Inferior mesenteric vein
Inferior vena cava
What two vessels merge form to form the IVC?
Right and left common iliac veins
What two veins form the hepatic portal vein?
Superior mesenteric vein
Splenic vein
What does the inferior mesenteric vein drain into?
Portal system
Systemic system
What are the four sites of the portal-systemic anastomoses?
Oesophageal
Rectal
Retroperitoneal
Paraumbilical
What is the clinical significance of portal-systemic anastomoses?
When blood flow through the portal system is obstructed, blood is re-directed through these sites, which can result in varices
What is pre-aortic drainage?
When vessels come out of the aorta anteriorly
What is para-aortic drainage?
When vessels come out of the aorta posteriorly
What three sympathetic nerves that supply the posterior abdominal wall?
Abdominopelvic splanchnic nerves - greater, lesser, least
Prevertebral sympathetic ganglia
Abdominal aortic plexuses
What two parasympathetic nerves that supply the posterior abdominal wall?
Vagus nerve
Pelvic splanchnic nerves (S2, S3, S4)
How does the parasympathetic system affect GI secretions?
Increases
How does the sympathetic system affect GI secretions?
Decreases
How does the parasympathetic system affect GI motility?
Increases
How does the sympathetic system affect GI motility?
Decreases
How does the parasympathetic system affect blood vessels in the GI tract?
Vasodilation
How does the sympathetic system affect blood vessels in the GI tract?
Vasoconstriction
How does vagotomy effect gastric secretions?
It reduces secretions
What type of pain occurs in the foregut?
Epigastric
What type of pain occurs in the midgut?
Umbillical
What type of pain occurs in the hindgut?
Suprapubic
Where does appendicitis pain usually occur?
Left iliac fossa
Where does the lumbar plexus originate from?
Ventral rami of L1-L4
Where is the lumbar plexus formed?
Psoas major
What are the six lumbar nerves which form the lumbar plexus?
Obturator nerve
Femoral nerve
Iliohypogastric nerve
Ilioinguinal nerve
Genitofemoral nerve
Lateral fermoral cutaneous nerve
What is the nerve root value of the obturator nerve?
L2-L4
What is the nerve root value of the femoral nerve?
L2-L4
What is the nerve root value of the genitofemoral nerve?
L1, L2
At what vertebral level do the kidneys lie?
T12-L3
Why is the right kidney slightly lower than the left kidney?
The presence of the liver
What three structures leave the kidney - from most superior to posterior?
Renal artery
Renal vein
Ureter
Are kidneys retroperitoneal or intraperitoneal?
Retroperitoneal
Are the ureters retroperitoneal or intraperitoneal?
Retroperitoneal
What is the term used to describe the upper part of the ureter?
Renal pelvis
Name the three constriction points of the ureter
At the junction between the ureters and renal pelvis
Where the utterers cross the brim of the pelvic inlet
During the passage through the wall of the urinary bladder
Where is the suprarenal gland located?
Between the supromedial aspects of the kidneys and diaphragmatic aura
What type of gland is the suprarenal gland?
Endocrine
What is the peritoneum?
A continuous membrane which lines the abdominal cavity and covers the abdominal organs.
What is the parietal peritoneum?
The peritoneum which lines the body wall
What is the visceral peritoneum?
The peritoneum which lines the viscera
What peritoneum is more sensitive to pressure, pain and heat?
Parietal
What is the peritoneal cavity?
A space between the parietal and visceral peritoneum
What is present within the peritoneal cavity?
Peritoneal fluid
What are intraperitoneal organs?
Organs in which the visceral peritoneum only covers the anterior surface and therefore they are firmly attached to the posterior abdominal wall
What are retroperitoneal organs?
Organs in which the visceral peritoneum covers the whole of the organ
List eight retroperitoneal organs - remembered via SAD PUCKER
Suprarenal gland
Aorta
Duodenum
Pancreas
Colon
Kidney
Oesophagus
Rectum
List seven intraperitoneal organs
Liver
Spleen
Stomach
Jejunum
Ileum
Transverse colon
Sigmoid colon
Through what structure do the lesser and greater sac communicate with one another?
Epiploic foramen
Where does the lesser sac lie?
Posterior to the stomach
Where does the greater sac lie?
It extends from the diaphragm to the pelvis
What is the greater omentum?
It attaches from the greater curvature of the stomach to the duodenum
What is the lesser omentum?
It attaches from the lesser curvature of the stomach to the liver
What nerves innervate the parietal peritoneum?
T6-T12
L1
What nerves innervate the visceral peritoneum?
Autonomic nerves
What omentum are the hepatoduodenual and hepatogastric ligaments part of?
Lesser omentum
What is the falciform ligament?
A ligament that attaches the liver to the anterior abdominal wall
What structure in the falciform ligament is a remnant of the umbilical vein?
Round ligament
What are the three abdominal viscera which lie in the mesentery?
Small intestine
Colon
Rectum
What is the transpyloric plane?
A plane halfway between the suprasternal notch of the manubrium (L1)
How do we locate the transpyloric plane?
It is halfway between the jugular notch and the border of the pubic symphysis
What costal cartilage is the surface marking of the gallbladder?
9th
Does the liver move with respiration?
Yes
Where does the spleen lie?
From ribs 9 to 11 on the left hand side
Does the spleen move with respiration?
Yes
What is the oesophagus?
An extension from the pharynx to the stomach
Where are the three constrictions of the oesophagus?
Cervical
Thoracic
Diaphragmatic
What four structures pass through the oesophageal opening of the diaphragm?
Oesophagus
Left gastric artery and vein
Left and right vagus nerve
Lymphatics
What three arteries supply the oesophagus with blood?
Left gastric artery
Celiac trunk
Left inferior phrenic artery
What vein drains the oesophagus of blood?
Left gastric vein
How is the oesophagus lymph drained?
Left gastric lymph nodes, which drain into the celiac lymph nodes
Where does the lesser omentum extend from?
Smaller curvature of the stomach to the liver
Where does the greater omentum extend from?
Greater curvature of the stomach to the posterior abdominal wall
What is the pyloric sphincter?
A band of smooth muscle between the pylorus and the duodenum
What layer of the stomach do the rugae exist?
Mucosal and submucosal
In what two areas of the stomach are the rugae most prominent?
Pylorus
Greater curvature
What are the four main veins which drain blood from the stomach?
Left gastric vein
Right gastric vein
Left gastro-omental vein
Right gastro-omental vein
Where do the gastric veins drain into?
Hepatic portal vein
Where does the left gastro-omental veins drain into?
Splenic vein then the hepatic portal vein
Where does the right gastro-omental veins drain into?
SMV then to the hepatic portal vein
What two nerves supply the stomach parasympathetically?
Anterior vagal trunk
Posterior vagal trunk
What range of nerves supply the stomach sympathetically?
T6-T9 segments of the spinal cord
How does vagal stimulation affect the pylorus?
Relaxation of the sphincter
How is the duodenum peritonised?
Retroperitoneal
What is the opening in the duodenum that allows pancreatic and bile fluids to enter?
Hepatopancreatic ampulla
What is the sphincter in the duodenum that controls the amount of pancreatic and bile fluids which enter?
Sphincter of Oddi
Describe the wall differences of the jejunum and the ileum
Jejunum - Thick + heavy
Ileum - Thin + light
Describe the vascularity of the jejunum and the ileum
Jejunum - Greater
Ileum - Lesser
Describe the vasa recta of the jejunum and the ileum
Jejunum - Long
Ileum - Short
Describe the arcades of the jejunum and the ileum
Jejunum - few large loops
Ileum - many short loops
Describe the fat in the mesentery of the jejunum and the ileum
Jejunum - less
Ileum - more
Describe the lymphoid tissue of the jejunum and the ileum
Jejunum - small
Ileum - numerous Peyer’s patches
What is the major blood vessel that supplies the jejunum and ileum?
SMA
What is the major blood vessel that drains the jejunum and ileum?
SMV
How is the ileum and jejunum supplied with nerves?
Superior myenteric plexus
What are the three differences between the small and large intestine?
Teniae coli
Haustra
Omental appendices
Where is the hepatic flexure located?
Between the ascending and transverse colon
Where is the splenic flexure located?
Between the transverse and descending colon
What two structures open up into the caecum?
Ileum
Ascending colon
What is McBurney’s points?
A point that is 1/3 of the way to the oblique line from the anterior superior iliac spine to the umbilicus
It is the location of the appendix base
What two arteries supply the ascending colon?
Ileocolic
Right colic
What two veins drain the ascending colon?
Ileocolic
Right colic
What three arteries supply the transverse colon?
Middle colic
Right colic
Left colic
What vein drains the transverse colon?
SMV
What two arteries supply the descending colon?
Left colic
Sigmoid
What vein drains the transverse colon?
IMV
What two arteries supply the sigmoid colon?
Left colic sigmoid
What vein drains the sigmoid colon?
IMV
What is the superior 1/3 of the rectum supplied with?
Superior rectal artery
What is the superior 1/3 of the rectum drained with?
Superior rectal vein
Where does lymph in the superior 1/3 of the rectum drained?
Inferior mesenteric vein
What is the middle 1/3 of the rectum supplied with?
Middle haemorrhoidal artery
What is the middle 1/3 of the rectum drained with?
Middle rectal vein
Where does lymph in the middle 1/3 of the rectum drained?
Inferior mesenteric
What is the inferior 1/3 of the rectum supplied with?
Inferior rectal artery
What is the inferior 1/3 of the rectum drained with?
Inferior rectal vein
Where does lymph in the inferior 1/3 of the rectum drained?
Internal iliac
What is the pectinate line?
The line which divides the upper 2/3 and the lower 1/3 of the anal canal
What are the four layers of the GI tract?
Mucosa
Submucosa
Muscular externa
Serosa/Adventitia
At what four junctions does the GI tract mucosa undergo an abrupt transition?
Gastro-oesophageal
Gastro-duodenal
Ileo-cecal
Recta-anal
What type of epithelium is found in the oesophagus?
Stratified squamous
What type of epithelium is found in the stomach?
Simple columnar
What are the four secretory cells of the stomach?
Chief cells
G cells
Parietal cells
ECL cells
What type of epithelium is found in the small intestine?
Simple columnar
In the epithelium of the stomach what two cell types are found?
Goblet cells
Epithelial cells
What does the submucosa of the duodenum contain?
Brunner’s glands
What is the role of Brunner’s glands?
To produce an alkaline substance to neutralise chyme
Are there Peyer’s patches in the duodenum?
Yes
What does the lamina propria of the ileum contain?
Peyer’s patches
Describe the muscualris externa of the colon
Smooth as no plicate circulars os intestinal vili present
Outer longitudinal layer forms the tenaie coli
Describe the histological features of the appendix
The mucosa has no villi
Fewer goblet cells to the colon
Ring of lymph follicles in the lamina propria
What are the four lobes of the liver?
Right lobe
Left lobe
Caudate
Quadrate
Where is the round ligament of the liver an embryological remnant of?
Umbilical veins
What is the porta hepatis?
A deep fissure in the inferior surface of the liver where ducts and neurovascular structures leave the liver
What are the five structures within the porta hepatis?
Portal vein
Hepatic artery
Bile duct
Lymphatic
Nerves
Where does the central vein in the liver drain to?
IVC
Where is bile produced?
Liver
Where is bile stored?
Gallbladder
How does bile enter the duodenum?
Sphincter of Oddi
What is Calot’s triangle?
A triangular space formed by the cystic duct, common hepatic duct and the inferior surface of the liver
What is contained within Calot’s triangle?
The cystic artery
What type of gland is the pancreas?
Endocrine
Exocrine
How is the pancreas peritonised?
Retroperitonised
What vein is formed posterior to the neck of the pancreas?
SMV
What two nerves supply the pancreas?
Coeliac trunk
SMA
What two veins drain the pancreas?
Splenic vein
SMV
What two nerves supply the pancreas?
Coeliac plexus
Superior mesenteric plexus
How is the spleen peritonised?
Retroperitoneal
What are the three structures in the hilum of the spleen?
Splenic artery
Splenic vein
Which part of the pancreas is related to the hilum of the spleen?
Tail
