Abdominal Pain Flashcards
organs of foregut
oesophagus to mid-duodenum liver gallbladder spleen half of pancreas
organs of midgut
mid-duodenum to proximal 2/3rd of transverse colon
half of pancreas
organs of hindgut
distal 1/3 of transverse colon to proximal half of anal canal
arterial supply of abdominal organs
common artery
venous supply of abdominal organs
common vein
lymphatic drainage of abdominal organs
via shared route
nerve supply of abdominal organs
(includes the visceral peritoneum) visceral afferents ANS - influences ENS; parasympathetic sympathetic
regions of abdominal cavity
9 intotal
divided along mid-clavicular, subcostal and trans-tubercular planes
name the 9 regions of abdominal cavity
right/left hypochondrium epigastric right/left lumbar umbilical right/left inguinal pubic
quadrants of abdominal cavity
4 in total
divided along median and trans-umbilical planes
name the 4 quadrants of abdominal cavity
right/left upper quadrant
right/left lower quadrant
describe the membrane of peritoneal cavity
peritoneum - thin, transparent, semi-permeable, serous membrane
sensitive
secretes lubricating fluid
what does the peritoneum line
continuous layer of membrane lining the walls of abdominopelvic cavity and organs - creating peritoneal cavity between visceral and parietal layers
intraperitoneal organs
organs covered in visceral peritoneum
minimally mobile
retroperitoneal organs
organs have visceral peritoneum on its anterior surface
located in retoperitoneum
organs with a mesentery
organs covered in visceral periotneum
visceral peritoneum wraps behind the organ to form a double layer - the mesentery
mesentery suspends the organ from the posterior abdominal wall - very mobile
example of an intraperitoneal organ
liver
example of retroperitoneal organs
pancreas
kidneys
examples of organs with a mesentery
parts of intestines
condensations of peritoneum
double layers
attaches organs to each other or to the abdominal wall
secondary to growth and rotation of GI tract during embryology
examples of condensations of periotneum
falciform ligament
greater omenetum
lesser omentum
describe the omenta
divides the peritoneal cavity into greater sac and lesser sac
communication between greater and lesser omenta
via the omental foramen
where does the portal triad lie
in the free edge of the lesser omentum
pouches of peritoneum
at its inferior aspect, the peritoneum drapes over the superior aspect of the pelvic organs - forming pouches (part of the greater sac)
what is ascites
when excess fluid collects within the peritoneal cavity (pathological)
how is ascites treated
drained via paracentesis
describe process of paracentesis
needle placed lateral to rectus sheath - avoiding the inferior epigastric artery
where does the inferior epigastric artery arise
from the external iliac artery
nerve supply of the abdominal body wall
(includes the parietal periotenum)
somatic sensory nerves
somatic motor nerves
sympahtetic nerve fibres
where do the sympathetic nerve fibres leave the spinal cord to get to the abdominal organs
T5 and L2 to enter the sympathetic chains (bilaterally)
do not synapse
where do the sympathetic nerve fibres leave the sympathetic chains to get to the abdominal organs
leave within abdominopelvic splanchnic nerves
where do the sympathetic nerve fibres synapse to get to the abdominal organs
at the prevertebral ganglia
where are the prevertebral ganglia located
anterior to the aorta at the exit points of the major branches of the abdominal aorta
describe the course of the postsynaptic sympathetic nerve fibres
pass from the prevertebral ganglia onto the surface of the arterial branches leaving the abdominal aorta
what is meant by periarterial plexuses
nerve fibres (including the postsynaptic sympathetic nerve fibres) hitch a ride with the arteries and their branches towards (or away) the smooth muscle and glands of the organs
course of sympathetic nerves to abdominal organs - adrenal gland
leave spinal cord at T10-L1 and enter abdominoplevic splanchnic nerves - do not synapse
carried with periarterial plexuses to adrenal gland - synapse directly into cells
course of parasympathetic nerves to abdominal organs - vagus nerve
presynaptic parasympathetic nerve fibres enter abdominal cavity on surface of oesophagus
travel into periarterial plexuses around abdominal aorta
carried to walls of organs - synapse in ganglia
what do presynaptic nerve fibres supply
supply parasympathetic nerve fibres to the GI tract and abdominal organs up to distal end of transverse colon
course of parasympathetic nerves to abdominal organs - pelvic splanchnic nerves
presynaptic nerve fibres supply the smooth muscle/glands of the descending colon to anal canal
where is pain the foregut felt
epigastric region
where is pain the midgut felt
umbilical region
where is pain the hindgut felt
pubic region
course of visceral afferents from abdominal organs to CNS
pain fibres from vast majority of abdominal organs run alongside sympathetic fibres back to spinal cord
where do pain fibres from foregut structures enter the spinal cord
T6-T9
where do pain fibres from midgut structures enter the spinal cord
T8-T12
where do pain fibres from hindgut structures enter the spinal cord
T10-L2
what is meant by referred pain
pain from abdominal organs perceived in the dermatomes of the levels at which they enter the spinal cord
nerves supplying the body wall
somatic motor
somatic sensory
sympathetic nerve fibres
where are body wall nerves conveyed within
the thoracoabdominal nerves subcostal nerves (T12) iliohypogastric nerve (L1) ilioinguinal nerve (L1)
course of the thoracoabdominal nerves
7-11th intercostal nerves
Travel anteriorly, leave the intercostal spaces, travel in the plane between the internal oblique and transversus abdominis, as thoracoabdominal nerves
