Flashcards in CPR Thoracic Neurology Deck (56)
What is the role of the esophagus?
What is it composed of?
joins the laryngopharynx to the stomach
2 layer muscle tube (internal circular layer & external longitudinal layer)
Where is the esophagus located in the thorax?
between T1 & esophageal hiatus
travels thru posterior mediastinum
Name the constrictors of the esophagus
@ cricopharyngeus m (upper esophageal sphincter)
@ aortic arch
@ left bronchus
@ esophageal hiatus of thoracic diaphragm (lower esophageal sphincter)
Which CN is associated w/ thorax?
Where does it enter?
vagus N (R & L)
enters thru superior thoracic aperture
What are the branches of the vagus N in the thorax?
L recurrent laryngeal N
sup/middle/inferior cardiac branches
anterior vagal trunk
posterior vagal trunk
Anterior v Posterior vagal trunks
anterior from L vagus N
posterior from R vagus N
What cervical spinal N is assoc w/ the thorax?
phrenic N (anterior rami of C3-5)
Where does the phrenic N travel?
thru superior thoracic aperature into space btwn mediastinal parietal pleura & fibrous pericardium
What does the phrenic N innervate?
What do the intercostal Ns innervate?
skin, subcutaneous tissue, muscles, and costal & diaphragmatic parietal pleura
What composes the intercostal Ns?
Where do they run?
anterior rami of thoracic spinal Ns
along inf edge of superior rib in the intercostal space btwn internal & innermost intercostal ms
What are the typical intercostal Ns?
3rd-6th intercostal Ns
Which intercostal Ns supply the breast?
lateral cutaneous branches & anterior cutaneous branches of T4-T6
What do the collateral branches of intercostal Ns 3-6 innervate?
Where do the collateral branches travel?
innervate intercostal ms
along sup edge of rib inf to intercostal space
What do the muscular branches of intercostal Ns 3-6 innervate?
transversus thoracic m
What are the atypical intercostal Ns?
1st & 2nd, 7th-11th
What do the rami communicates of intercostal Ns 3-6 do?
connected intercostal N to ipsilateral sympathetic trunk
What makes the 1st intercostal N atypical?
no cutaneous branches & majority superior portion joins brachial plexus
What makes the 2nd intercostal N atypical?
majority travels in costal groove w/ small part joining w/ brachial plexus
lateral cutaneous branch supplies skin/tissue of axilla (intercostobrachial N)
Where does the intercostobrachial N originate?
2nd intercostal N
What makes the 7th-11th intercostal Ns atypical?
travel anteriorly & no longer exist btwn ribs
transition over abdomen to become thoracoadominal N
What are the general principles of the autonomic nervous system (ANS)?
sympathetic stimulation is catabolic (fight or flight)
parasympathetic stimulation is anabolic (normal function & energy conservation)
parasympathetic is only in head/neck & trunk viscera while sympathetic distributes to every vascular area of body
parasympathetic controls gland secretion (except sweat glands)
sympathetic can indirectly decrease non-sweat gland secretion via vasoconstriction
vasoconstriction is sympathetically stimulation (except of coronary As)
Where does sympathetic division of ANS arise from?
presynaptic fibers have cell bodies in lateral horn of spinal cord from T1-L2
Presynaptic fibers of sympathetic
cells bodies in lateral horn of SC
always travel in anterior root
always travel into anterior ramus
quickly exit anterior ramus & enter paravertebral ganglia
What are the 3 synaptic options for sympathetic presynaptic fibers?
synapse @ paravertebral ganglion of same SC level
ascend/descend to synapse @ paravertebral ganglion of different SC level
exit paravertebral ganglion w/o synapsing & continue with abdominopelvic splanchnic nerve to a postsynaptic neuron in PREvertebral ganglion
Describe the paravertebral ganglia
contain postsynaptic cell bodies
linked vertically to form sympathetic trunks
3 ganglia exist in cervical, lumbar & pelvic regions
Describe the prevertebral ganglia
contain postsynaptic cell bodies
ganglia & corresponding plexuses surrounding the main unpaired branches of abdominal aorta
What are the 4 prevertebral ganglia?
superior mesenteric ganglion
inferior mesenteric ganglion
Describe the sympathetic presence in the thorax
thoracic sympathetic trunk
cardiopulmonary splanchnic Ns
abdominopelvic splanchnic Ns