Anatomy: abdominal pain and likely sources

Question 1

Roughly how long is the small intestine?

Answer 1

7m

Question 2

What are the names of the three parts of the small intestine?

Answer 2

Duodenum (short), jejunum (around 3m) and ileum (around 4m)

Question 3

What is the large intestine made up of?

Answer 3

The colon: caecum, appendix, ascending colon, transverse colon, descending colon and sigmoid colon
The rectum, anal canal
and anus

Question 4

What are the three divisions of the abdominal organs?

Answer 4

Foregut, midgut and hindgut

Question 5

What abdominal organs are in the foregut?

Answer 5

Oesophagus to mid-duodenum

Liver, gallbladder, spleen and 1/2 pancreas

Question 6

What abdominal organs are in the midgut?

Answer 6

Mid-duodenum to proximal 2/3rd of transverse colon

1/2 pancreas

Question 7

What abdominal organs are in the hindgut?

Answer 7

Distal 1/3rd of the transverse colon to proximal 1/2 of the anal canal

Question 8

What are the 9 regions of the abdominal cavity?

Answer 8

Right & left hypochondrium, epigastric, right & left lumbar, umbilical, right & left inguinal and pubic

Question 9

Where are the lines that divide the 9 regions?

Answer 9

Mid-clavicular, subcostal and trans-tubercular planes

Question 10

What are the 4 quadrants of the abdominal cavity?

Answer 10

Right & left upper quadrants

Right & left lower quadrants

Question 11

Where are the divisions for the 4 quadrants?

Answer 11

Median and trans-umbilical planes

Question 12

Name the muscles of the anteriolateral abdominal wall

Answer 12

Rectus abdominis, external oblique, internal oblique and transversus abdominis

Question 13

How do the abdominal muscles guard the abdominal organs when injury threatens?

Answer 13

They contract

also happens in peritonitis

Question 14

What is the peritoneum?

Answer 14

A thin, transparent, semi-permeable, serous membrane that lines the walls of the abdominopelvic cavity and organs

Question 15

What is the parietal peritoneum?

Answer 15

Peritoneum that is in contact with the body wall (soma)

Question 16

What is the visceral peritoneum?

Answer 16

Peritoneum that is in contact with the organs

Question 17

Explain the nerve supply to the peritoneum

Answer 17

The peritoneum is sensitive as it has a nerve supply
The parietal peritoneum is supplied by the same nerves as the body wall
The visceral peritoneum is supplied by the same nerves as the organs

Question 18

What is the peritoneal cavity?

Answer 18

Thin, enclosed space between the parietal and visceral layers that contains a small amount of peritoneal fluid

Question 19

What is peritonitis and what can cause it?

Answer 19

Inflammation of the peritoneum

Cause: blood, pus or faeces in the peritoneal cavity

Question 20

What are the 3 organ classes that are dependent on their relationship with the peritoneum?

Answer 20

Intraperitoneal, retroperitoneal and with a mesentery

Question 21

What defines an intraperitoneal organ?

Answer 21

Almost completely covered in visceral peritoneum

Minimally mobile

Question 22

What organs are intraperitoneal?

Answer 22

The stomach, the first 5 centimeters and the 4th part of the duodenum, jejunum, ileum, caecum, appendix, transverse colon, sigmoid colon, and the upper 1/3 of the rectum, as well as, the liver, spleen, and the tail of the pancreas.

Question 23

What defines a retroperitoneal organ?

Answer 23

Only has visceral peritoneum on its anterior surface

Located in the retroperitoneum

Question 24

What organs are retroperitoneal?

Answer 24

Supradrenal glands, ureter, kidney, bladder, aorta, inferior vena cava, part of the oeosphagus and part of the rectum
Pancreas, duodenum (not first part), ascending and descending colon
SAD PUCKER

Question 25

What defines an organ with a mesentery?

Answer 25

Covered in visceral peritoneum Visceral peritoneum wraps behind the organ to form a double layer - mesentery Mesentery suspends the organ from the posterior abdominal wall - very mobile

Question 26

What are condensations of the peritoneum?

Answer 26

Double layers that attach organs to each other or to the abdominal wall They are secondary to growth and rotation of the GI tract during embryology

Question 27

Name 4 condensations of the peritoneum

Answer 27

Falciform ligament Greater and lesser omentum Mesentery of small intestine

Question 28

How do the two sacs of the peritoneal cavity, the lesser and greater sac, communicate?

Answer 28

Omental foramen

Question 29

Where does the portal triad lie?

Answer 29

In the free edge of the lesser omentum

Question 30

There are pertioneal pouches formed due to the peritoneum draping over the superior aspect of the pelvic organs. How many pouches do males and females have?

Answer 30

One pouch in males | Two pouches in females

Question 31

What is the name of the male peritoneal pouch?

Answer 31

Rectovesical

Question 32

What are the names of the peritoneal pouches in females?

Answer 32

Uterovesical | Rectouterine (Pouch of Douglas)

Question 33

What is the name for excess fluid in the peritoneal cavity?

Answer 33

Ascitic fluid

Question 34

What is the condition called when a patient has excess fluid in the peritoneal cavity?

Answer 34

Ascites

Question 35

What is the name of the procedure where ascitic fluid is drained from the peritoneal cavity?

Answer 35

Paracentesis

Question 36

Where should the needle be placed during paracentesis?

Answer 36

Lateral to the rectus sheath to avoid the inferior epigastric artery

Question 37

What artery does the epigastric artery arise from?

Answer 37

External iliac

Question 38

Is visceral or somatic pain harder to localise?

Answer 38

Visceral

Question 39

What is the characteristic of visceral pain?

Answer 39

Dull, achy and nauseating

Question 40

What is the characteristic of somatic pain?

Answer 40

Sharp and stabbing

Question 41

What is Colicky pain and what GI problem may it indicate?

Answer 41

Pain that comes in waves, it usually starts and ens suddenly and is often severe (Peristalsis comes in waves so it may indicate a GI obstruction

Question 42

What is the nerve supply to the organs and visceral peritoneum?

Answer 42

``` Visceral afferents (sensory nerves) Enteric nervous system ```

Question 43

What is the effect of the autonomic motor nerve supply of the enteric nervous system?

Answer 43

Parasympathetic - speeds up peristalsis | Sympathetic - slows down peristalsis

Question 44

What is the nerve supply to the skin through to the parietal peritoneum?

Answer 44

Somatic sensory, somatic motor and sympathetic nerve fibres

Question 45

How do sympathetic nerve fibres get from the CNS to the abdominal organs?

Answer 45

Leave the spinal cord between levels T5 and L2 Enter the sympathetic chains but do not synapse Leave the sympathetic chains within abdominopelvic splanchic nerves Synapse at prevertebral ganglia Postsynaptic sympathetic nerve fibres pass from the prevertebral ganglia

Question 46

Where are the prevertebral ganglia located?

Answer 46

Anterior to the aorta at the exit points of the major branches of the abdominal aorta

Question 47

What do the postsynaptic sympathetic nerve fibres pass on the surface of?

Answer 47

Arterial branches leaving the abdominal aorta

Question 48

What do the nerve fibres form around the arteries?

Answer 48

Periarterial plexuses

Question 49

The adrenal gland is unique. Where do the sympathetic nerve fibres for the adrenal gland leave the spinal cord?

Answer 49

T10-L1

Question 50

Where do the fibres supplying the adrenal gland synapse?

Answer 50

Directly onto cell (NOT at prevertebral ganglia)

Question 51

How does the vagus nerve (parasympathetic) get from the CNS to the abdominal organs?

Answer 51

Presynpatic parasympathetic nerve fibres enter abdominal cavity on the surface of the oeosphagus Travel into the periarterial plexuses Carried to organ walls where they synpase in ganglia

Question 52

What does the vagus nerve supply?

Answer 52

Parasympathetic fibres to the GI tract and abdominal organs up to the distal end of the transverse colon

Question 53

What do the pelvic splanchnic nerves (S2, 3 and 4) supply?

Answer 53

Smooth muscle/glands of the descending colon to anal canal

Question 54

Where does pain from the foregut tend to be felt?

Answer 54

Epigastric region

Question 55

Where does pain from the midgut tend to be felt?

Answer 55

Umbilical region

Question 56

Where does pain from the hindgut tend to be felt?

Answer 56

Pubic region

Question 57

Where do most visceral fibres from the abdominal organs to the CNS run?

Answer 57

Alongside sympathetic fibres

Question 58

Where do the visceral afferents from the foregut structures enter the CNS?

Answer 58

T6-T9

Question 59

Where do the visceral afferents from the midgut structures enter the CNS?

Answer 59

T8-T12

Question 60

Where do the visceral afferents from the hindgut structures enter the CNS?

Answer 60

T10-L2

Question 61

Where is organ pain often perceived by a patient?

Answer 61

Dermatomes of the levels at which they enter the spinal cord - referred pain

Question 62

Where is the common site for referred pain for the liver or gallbladder?

Answer 62

Right shoulder

Question 63

Where is the common site for referred pain for the stomach?

Answer 63

Epigastric or between the shoulder blades

Question 64

Where is the common site for referred pain for the gallbladder?

Answer 64

Right side round to right upper back

Question 65

Where is the common site for referred pain for the liver?

Answer 65

Right lower front round to right lower back

Question 66

Where is the common site for referred pain for the small intestine?

Answer 66

Umbilical region

Question 67

Where is the common site for referred pain for the duodenum and pancreas?

Answer 67

Epigastric and mid back (centre, below shoulder blades) | similar to stomach referred pain

Question 68

Where is the common site for referred pain for the spleen?

Answer 68

Left side

Question 69

Where is the common site for referred pain for the kidney and ureter?

Answer 69

Left hip around to left lower back

Question 70

Where is the common site for referred pain for the appendix?

Answer 70

Umbilical and as condition gets worse it moves to the right

Question 71

What are the somatic motor, somatic sensory and sympathetic nerve fibres supply the body wall conveyed within?

Answer 71

Thoracoabdominal nerves, subcostal nerve, iliohypogastric nerve and ilioinguinal nerve

Question 72

What specific thoracoabdominal nerves?

Answer 72

7th - 11th intercostal nerves

Question 73

What leel is the subcostal nerve?

Answer 73

T12 anterior ramus

Question 74

What part of the iliohypogastric nerve?

Answer 74

Half of L1 anterior ramus

Question 75

What part of ilioinguinal nerve?

Answer 75

Other half of L1 anterior ramus

Question 76

Why does the pain from appendicitis start as a dull, aching pain but become a sharper pain at a point?

Answer 76

It is a midgut organ - pain tends to be felt in the umbilical region (visceral afferents T8-T10) As appendicitis worsens it starts to irritate the peritoneum in the right iliac fossa - becomes a somatic pain