Upper GI Flashcards
composition of esophagus muscle wise
upper 1/3 is skeletal muscle, lower 2/3 is smooth muscle - inner layer is smooth circular and outer is longitudinal
where is the esophagogastric junction
left of T11
junction of stomach and esophagus
- cardia
2. z line
significance of the z line
mucosa changes from stratified squamous to simple columnar epithelium, superior to the line diapgragmatic musculature surrounding esophagus functions as inferior esophageal spincter
blood supply ABDOMINAL esophagus
- branches of left gastric artery
2. inferior phrenic arteries (off abd aorta)
sympathetic innervation of esophagus
greater splanchnic nerves
parasympathetic innervation of esophagus
vagus nerve (esophageal plexus)
2 constriction points in esophagus
- thoracic constriction (bronchoaortic)
2. diaphragmatic constriction
para-esophageal hernia
cardia remains in place, z line remains in place, fundus of stomach pops through diaphragm LESS COMMON
sliding esophageal hernia
abdominal portion of esophagus, cardia, and maybe some fundus of stomach slide above diapgragm (z line displaced) MORE COMMON
causes of GERD
- sliding hiatal hernia
2. decreased tone of lower esophageal spincter
causes of peptic ulcers
- mucosa exposed to gastric acid
2. H pylori
what structures lie posterior to the pyloric spincter/first part of duodenum?
portal vein, bile duct, neck of pancreas, gastroduodenal artery with its anterior and posterior superior pancreaticoduodenal arteries
what structures lie posterior to the pylorus of the stomach
celiac trunk, aorta
lymphatic drainage of the stomach
gastric and pyloric lymph nodes
venous drainage of stomach
celiac veins to the portal venous system
blood supply stomach
celiac trunk as the left gastric, splenic (gastroomental, short gastric), right gastric, gastroduodenal as the right gastroomental)
psns innervation stomach
vagus nerves
sns innervation stomach
greater splanchnic nerves
what is the gastric canal
groove between rugae and lesser curvature
3 muscle layers of stomach
- outer longitudinal layer
- middle circular layer
- inner oblique fibers
=muscularis extrema
stomach located where
left hypochondrium, left epigastric and umbilical regions
what ligament contains portal triad
hepatoduodenal ligament in the lesser omentum
cardia
esophagogastric junction
fundus
above and to left of cardia may have air
cardiac notch
between cardia and fundus
pyloric antrum
begins at angular notch
pyloric canal
narrower portion of pylorus
pylorus
distal spincteric region
what is the celiac ganglia
fibrous bundle that receieve fibers from greater splanchnic nerve, and send out postganglionic fibers called celiac plexus
length of small intestin
6-7 meters
characteristics of the 1st part of duodenum
LACKS plicae circularis, peritonealized, anterior to bile duct,portal vein, gastroduodenal artery, prone to ulcers bc pancreatic bicarb doesnt dump here to neutralize gastric contents
characteristics of 2nd part of duodenum
secondarily retroperitoneal, plicae circulares PRESENT, common bile duct and main pancreatic duct open into duodenal papilla (duodenopancreatic ampulla of vater) - END OF FOREGUT
characteristic of 3rd part of duodenum
CIRCULAR FOLDS PRESENT, secondarily retroperitoneal, posterior to SMA, crosses L3, BEGINNING OF MIDGUT
characteristic of 4th part duodenum
CIRCULAR FOLDS PRESENT, to left of midline secondarily retroperitoneal, supported by suspensory ligament of duod = ligament of trietz, ends at duodojejunal flexures
where is the ligament of trietz
smooth muscle that passes from the right crus of diaphragm around the esophagus and attaches to the muscle in duod at duodenojejunal flexure - IS A FIXED POINT IN POST ABD WALL
nutcracker position
3rd part of duodenum is between the origin of SMA and aorta (neck of pancreas is anterior to aorta and superior to 3rd part)
division of foregut, midgut, hindgut
FOREGUT: esophagus to duodenal papilla, blood celiac trunk, sympathetics greater splanchnic n, parasympathetics vagus n
MIDGUT: duodenal papilla to 2/3 of transverse colon, blood SMA, sympathetics lesser splanchnics, parasympathetics vagus n
HINDGUT: 1/3 transverse colon to rectum, blood IMA, sympathetics lumbar splanchnics, parasympathetics pelvic splanchnic (S2-S4)
lymphatic drainage duod
pyloric nodes, SM lyphnodes
specific blood to duod
- superior A&P pancreaticoduodenal from gastroduodenal A
- inferior A&P pancreaticoduodenal from SMA
where does jejunum begin
L2 at duodenojejunal flexure on left side
where does ileum end
ileocecal junction
what is meckel’s diverticulum?
leftover of umbilical cord! remnant of proximal part of yolk sac that follows the rule of 2’s: 2 inches long, 2 feet from ileocecal junction, and only occurs in 2% of population
position of jejunum and ileum
jejunum: ULQ
ileum: LRQ
distinguishing characteristics of jejunum
jejunum: deeper red/greater vascularity, 2-4 cm, thick and heavy, long vasa recta, few large archades, less fat in mesentery, large circular folds, few peyer’s patches (lymphoid nodules)
distinguishing characteristics of ileum
paler pink, 2-3 cm, thin and light, short vasa recta, more small archades, more fat in mesentery, low and sparce circular folds, has more peyer’s patches
lymphatic drainage of jejunum and ileum
superior mesenteric and ileocolic lymph nodes
