Abdomen 1.2

Question 1

What nerves innervate the viscera of the abdominal cavity?

Answer 1

Sympathetic and parasympathetic

Question 2

Where do the sympathetic nerves come from?

Answer 2

coursing in the thoracic splanchnic nerves (from T5-T12 spinal cord levels) and lumbar splanchnics (upper lumbar levels)

Question 3

Where do the sympathetic nerves synapse?

Answer 3

• synapse largely in 3 major collections of ganglia:
  1. celiac
  2. superior mesenteric
  3. inferior mesenteric ganglia

Question 4

What gives rise to the the superior hypogastric plexus?

Answer 4

A nerve plexus continuing from this most inferior ganglion

Question 5

What does the superior hypogastric plexus provide?

Answer 5

Sympathetic innervation to pelvic viscera

Question 6

Where does parasympathetic innervation to the upper two thirds of the abdominal viscera come from?

Answer 6

The vagus nerve

Question 7

Where are the upper two thirds of the abdominal viscera derived from?

Answer 7

The foregut and midgut portions of the embryonic gut

Question 8

Where do the remaining portions of the abdominal and pelvic viscera (embryonic hindgut) receive parasympathetics from?

Answer 8

S2, S3, S4 via pelvic splanchnic nerves

Question 9

How do most of the autonomic fibres reach the viscera?

Answer 9

By travelling on the blood vessels originating from the celiac trunk and the superior and inferior mesenteric arteries

Question 10

Where do autonomic fibres to the bowel synapse? What is this?

Answer 10

• on ganglion cells of the enteric nervous system

- Intrinsic plexus of ganglia (myenteric and submucosal) for fine control of bowel function

Question 11

Where do preganglionic sympathetic fibers synapse?

Answer 11

In ganglia of the sympathetic trunk

Question 12

What is the course of preganglionic sympathetic fibres?

Answer 12

Course via splanchnic nerves to synapse in collateral ganglia such as celiac or superior mesenteric ganglion or pass directly to the adrenal medulla

Question 13

What does the parasympathetic fibers to the upper two-thirds of the abdominal viscera are conveyed by the vagus nerve do?

Answer 13

sends preganglionic fibers directly to the walls of the organs innervated

Question 14

How do these parasympathetic fibers end?

Answer 14

end in terminal ganglia in the visceral wall, which give rise to short postganglionic fibers

Question 15

How is pain sensation from the bowel conveyed?

Answer 15

afferent fibers whose nerve cell bodies reside in the spinal (dorsal root) ganglia of the T5-L2 spinal levels

Question 16

What is referred pain?

Answer 16

visceral pain is often referred to somatic regions of the body corresponding to the dermatomes supplied by the spinal cord segment that receives the visceral afferent (sensory) input

Question 17

What courses to the kidneys?

Answer 17

a rich plexus of sympathetic nerves arising from the superior mesenteric ganglion

Question 18

Where do sympathetics to the pelvic viscera arise from?

Answer 18

superior hypogastric plexus formed below the inferior mesenteric ganglion

Question 19

How do these nerves course?

Answer 19

on either side of pelvic viscera to the inferior hypogastric plexus

Question 20

Where does parasympathetic fibers to the kidneys arise from?

Answer 20

vagus nerve

Question 21

Where do the pelvic viscera and lower abdominal viscera receive their parasympathetic fibres from?

Answer 21

pelvic splanchnic nerves arising from S2, S3, and S4

Question 22

Where is renal colic felt?

Answer 22

The pain (renal colic) of a renal stone that passes from the kidney and into the ureter is usually felt from the loin to the groin as the stone works its way toward the urinary bladder in the pelvis

Question 23

What are the narrow points on the pathway of a renal stone?

Answer 23

1. ureteropelvic junction
2. midureter where it crosses the iliac vessels
3. the ureterovesical junction

Question 24

How is the pain of a renal stone conveyed?

Answer 24

by visceral afferents to the corresponding spinal (dorsal root) ganglia and then to the spinal cord (T11-L2); thus, the pain is localized to these dermatomes

Question 25

How does pain afferents from the abdominal viscera pass to the spinal cord?

Answer 25

by following the thoracic and lumbar splanchnic sympathetic nerves (T5-L2)

Question 26

Where are the nerve cell bodies of the afferent fibers from the viscera are located?

Answer 26

spinal ganglia of the respective spinal cord levels

Question 27

What is most visceral pain related to?

Answer 27

irritation from inflammation, ischemia, distention, or compression

Question 28

Which visceral pain is referred to both anterior and posterior body walls?

Answer 28

• stomach
• gallbladder
• spleen
• liver

Question 29

What do veins of the anterior abdominal wall provide?

Answer 29

important superficial anastomotic network of veins that returns blood to the heart

Question 30

What do the veins of the anterior abdominal wall include?

Answer 30

anastomoses between the superficial epigastric veins and lateral thoracic veins

Question 31

Where do the superficial epigastric veins drain?

Answer 31

into the inguinal ligament

Question 32

Where do the lateral thoracic veins drain?

Answer 32

axillary vein

Question 33

What do the inferior epigastric veins anastomose with on a deeper plane?

Answer 33

the superficial epigastric veins and the internal thoracic (mammary veins)

Question 34

What do anastomoses between superficial and deep veins allow?

Answer 34

ensure that venous blood can return to the heart via several different routes if necessary (which is important if a venous route is obstructed)

Question 35

Where does the inguinal canal extend?

Answer 35

from the deep inguinal ring to the superficial inguinal ring

Question 36

How is the spermatic cord related to the inguinal canal?

Answer 36

traverses this canal

Question 37

Where do indirect inguinal hernias occur?

Answer 37

• 75% of inguinal hernias
• occur lateral to the inferior epigastric vessels
• pass through the deep inguinal ring and inguinal canal,
• are enclosed within the internal spermatic fascia of the spermatic cord

Question 38

Where do direct inguinal hernias occur?

Answer 38

• medial to the inferior epigastric vessels (Hesselbach’s triangle)
• pass through the posterior wall of the inguinal canal
• are separate from the spermatic cord

Question 39

What do branches of the celiac trunk supply?

Answer 39

adult derivatives of the embryonic foregut and the spleen, a mesodermal derivative

Question 40

What does the celiac trunk give rise to?

Answer 40

1. left gastric artery
2. the common hepatic artery
3. the splenic artery

Question 41

What do the primary branches of the celiac trunk distribute arterial blood to?

Answer 41

1. liver
2. gallbladder
3. portions of the pancreas
   4 . spleen
4. stomach
5. proximal duodenum

Question 42

Where is pain secondary to the pathophysiologic processes common?

Answer 42

epigastric region

Question 43

What is in the epigastric region or refer pain there or dermatomes related to T5-T9 and T10 spinal levels?

Answer 43

stomach, duodenum, spleen, pancreas, liver, and gallbladder

Question 44

Where does the superior mesenteric artery supply blood to?

Answer 44

adult gastrointestinal tract derivatives of the embryonic midgut

Question 45

What are the areas that the superior mesenteric artery supplies blood to?

Answer 45

1. arteries to a portion of the pancreas
2. the distal duodenum
3. all of the small intestine
4. the appendix
5. the ascending colon
6. most of the transverse colon

Question 46

Which embryonic derivates does the inferior mesenteric artery supply?

Answer 46

embryonic hindgut derivatives

Question 47

What does the inferior mesenteric artery supply?

Answer 47

1. distal transverse colon
2. descending and sigmoid colon
3. superior portion of the rectum

Question 48

Are there anastomotic channels between the branches of the superior and inferior mesenteric arteries?

Answer 48

yes

Question 49

What happens if blood flow from one bowel region is compromised?

Answer 49

collateral flow from anastomotic branches usually can assist in supplying blood to the compromised region