GI organs Part 1 Flashcards
What are the organs apart of the GI tract?
what are the associated GI tract organs?
organs apart of the GI tract:
- Esophagus
- small intestine
- colon
- rectum
- anal canal
organs associated with the GI tract:
- Spleen
- pancreas
- liver
- gall bladder
What are the 4 abdominal planes? where are they located? and what are they passing through?
Transpyloric plane: L1
-passes through the pyloric sphincter
Subcostal Plane: L2-3
-passes inferior to the costal margain
Transtubercular plane: L5
-passes through the iliac tubercles
Interspinous plane: S2
-passes through the ASIS
Components of the Esophagus
Passes through the esophageal hiatus at the level of T10
Enters the stomach at the cardiac orifice at level of T11
Cardiac notch seperates esophagus from fundus of stomach
Inferior esophageal sphincter is a physiologic not an anatomical sphincter because the diaphragm works as the sphincter
Where are the 3 constrictions of the esophagus?
Superiorly: level of cricoid cartilage at the juncture with the pharynx
Middle: crossed by aorta and left main bronchi
Inferiorly: diaphragmatic sphincter
what are the two different Hiatal Hernias?
Para-esophageal hiatal hernia:
- Cardia of stomach in normal position
- Peritoneum and fundus of stomach are anterior to esophugus and pinched in with the diaphragm
Sliding hiatal hernia:
-Esophagus, cardia of stomach and fundus of stomach protrude through esophageal hiatus up into the diaphragm
Characteristics, parts, and borders of the Stomach?
Volume is 2-4 liters
Location is the right and left upper quadrants
Left end fixed at level of T10-11
Right end fixed at level of L1
Parts: Cardia (connected to esophagus)
fundus (superior to cardiac orfice at the level of 5th rib), body (portion between fundus and pylorus),
antrum (wide portion of pylorus),
pylorus canal,
pylorus sphincter (normally closed. and regulates what goes into duodenum)
Inferior border: greater curvature where the greater omentum attaches
Superior border: lesser curvature where the lesser omentum attaches
Relationships of the stomach to the other organs?
Anterior: anterior abdominal wall, diaphragm, and the left lobe of the liver
Posterior: diaphragm, spleen, left suprarenal gland, left upper kidney, pancreas, transverse colon, transverse mesocolon, and omental bursa
Purpose of the Gastric Vagotomy? and the three types
Truncal Vgotomy: denervates nerve supply to all of stomach plus most of G.I. tract and liver
Proximal gastric vagotomy: denervates branches of vagus nerve going only to stomach
Selective Proximal vagotomy: specifically denervate area of stomach in which parietal cells are located (fundus and cardia)
-good for patients with patent gastric ulcers
Characteristics of the Duodenum and how many parts are their?
Begins at the pylorus and ends at the duodenojejunal junction (level of L2)
-length is 10”
1st part: intraperitoneal, 1: long and travels superior and to the right associated with the hepatoduodenal ligament
2nd part: retroperitoneal, 3-4”
3rd part: retro peritoneal 4”
4th part: retroperitoneal and 1” that joins with the jejunum (duodenojejunal junction or flexure)
what dumps into the 2nd part of the Duodenum?
Contains the hepatopancreatic ampulla and Major duodenal papilla which allow for the bile and pancreatic enzymes to enter the duodenum
Relations of 2nd part of the duodenum
Anterior:
- gallbladder
- right lobe of the liver
- transverse colon
- coiled of small intestine
Posterior:
- Hilum of right kidney
- right ureter
Lateral:
- right colic flexure
- ascending colon
- right lobe of the liver
Medial:
- Head of pancreas
- Bile and pancreatic ducts
Relations of the 3rd part of duodenum
Anteriorly:
- root of the mesentery of the small intestine
- superior mesenteric vessels contained within the mesentary
- coils of the jejunum
Posterioly:
- the right ureter
- the right psoas muscle
- inferior vena cava
- aorta
Superiorly:
-Head of the pancreas
Inferiorly:
-coils of jejunum
Relationships of the 4th part of the duodenum
Posteriorly:
- left crus of diaphragm
- left psoas major muscle
- left sympathetic trunk
- left renal vessels
- left gonadal vessels
- left supra renal vein
- inferior mesenteric vein
Right side:
-Uncinate process of pancreas
Left side:
-left kidney and ureter
superiorly:
-body of pancreas
what is the Ligament of Treitz
Suspensory muscle that attaches the 4th part of the duodenum to the posterior abdominal wall
-functions to widen the openings of this portion of the duodenum
anchors 4th part of the right crus of the diaphragm
can be torn during a MVA and high impact collision
Characteristics, location, and arterial supply of the Jejunum
Location: left upper quadrant
Intraperitoneal organ supported by the mesentery
Proximal 2/5s of the small intestine
Contains mucosal folds called plicae circulares that absorb nutrients
Mesenteric fat increases from proximal to distal (less here than in ileum)
supplied by (single) arterial arcades with long vasa recta
Characteristics, location, and arterial supply of the ileum
Location: right lower quadrant
intraperitoneal: supported by the mesentary
Distal 3/5s of the small intestine
Supplied by compound arterial arcades (layered) with short vasa recta
more fat here in mesentary
What is the mesentary and its relations and functions
Attaches the Jejunum and ileum to the posterior body wall
consists of 2 layers of peritoneum
Contains superior mesenteric arteries and veins, lymph nodes, fat and autonomic nerves
Relations: Crosses the 3rd/4th parts of the duodenum, aorta, IVC, right ureter, right psoas major and right gonadal artery and vein
what are the parts and the external characteristics of the large intestine?
Parts: Cecum, appendix, ascending colon, transverse colon, descending colon, and sigmoid colon
length is approximately 5 feet
begins at the ileocecal junction
External features:
- 3 tena coli (longitudinal bands of smooth muscle)
- Haustra (make up the segments)
- Appendices epiploicae (store fat)