GI vascular and innervation

Question 1

describe the embryonic derivatives of the gut vasculature-3

Answer 1

1. caudal foregut
   
   1. supplied by celiac trunk(celiac artery)
2. midgut
   
   1. supplied by the meseteric artery
3. hindgut
   
   1. supplied by the inferior mesenteric artery

Question 2

what does the embryonic forgut form?

Answer 2

1. abdominal portion of the esophagus
2. stomach
3. duodenum, with respect to its union with the common bile and pancreatic ducts
4. Liver and gallbladder
5. pancreas
6. spleen- not digestive, but closely related via proximity

Question 3

which branches of the celiac trunk supplying derivatives of the embryonic caudal foregut?

Answer 3

1. left gastric artery
   
   1. goes to
      
      1. STOMACH
      2. LOWER ESOPHAGUS
2. splenic artery
   
   1. goes to
      
      1. neck, body and tail of PANCREAS
      2. SPLEEN
      3. STOMACH
3. Common hepatic artery
   
   1. gastroduodenal artery
      
      1. STOMACH
      2. head of PANCREAS
      3. DUODENUM
   2. proper hepatic artery
      
      1. LIVER
      2. GALLBLADDER
      3. STOMACH

Question 4

list three locations and consequences of ulcerations with regard to the duodenum

Answer 4

1. duodenal ulcers
   
   1. posterior
      
      1. erode directly into the gastroduodenal artery or more commonly on posterior superior pancreaticoduodenal artery
         
         1. fatal hemorrhage
   2. anterior
      
      1. erode into the peritoneal cavity
      2. peritonitis thereby causeing adhesion of greater omentum

Question 5

what does the embryonic midgut form in adults?

Answer 5

1. duodenum
2. jejunum
3. ilum
4. cecum
5. appendic
6. ascending colon
7. transverse colon

Question 6

describe the vasculature of the midgut

Answer 6

• branches of the superior mesenteric artery
  
  • inferior pancreaticoduodenal artery
    
    • head of the PANCREAS
    • DUODENUM
  • intestinal branches
    
    • JEJUNUM
    • ILEUM
  • middle colic artery
    
    • TRANSVERSE COLON
  • right colic artery
    
    • ASCENDING COLON
  • ileocolic artery
    
    • terminalILEUM,
    • CECUM,
    • ascending COLON
    • appendicular artery
      
      • APPENDIX

Question 7

DESCRIBE THE structures formed from the hindgut

Answer 7

• descending colon
• sigmoid colon
• rectum
• anal canal

Question 8

describe the vasculature of the hindgut

Answer 8

• inferior mesenteric artery
  
  • left colic artery
    
    • DESCENDING COLON
  • sigmoid arteries
    
    • SIGMOID COLON
  • superior rectal artery
    
    • RECTUM
    • ANAL CANAL

Question 9

branches where, allow for anastomose between the midgut and hindgut arteries?

Answer 9

1. marginal artery
   
   1. runs parallel to the colon
   2. collateral circulation

Question 10

describe the venous drainage of the abdominal organs

Answer 10

• venous drainage from the abdominal GI tract and spleen enters the hepatic portal vein for transport to the liver

1. hepatic portal vein- has two main contributions
   
   1. splenic vein
      
      1. ​the inferior mesenteric drains into the splenic vein
   2. superior mesenteric vein
   3. minor but clinically relevantportacaval anastomoses
      
      1. connect the hepatic portal vein to systems of the inferior venae cava
      2. become dilated when flow resistance patients with cirrhosis-portal hyotension

Question 11

describe the route of cancer spreading from the GI tract

Answer 11

the blood flows from the GI tract to the liver first. This means that cancer from the GI tract often metastasizes to the liver

Question 12

list some locations affected by portal hypertension

Answer 12

portacaval anastomoses taht amay enlarge include

1. lower esophagus
   
   1. as esophageal varicies
      
      1. may be fatal
2. anal canal
   
   1. hemorrhoids
3. paraumbilical region-caput medusae
   
   1. varicose veins radiating outward from the umbilicus

Question 13

describe the two nodes categorized in the flow of lymphatic fluid. list the categories, organs and important structures

Answer 13

1. pre-aortic nodes
   
   1. where
      
      1. celiac
      2. superior mesenteric
      3. inferior mesenteric
   2. organs
      
      1. GI tract
      2. accessory organs
   3. unit to form intestinal trunk
2. para-aortic
   
   1. where
      
      1. lumbar
   2. organs
      
      1. body wall
      2. kidneys
      3. adrenal glands
      4. testes/ovaries/ uterus/uterine tubes
   3. collect to form the right lumbar trunk** and the **left lumbar trunk

• confluence of all trunks appears as CISTERNA CHYLI

Question 14

describe the sympathetic nervous innervation of abdominal organs

Answer 14

• consists
  
  • preganglionic nerve fibers
    
    • reach the prevertebral ganglia through splanchnic nerves
  • postganglionic nerve fibers
    
    • from cell bodies in prevertebral ganglia
    • follow arteries to organs
    • location
      
      • celiac trunk
        
        • ​CELIAC GANGLIA
      • superior mesenteric artery
        
        • ​SUPERIOR MESENTERIC GANGLION
      • inferior mesenteric artery
        
        • ​INFERIOR MESENTERIC GANGLION
      • renal arteries
        
        • ​AORTICORENAL GANGLIA

Question 15

list the splanchnic nerves from contributions from the spine and destination

Answer 15

1. thoracic splanchnic nerves
   
   1. nerves
      
      1. greater splanchnic- T5-9
      2. lesser splanchin (T10-11)
      3. least splanchnic-T12
   2. location
      
      1. forgut (celiac trunk)
      2. midgut (superior mesenteric artery) territory
2. lumbar splachnic nerves
   
   1. nerves
      
      1. L1-2 (ocassionally L1-3)
   2. location
      
      1. hindgut ( inferior mesenteric artery)

Question 16

desceib the flow of autonomic nerve fiber to visceral organs. Hint ( they follow blood vessels)

Answer 16

1. celiac ganglia nerve fibers
   
   1. route
      
      1. follow celiac trunk branches
   2. innervate
      
      1. forgut derivatives
2. aorticorenal ganglia fibers
   
   1. route
      
      1. follow renal artery branches
   2. innervate
      
      1. kidneys
      2. adrenal glands
3. superior mesenteric ganglia
   
   1. route
      
      1. follow superior mesenteric artery
   2. innervate
      
      1. midgut derivatives
4. inferior mesenteric nerves ganglia
   
   1. route
      
      1. mesenteric artery
   2. innervate
      
      1. hindgut

Question 17

describe the parasympathetic innervation of the abdominal cavity

Answer 17

two main sources: vagus and pelvic

1. vagus nerves-CX
   
   1. route
      
      1. enter abdomen through esophageal haitus
         
         1. anterior and posterior vagal trunks
            
            1. formed esophageal plexus
            2. supply preganglionic parasympathetic input to ganglion cells located near or within the wall of tthe visceral sttructure
   2. innervate
      
      1. forgut
      2. midgut
2. pelvic splanchnic-S2-S4
   
   1. route
      
      1. leave sacral spinal cord through anterior rami** and send **preganglionic fibers to hindgut
   2. innervate
      
      1. hindgut

Question 18

compare the functions of the sympathetic and parasympthetic autnoimc nervous inputs on thte abdominal contents

Answer 18

both manipulate the enteric nerous system

1. sympathetic
   
   1. vasoconstriction
   2. reduced glandular secretion
   3. reduced peristalsis
2. parasympathetic
   
   1. increase glandular secretion
   2. increase peristalsis, through smooth muscle

Question 19

what type of fibers accompany sympathetic nerves and carry pain?

Answer 19

visceral afferent fibers accompany sympathetic nerves and carry parin from the abdominal viscera to the spinal cord.

Question 20

describe the nerves involved with the reffered pain at the following locations.

Answer 20

1. GREATER SPLANCHNIC NERVE T5-T9
   
   1. forgut
      
      1. stomach, liver, gallbladder, pancrease, duodenum, spleen
   2. where
      
      1. dermatomes
2. PHRENIC NERVE
   
   1. what organs
      
      1. diaphragmatic pleura
         
         1. pleuritis
      2. peritoneum
         
         1. cholecystitis
      3. ruptured spleen
   2. where
      
      1. ipsilateral shoulder
   3. why
      
      1. afferentt fibers of the phrenic nerve (C3,4,5) enter the same spinal cord segments as the supraclavicular nerves which supply cutaneous innervation to the shoulder.