Question | Answer |
What are the 3 main branches of the celiac trunk? (Foregut) | Splenic Artery
Left Gastric Artery
Common Hepatic Artery |
Splenic Artery | A -- Short gastric aa
B -- Left gastroomental aa |
Common hepatic artery | 1 - Proper hepatic artery
2 - Gastroduodenal artery |
Proper Hepatic | heads to liver
gives off right gastric artery |
Gastroduodenal artery gives off | right gastroomental and pancreaticoduodenal artery |
How are regions of the gut differentiated? | Based upon their blood supply |
What are the 3 regions of the gut? | Foregut
Midgut
Hindgut |
Midgut arterial supply | Superior mesenteric artery |
5 main branches of the superior mesenteric artery | Middle colic artery
Right colic artery
Ileocolic artery
Jejunal aa.
Ileal aa. |
Foregut contains | Abdominal esophagus
stomach
proximal duodenum
liver
pancreas
gallbadder
spleen |
Midgut contains | distal duodenum
jejunum
ileum
cecum
appendix
ascending colon
proximal 2/3 transverse colon |
Hind gut contains | Distal 1/3 transverse colon
descending colon
sigmoid colon
rectum |
Middle colic artery gives off | marginal artery |
Ileocolic artery gives off | posterior cecal artery
appendicular artery |
Ileal aa gives off | loops and arcades, vasa recta |
Loops and arcades and vasa recta are important for | absorption |
More loops and arcades in the __________ than the ____________. | Jujenum; ilium |
Hindgut arterial supply | inferior mesenteric artery |
Inferior mesentaric artery gives off | left colic artery
Sigmoid artery
superior rectal artery |
Left colic artery gives off | marginal artery |
Venous Drainage | Caval circulation
Portal circulation |
Caval circulation | Drains structures associated with abdominal wall (kidneys, gonads, musculature).
Drains into the inferial vena cava |
Caval circulation is made up of: | Single and Paired veins |
Single Caval Veins | Medial Sacral Vein |
Paired Caval Circulation | Inferior phrenic vein
Renal vein
Gonadal vein
Common Iliac vein
Lumbar vein |
Portal circulation is made up of : | portal vein
Portocaval anastomoses |
How many lumbar veins? | 2-4 |
Portal vein gives off | Superior mesenteric vein
splenic vein
left and right gastric vein
inferior mesentaric vein |
Inferior mesentaric vein gives off | superior rectal vein |
Beginning of gut formation | Week 4
Tube from the oropharynx to cloaca |
The endoderm makes up the _____________, ____________, and ____________. | lines of gut tube
Pancreas
Liver |
Splanchnic mesoderm makes up | muscular and connective tissue associated with the gut |
Tissue that covers teh gut tube is called the | Peritoneum |
A double later of the peritoneum that attaches to the gut tube to the body is called ________. | mesentery |
_______ attaches gut tube to dorsal body wall | Dorsal Mesentary |
____________ attaches gut tube to the ventral body wall. | Ventral mesentary. |
Attaches from tube to tube or tube to wall | Ligament |
Most of teh GI tract is ___________ | Intraperitoneal |
Intraperitoneal | surrounded by peritoneum |
Retroperitoneal | only the anterior surface is covered by peritoneum |
Are retroperitoneal organs mobile? | no |
Forgut embryonology | 1. Anterior-posterior outgrowths
2. Stomach rotates 90 degrees
3. 1st part of duodenum |
Anterior-posterior outgrowths | Dorsal -> greater curvature
Ventral -> lesser Curvature |
Dorsal mesentery gives off | spleen and pancreas (corsal and ventral buds)
Greater omentum |
When teh stomach rotates 90 degrees | Liver rotates to right hand side
Spleen rotates to the left side |
______________ forms the boundary of _____________ | Greater Omentum;Omental bursal |
Omental bursa | hole |
Lesser curvature is on the | right hand side3 |
lesser omentum has _____________ leading to the lesser sac | omental foramen (foramen of winslow) |
1st part of duodenum remains ___________ but the rest becomes ____________ | intraperitoneal
retroperioneal |
Transition to the midgut is where the ________ enters into the duodenum | common bile duct |
The liver and gall badder develop from _______ | the foregut as an outgrowth, the hepatic diverticulum |
Pancreas develops from the | dorsal and ventral pancratic buds |
The spleen develops withing | the dorsal mesogastrium |
Forgut undergoes a ______ clockwise rotation | 90 degree |
Most of the duodenum becomes | retroperitoneal |
Midgut Embryology I | U-shaped tube extends out to teh umbilcal cord
U- tube rotates counterclockwise 90 degrees |
Midgut Embroyology II | U-Tube begins to return to the abdominal cavity
Rotates another 180 degrees
duodenum becomes secondarily retroperitoneal |
Problems that can occur with midgut formation | Malrotation (volvulus)
Omphalocele |
Midgut embryology summary | midgut herniates out to umbilical cord
rotates a total of 270 degrees counterclockwise |
Hindgut embryology summary | Next block
cloaca differentiates into teh UG and GI systems |
Innervation of teh gut | Mostly autonomic (except esophagus) |
Sympathetic Nerves | Greater, lesser, least, and lumbar splanchnic nerves |
Parasympathethic nerves | Vagus nerve and Pelvic splanchnic nerve |
Foregut Innervation sympathetics | greater splanchnic nerve synapses with the celiac ganglion following the celiac trunk and its division |
Midgut Innervation Sympathetics | Lesser adn least Splanchnic Nerve synapsing with the superior mesentary and aortecosttal gaglia.They follow the superior associated arteries. |
Foregut Innervation parasympathetics | Vagus nerve and the afferent sensory is T6-T12 |
Midgut Innervation parasympathetics | Vagus nerve and the afferents follow spinal cord levels |
Hindgut innervation sympathetics | least splanchnic Nerve that synapses in the inferior mesentaric and hypogastric plexus that follows the blood supply. |
Hindgut innervation of parasympathetics | Pelvic Splanchnic off of S2-S4. Afferent nerves run to T12-S4 |