Abdomen II Flashcards
What does the term intraperitoneal mean?
- organs are completely covered with visceral peritoneum
- organs are attached to each other or to the abdominal wall by a double fold of peritoneum
What is the abdominal cavity bounded by?
- Diaphragm
- Anterolateral abdominal wall – external and internal oblique, transversus abdominis and rectus abdominis and pyramidalis
- Posterior abdominal wall - vertebral column, quadratus lumborum, PSOAS major and iliacus
- Pelvic inlet
What is the pelvic inlet bounded by?
- Posterior : sacral promontory
- Arcuate line
- Pectineal line and pubic crest
- Pubic symphysis is a secondary cartilaginous joint
What is everything below the pelvic inlet called and what structures are included?
- lesser pelvis
- (reproductive organs, terminal end of alimentary canal and bladder)
What 2 structures make up the abdominal cavity?
- greater pelvis and the abdomen proper
What is peritoneum?
- one continuous layer that is wrapped around all of the organs in the abdominal cavity
What is the difference between visceral and parietal peritoneum?
- Anything that touches an organ is known as visceral peritoneum and anything that is not touching an organ is called parietal peritoneum
What is peritoneal fluid made of?
- water, electrolytes,interstitial fluid, leukocytes and antibodies
Why is the peritoneal cavity open in females?
- space between the fimbriae and the ovary means that the peritoneal cavity in females is open
How does the peritoneum communicate with the exterior in females?
- via the vagina, uterus and uterine tubes in females
What does parietal peritoneum line?
- wall of the abdominal and pelvic cavities
What is the parietal peritoneum sensitive to?
- pain
- temperature
- touch
- pressure
What is the parietal peritoneum innervated by?
- T7-L1
What does the visceral peritoneum line?
- the abdominal and pelvic organs/viscera
What is the visceral peritoneum sensitive to?
- stretch
- tearing
What is the visceral peritoneum innervated by?
- afferent nerves that travel with autonomic supply to viscera it covers
Label this image
What does over distension of the visceral peritoneum lead to?
- pain
Where is the peritoneal cavity?
- The space between the parietal and visceral peritoneum
What is contained within the peritoneal cavity?
- peritoneal fluid
What is the greater sac?
- space of the peritoneal cavity, posterior to the anterolateral abdominal wall
Why is pain from the abdominal region poorly localized?
- Dermatomes share a convergent spinal root with the autonomic nerve which supply that particular organ
What is the foregut region supplied by?
- greater splanchnic nerves
- T5-T9
What is the midgut supplied by?
- lesser splanchnic nerves
- T9-T11
What is the hindgut supplied by?
- lumbar splanchnic nerves
- L1-L2
What is the lesser omentum and what does it do?
- double fold of peritoneum that attaches the liver to the lesser curvature of the stomach (hepatogastric ligament) and to the first part of the duodenum (hepatoduodenal ligament)
What is the lesser omentum derived from?
- ventral mesogastrium
What are the 3 things that a double fold of peritoneum can be called?
- mesentery, ligament or an omentum
What structures are located within the free edge of the lesser omentum?
- hepatic artery
- the portal vein
- the common bile duct
- lymph glands
- lymph vessels
- nerves
Where is the lesser sac and what is it continuous with?
- The lesser sac lies posterior to the stomach and is continuous with the greater sac through the epiploic foramen.
Label this image
What are the boundaries of the epiploic foramen?
roof:
floor :
posterior border :
anterior border :
- roof: caudate process of liver
- floor : hepatic artery and 1st part of duodenum
- posterior border : IVC
- anterior border : free border of lesser omentum
What are 5 subperitoneal structures?
- rectum lower 1/3
- urinary bladder
- distal ureters
- uterus
- uterine tubes
What is the mesentery?
- parietal peritoneum surrounding the small intestine comes together to form the mesentery
What are 13 intraperitoneal organs?
- stomach
- liver
- spleen
- tail of pancreas
- duodenum
- jejunum
- ileum
- caecum
- appendix
- transverse colon
- sigmoid colon
- sigmoid colon
- rectum (upper 1/3)
- ovaries
What are retroperitoneal organs (SAD PUCKER) ?
- suprarenal glands
- aorta + IVC
- Duodenum
- Pancreas
- Ureters
- Colon
- Kidneys
- Esophagus
- Rectum
What are the 4 secondary peritoneal organs?
- Duodenum (distal)
- pancreas
- ascending + descending colon
What does secondary peritoneal mean?
- during their embryological development they were intraperitoneal but then they migrated backwards and the layers of peritoneum split and the organ became retroperitoneal
What are the stomach and liver connected by?
- lesser omentum
What does the mesentery connect the small intestine to?
- the abdominal wall
What are the 2 types of peritoneal folds?
1) reflection of peritoneum that connects organs to another organ or abdominal wall
2) reflection of peritoneum that is raised form the body wall by underlying blood vessels,ducts + ligaments formed by obliterated fetal vesels
How is the liver attached to the anterior abdominal wall?
- via a double fold of peritoneum called the falciform ligament
What is the lateral umbilical fold?
- parietal peritoneum folding on top of the inferior epigastric artery
What is the midline parietal peritoneum fold?
- urachus
Label this image
with
1) urachus
2) lateral umbilical fold
3) medial umbilical fold
What is the function of peritoneal folds?
- route of blood vessels, lymphatics, nerves
- prevents effects of gravity
- immunity
What can peritoneal folds contain?
- contain varying amounts of fat
- intraperitoneal parts of organs (tail of pancreas is in splenorenal ligament)
What can the greater omentum do if an organ is infected?
- migrate and surround it
What is the developing foregut suspended from the anterior and posterior body by?
- anterior : ventral mesogastrium
- posterior : dorsal mesogastrium
Where does the liver develop?
- ventral mesentery
What does the liver split the ventral mesentery into?
- lesser omentum
- falciform ligament
What becomes the falciform ligament?
- parts connecting the developing liver to the anterior abdominal wall becomes the falciform ligament
What structures run in the free edge of the lesser omentum?
- common bile duct
- proper hepatic artery
- hepatic portal vein
What is the lesser omentum divided into?
- two parts :
- The hepatogastric ligament which runs from the liver to the stomach
- Hepatoduodenal ligament which runs from the liver to the duodenum
What organ is attached to the posterior layer of the greater omentum?
- transverse colon
From which embryonic mesentery does the greater omentum arise from?
- dorsal mesentery
Label this image
How do the greater sac and lesser sac form in embryological development?
- The stomach starts to rotate around its axis and as it rotates the peritoneal cavity is divided into two parts : greater sac and lesser sac
Around what axis does the stomach rotate during development and where do the pyloric and cardiac parts move?
- anteroposterior axis
- pyloric part moves to the right and up
- cardiac part moves to the left and down
What is the lesser sac’s function?
- allows stomach to expand
How are the greater and lesser sac connected?
- through the epiploic foramen (of Winslow)
What does the transverse mesocolon divide the peritoneal cavity into?
- supracolic and infracolic compartments
What does the mesentery do?
*
What does the mesentery contain?
- superior mesenteric artery and vein and their branches
What structures are located at the proximal and distal ends of the root?
- duodenal flexure
- ileocecal junction
What are these 2 arrows pointing to?
- root of the sigmoid mesocolon (bottom arrow)
- root of the mesentery (top arrow)
What is the greater omentum?
- double fold of peritoneum folded back on itself (4 layers) forming an apron like structure that hangs from the greater curvature of the stomach
What happens if you separate the layers of the greater omentum?
- you get access to the lesser sac through the inferior recess
Where does the spleen develop?
- dorsal mesogastrium
What does the developing spleen divide the dorsal mesogastrium into?
- gastrosplenic ligament (passing stomach to spleen)
- lienorenal ligament (passing from spleen to left kidney)
What is the falciform ligament continuous with?
- visceral peritoneum surrounding the liver and the lesser omentum
What is the falciform ligament derived from?
- ventral mesogastrium
What is a peritoneal recess?
- a region where the peritoneum is reflected away from the posterior abdominal wall to form a pouch or a recess
- areas where fluid or pus can potentially collect
Where does the esophagus extend from and to?
- from the pharyngo-esophageal junction C6 to cardiac orifice of the stomach T11
What is the function of the esophagus?
- transport food from pharynx to stomach
At what vertebral level does the esophagus pass through the diaphragm?
- T10
What are the 2 sphincters of the diaphragm?
- upper esophageal sphincter
- lower esophageal sphincter
What muscle acts as the upper esophageal sphincter?
- inferior pharyngeal constrictor
What structures compress the esophagus when it passes through the diaphragm?
- thyroid cartilage
- aortic arch
- left main bronchus
What is the function of paracolic gutters?
- provide pathways for the flow of ascitic fluid and the spread of intraperitoneal infections
- pathways for the spread of tumour cells that have sloughed from the ulcerated surface of a tumour and entered the peritoneal cavity
Where is the subphrenic space?
- Space between the upper surface of the right lobe of the liver and below the diaphragm.
Where is the hepatorenal pouch of morrison?
- Space between the liver and the right kidney
Where is the rectovesical pouch?
- Space between rectum and bladder (male)
Where is the uterovesical pouch?
- Space between uterus and bladder (female)
Where does purulent material (consisting of or containing pus) in the abdomen, which has been transported along the paracolic gutters, pool depending on whether the patient is standing upright or lying supine?
- paracolic gutters - supine
- in the pouches of douglas or rectovesical when standing
What are the 4 layers of the esophagus?
- mucosa
- submucosa
- muscularis externa
- adventitia
What kind of cells are found in the mucosa of the esophagus and what is their function?
- non-keratinized stratified squamous epithelium
- secretes mucus
- protects against wear & tear
What is the muscularis externa divided into?
- 1) superior third : skeletal muscle
- 2) middle third : skeletal and smooth muscle
- 3) inferior third : smooth muscle
What is the arterial supply of the upper third of the esophagus?
- inferior thyroid artery
What is the arterial supply of the middle third of the esophagus?
- thoracic aorta
What is the blood supply of the middle third of the aorta?
- left gastric artery
What is the left gastric artery a branch of?
- the celiac trunk
What is the innervation of the esophagus?
- mainly through right and left vagus
Where are the 2 origins of the esophageal plexus?
- vagus nerve (CN X)
- parasympathetic
- general sensation fibers
- nerves from the cervical and thoracic sympathetic trunk
- sympathetic fibers
- pain fibers
Label this diagram
What is the lymphatic drainage of the esophagus?
- birectional
- upwards to deep cervical lymph nodes
- downwards to juxta esophageal lymph nodes
Where are the juxtaesophageal lymph nodes?
- anterior to esophagus in posterior mediastinum
What are the 3 functions of the stomach?
- storage of ingested food
- regulate rate of emptying into small intestines
- mechanical and chemical breakdown of food
In what region is the stomach found in?
- umbilical or epigastric
What are the 4 factors that can change size, shape and position of the stomach?
- body types
- diaphragmatic movements
- contents
- position
What is the cardia?
- opening of esophagus into stomach
What is the pylorus for?
- tonically contracted to control emptying of chyme into duodenum
What does gastric emptying occur through?
- pylorus
What creates the cardiac notch?
- the stomach rotating around 90º around its longitudinal axis and anticlockwise around the dorsal-ventral axis
How does the greater curvature arise?
- As the stomach rotates the original surface which was posterior undergoes rapid growth and it becomes the greater curvature
What is the lower esophageal sphincter?
- thickening of muscle that prevents the backflow of food
What are the 2 parts of the pylorum called?
- antrum and canal
What is the fucntion of the cardial orifice?
- cardiac sphincter prevents backflow of food and digestive enzymes to esophagus
Label this image with
1) greater curvature
2) lesser curvature
3) body
4) fundus
5) pylorus
6) duodenum
7) esophagus
8) cardia
9) angular incisure
Where does the foregut extend from and to?
- extends from the oesphagus to the major duodenal papilla of the duodenum
At what vertebral level is the cardiac orifice?
- T10
At what vertebral level is the pharyngo-esophageal junction?
- C5-C6
What are the 3 muscular layers of the stomach and what are their functions?
- 1) inner oblique - mechanical food breakdown
- 2) middle circular layer - forms pyloric sphincter
- 3) outer longitudinal layer - moving bolus towards pylorus through muscular shortening
Label this image with the layers of the stomach
What is the function of the gastric rugae?
- allows stomach to expand
What are the 3 types of gastric glands and what do they secrete?
- 1) cardiac glands : mucus
- 2) fundic glands : Hcl
- 3) pyloric glands : gastrin
What type of muscle is in the muscularis mucosae?
- smooth muscle
What types of cells are in the mucosa?
- columnar epithelium
What is the auerbach plexus controlled by?
- autonomic system
What is a peptic ulcer?
- open lesion in mucosa lining
What is the cardiac notch?
- Angle between the oesophagus and the fundus of the stomach
What is the angular incisure?
- Notch of lesser curvature that marks the commencement of pyloric antrum
What are the 3 locations of peptic ulcers?
- esophagel
- gastric
- duodenal
What are the 3 causes of peptic ulcers?
- H. pylori
- NSAIDs
- stress
What 8 structures make up the foregut?
- esophagus
- lower respiratory tract
- stomach
- duodenum
- liver
- gallbladder
- pancreas spleen
What 7 structures make up the midgut?
- duodenum
- jejunum
- ileum
- caecum
- appendix
- ascending colon
- transverse colon
What 4 structures make up the hindgut?
- transverse colon
- descending colon
- sigmoid colon
- rectum
What does the celiac trunk supply?
- foregut
What is the midgut supplied by?
- superior mesenteric artery
What is the hindgut supplied by?
- inferior mesenteric artery
What are the 3 main branches of the celiac trunk?
- common hepatic
- left gastric
- splenic
At what vertebral level does the coeliac trunk typically lie?
- T12
What are the 3 main arteries that arise from the celiac trunk?
- Common hepatic artery
- Left gastric artery
- Splenic artery
What does the left gastric supply?
- the lesser curvature
What is the short gastric artery a branch of?
- splenic artery
Where does the short gastric artery pass?
- through gastrosplenic ligament
Where does the right gastric run?
- along the lesser curvature in the lesser omentum
Where does the right gastro-omental run?
- along greater curvature in greater omentum
What 2 arteries is the greater curvature supplied by?
- right and left gastro-omental
Label this image
What does the cystic artery supply?
- the gallbladder and cystic duct
The left gastric artery forms an anastomosis with the right gastric along which curvature of the stomach?
- lesser curvature
What curvature of the stomach do the left and right gastroepiploic arteries supply?
- greater curvature
Where does the splenic artery run in relation to the stomach and pancreas?
- behind the stomach
- superior to pancreas
Where do the short gastric arteries rise?
- splenic artery
Where do the gastroduodenal arteries arise?
- common hepatic artery
What does lymphatic drainage of the stomach follow and into what 2 nodes?
- follows the arteries along the lesser and greater curvatures (gastric nodes and gastroepiploic nodes, respectively)
Where do the lymphatic vessels of the stomach drain?
- coeliac nodes
What is the function of parasympathetic nerves in the stomach?
- secretomotor to gastric glands
- motor to muscular walls
What is the function of the sympathetic system in the stomach?
- motor fibers to pyloric sphincter
- also carries pain fibers to spinal cord
What is the parasympathetic innervation of the stomach?
- the left and right vagus nerves
What is the sympathetic innervation of the stomach and at what vertebral level?
- greater splanchnic nerves (T5 –T9) which pass through the coeliac plexus.
How does the rotation of the stomach affect the position of the left and right vagus nerve?
- right vagus is on the lesser curvature
- left vagus is on the greater curvature
