Abdominal Pain Flashcards
What is the difference between somatic and visceral abdominal pain?
- pain pathways and neurones
- pain characteristics
- stimuli
Somatic
- pain from abdominal wall via the peripheral cutaneous nerves. Adelta fibres (myelinated)= initial sharp pain, C fibres (non-mylelinated) = longer diffuse pain
- pain is localised, sharp, contact,
- stimuli are pressure, incisions, temperature
Visceral
- pain from abdominal organs = sympathetics
pain from pelvic organs = parasympathetics
- pain is diffuse, dull, colicky
- stimuli are distension, traction, ischaemia
Where is pain from cholecystitis felt and why?
Inflammation of the gallbladder
RUQ
Neck - irritates diaphragm which originates from cervical sorties in the neck
Explain reffered pain with regards to a myocardial infarction.
pain is felt in neck, chest, shoulder and arm
pain fibres from the heart travel with the sympathetic supply to the heart and converge upon spinal segment T1-T4
T1-T4 dermatomes include the neck, upper chest and inner arm
Thus the CNS interprets this pain as originating from T1-T4 dermatome regions
What is the autonomic innervation of the foregut, midgut, hindgut and pelvic organs?
foregut = greater splanchnic
midgut = lesser splanchnic
hindgut = least splanchnic
pelvic organs = pelvic parasympathetic
From which organs will pain be felt in the midline? Why?
From which organs will pain not be felt in the midline?
Aorta, All GIT, pancreas, GB and liver = originate as midline strucutres
Testicle, kidneys = did not originate as midline structures
Why is visceral pain poorly localised/
Because the pain fibres spread of several spinal segments
What determines whether pain is felt in the front or back?
Give examples
- All gut pain and gut structures are felt anteriorly
- Retroperitoneal structures are felt in the back = kidneys, ureters, pancreas, retroperitoneum, aorta, lower part of rectum, 2nd-4th part duodenum
- Pain fibres travelling with parasympathetics are felt in the back e.g. oesophagus, uterus, ovaries, fallopian tubes
Why is pain due to obstruction or increased activity of bowel collicky in nature?
spasm of smooth muscle
Describe the pattern of pain from appendicitis?
Orginates as visceral pain in the umbilical region. It is a midgut structure that originated in the midline. Pain is diffuse, collicky and poorly localised because the lesser splanchnic nerve spreads over several spinal segments.
Once progressed the appendix can start to irritate the paritetal peritoneum. This has somatic innervation so the pain will localised to the right iliac fossa and because intense and stabbing in nature and is constant
A patient with abdominal pain comes in and is lying completly still, curled in a fetal position and is vomitting. What are the 2 possible causes?
How would you differentiate between the two on XRAY and with bowel sounds
vomiting may be reflex due to parasympathetic stimulation or due to obstruction
Obstruction - distenstion, bowel loops on XR, high pitched bowel sounds
Describe the classic pain patterns of renal colic
location - groin, lateral structure,retoperitoneal
pattern - colic, intense,
Describe the classic pain pattern of pyelonephritis
location - loin
pattern - constant
Describe the classic pain pattern of biliary colic
epigastric
ache
fatty meal
Describe the classic pain pattern of cholecystitis
RUG and R shoulder
constant, lasts days
Murphy positive
Describe the classic pain pattern of pancreatitis
epigastrium and back
constant
