Thoracic Neurology Flashcards
What does the esophagus connect?
laryngopharynx
stomach
Describe the two muscular layers of the esophagus.
inner circular layer
outer longitudinal layer
True or False:
the upper 2/3rds of the esophagus is smooth muscle and skeletal muscle
What are the four constriction points of the esophagus?
- cricopharyngeus M.
- near the aortic arch
- near the left bronchus
- at the esophageal hiatus
Where in the thorax is the phrenic N.?
-between the mediastinal parietal pleura and the fibrous pericardium of the heart
What does the phrenic N. innervate?
thoracic diaphragm
-conveys sensory info from the pericardium, central diaphragmatic parietal pleura, and mediastinal parietal pleura
What are the branches of the vagus N.?
- superior, middle, and inferior cardiac branches
- recurrent laryngeal N.
- pulmonary branch
- esophageal branch
- becomes vagal trunks
What does the right vagus N. become?
posterior vagal trunk
What does the left vagus N. become?
anterior vagal trunk
What do the cardiac branches of the vagus N. innervate?
heart
What do the recurrent laryngeal nn. innervate?
lateral and posterior cricoarytenoid mm. transverse arytenoid M. oblique arytenoid M. thyroarytenoid M. vocalis M.
Under what structure(s) does the right laryngeal N. loop?
right subclavian artery
Under what structure(s) does the left recurrent laryngeal A. loop?
aortic arch
ligamentum arteriosum
What does the pulmonary branch of the vagus N. innervate?
lungs
bronchi
pleura
Through what opening does the vagus N. pass as it leaves the thorax?
esophageal hiatus
What are the intercostal nn.?
anterior rami of the thoracic spinal nerves
Where are the intercostal nn. located?
in the costal groove on the inferior surface of the rib
b/w the internal intercostal M. and the innermost intercostal M.
What do the intercostal nn. innervate?
skin
subcutaneous tissue
musculature
costal and diaphragmatic parietal pleura
What connects the intercostal nn. to the thoracic sympathetic trunk?
rami communicantes
Where are the collateral branches of the intercostal nn.?
on the superior edge of the rib below
What do the intercostal nn. branch into?
lateral cutaneous branches
–become anterior and posterior branches
What do the anterior and posterior branches of the lateral cutaneous branch of the intercostal nn. innervate?
-skin of the thoracic wall
What nerves supply the breast?
-anterior branches of the lateral cutaneous branches of intercostal nn. of T4-T6
What do the muscular branches of the intercostal nn. supply?
external intercostal M. internal intercostal M. innermost intercostal M. subcostal M. transverse thoracis M.
What is unique about the first intercostal N.?
- no cutaneous branches
- majority of the superior portion joins the brachial plexus
What is unique about the second intercostal N.?
- small part joins the brachial plexus
- lateral cutaneous branch innervates the skin and subcutaneous tissue of the axilla
What is unique about the 7th-11th intercostal nn.?
-become thoracoabdominal nn. as they transition anteriorly over the abdomen
What is the “motto” of the parasympathetic nervous system?
rest and digest
What thoracic structures have parasympathetic innervation by the vagus N.
- lungs
- bronchi
- pleura
- heart
- pericardium
What structures are linked along the thoracic sympathetic trunk?
paravertebral ganglia
Are cardiopulmonary splanchnic nerves presynaptic or postsynaptic?
postsynaptic
Where are the cell bodes of the cardiopulmonary splanchnic nerves?
lateral horn of the spinal cord
T1-T5
What is the “motto” of the sympathetic nervous system?
“fight or flight”
Are abdominopelvic splanchnic nerves presynaptic or postsynaptic?
presynaptic
Where do the fibers of the abdominopelvic splanchnic nerves synapse?
prevertebral ganglia in abdominal organs
What are the abdominopelvic splanchnic nerves and their thoracic spinal nerve levels?
- greater splanchnic N. (T5-T9)
- lesser splanchnic N. (T10-T11)
- least splanchnic N. (T12)
What does the greater splanchnic N. innervate?
- esophageal plexus
- celiac plexus (liver, gall bladder, stomach, pancreas, spleen)
What does the lesser splanchnic N. innervate?
- celiac ganglion
- superior mesenteric ganglion
-intestines, rectum, anal sphincter
What does the least splanchnic N. innervate?
- aorticorenal ganglion
- kidneys and adrenal glands
What supplies parasympathetic innervation to the pulmonary plexus?
-pulmonary branch of vagus N.
What are the parasympathetic functions of the pulmonary branch of vagus N.?
- bronchoconstrictor
- pulmonary vessel vasodilation
- cough reflex
- pressure sense from pulmonary A.
- chemoreceptor from pulmonary V.
What supplies the sympathetic innervation to the pulmonary plexus?
pulmonary splanchnic N.
T2-T3
What are the sympathetic functions of the pulmonary splanchnic N.?
- bronchodilator
- inhibition of bronchi/bronchiole glands
- pulmonary vessel vasoconstriction
- visceral sense from lungs, bronchi, and pleura
What is the parasympathetic innervation of the cardiac plexus?
-superior, middle, and inferior cardiac branches of the vagus N.
What are the parasympathetic functions of the cardiac branches of the vagus N.?
- decrease heart rate
- reduce force of heart ctx
- vasoconstriction of coronary aa.
What is the sympathetic innervation of the cardiac plexus?
-cardiac splanchnic N.
T1-T5
What are the sympathetic functions of the cardiac splanchnic N.?
- increase heart rate
- increase force of heart ctx
- vasomotor to pericardium
What does the superficial cardiac plexus innervate?
anterior surface of the aorta
What provides parasympathetic innervation to the esophageal plexus?
esophageal branches of the vagus N.
What are the parasympathetic functions of the esophageal branches of the vagus N.?
- stimulates peristalsis
- stimulates esophageal glands
What provides the sympathetic innervation of the esophageal plexus?
greater splanchnic N.
T5-T9
What are sympathetic functions of the greater splanchnic N. in regards to the esophagus?
- inhibits peristalsis
- inhibits esophageal glands
