1-Differential Diagnosis of Chest pain Flashcards
what is an example of visceral reflex afferent pathway?
visceral reflex afferent pathway = reflex sensory nerves from organs
example = baroreceptors are sensory receptors that detect changes in blood pressure. The afferent (sensory) fibers from baroreceptors (which are part of visceral reflex system) predominantly travel in vagus nerve
what is visceral afferent innervation and
a) how do pain fibers travel?
b) how do visceral reflex afferents travel?
= sensory nerves travelling from organs.mostly similar route - travel through autonomic nerves, enter spinal cord at dorsal roots
a) pain fibres from visceral organs can travel to spinal cord alongside both sympathetic & parasympathetic nerves (so pain fibres travel same pathway as sympathetic & parasympathetic nerves to spinal cord)
b) visceral reflex afferents = sensory nerves responsible for reflex activities in response to changing condition, mostly travel in vagus nerve but some also travel in accessory nerve (CN XI)
what sympathetic neurotransmitter is released at ganglion synapse of
a) presynaptic neuron and post synaptic neuron?
b) post synaptic fibre connecting ganglion & organ?
a) acetylcholine
b) noradrenaline
what parasympathetic neurotransmitter is released at ganglion synapse of
a) presynaptic neuron and post synaptic neuron?
b) post synaptic fibre connecting ganglion & organ?
a) acetylcholine
b) acetylcholine
where do presynaptic sympathetic fibres exit?
they travel inferiorly in spinal tract & exit from T1-L2 = thoracolumbar outflow
what are the 5 options of what sympathetic nerves do once exit spinal cord?
*for sympathetic innervation of heart - only 1st 3 relevant
- into ganglion and synapses at same level it exited
- can travel superiorly through sympathetic chain and synapse higher up
- travel inferiorly and synapse at lower ganglion
- pass straight through sympathetic chain ganglion without synapsing, as abdominopelvic splanchnic nerves to synapse in one of prevertebral ganglia of abdomen e.g. celiac ganglion
- pass straight to adrenal medulla without synapsing as an abdominal pelvic splanchnic nerve
what are splanchnic nerves?
= preganglionic neurons that don’t synapse at sympathetic ganglia but travel to organs etc
- preganglionic nerve fibers exit spinal cord and travel to sympathetic chain ganglia
- when reaching sympathetic chain ganglia, some synapse with post ganglionic neurons in ganglion
- however some nerves don’t synapse and become splanchnic nerves composed of preganglionic neurons and travel as bundles of nerves outside sympathetic chain
what are some types of splanchnic nerves?
- abdominopelvic splanchnic nerves
- cardiopulmonary splanchnic nerves
what is cardiac plexus and what is it made up of?
plexus = intertwining of nerves
made up of:
1. sympathetic fibres
2. parasympathetic fibres
3. visceral afferent fibres
what are cardiopulmonary splanchnic nerves?
they are post synaptic fibres from cervical & upper thoracic sympathetic chains
how do parasympathetic signals reach organs - where do they exit?
craniosacral outflow:
cranial nerves: (from head)
- CN III = oculomotor
- CN VII = facial
- CN IX = glossopharyngeal
cranial nerve CN X = vagus nerve (from chest & upper abdomen)
sacral level of spinal cord = to organs of the lower abdomen, pelvis & perineum
what splanchnic nerves are parasympathetic?
pelvic splanchnic nerves
what is route of presynaptic parasympathetic fibres?
- they travel in vagus nerve
- when they approach chest & upper abdomen organs they branch into smaller nerve fibres
- in ganglia (that are on target organs wall), they synapse and are then called post-synaptic neurons
- these post synaptic neurons within the ganglia have short axons that extend to nearby tissues and allow signals etc
what is outflow of
a) sympathetic?
b) parasympathetic?
a) thoracolumbar
b) craniosacral
what does somatic pain feel like?
body wall = sharp, stabbing, well localised
what does visceral pain feel like?
organ =dull, achy, nauseating, hard to place exactly where pain comes from
what are examples of places causing somatic pain?
- muscular
- joint
- bony
- intervertebral disc
- fibrous pericardium
- nerve
what are examples of places causing visceral pain?
- heart & great vessels
- trachea
- oesophagus
- abdominal viscerae
what is radiating pain?
pain felt in centre of chest and felt spreading from there e.g. to upper limbs, back, neck
what is referred pain?
pain ONLY felt at site remote from area of tissue damage in chest e.g. upper limbs, back, neck