Thorax 4 Flashcards
label what u can
Right recurrent laryngeal nerve
The right vagus nerve gives rise to the right recurrent laryngeal nerve, which hooks around the right subclavian artery and ascends into the neck between the trachea and oesophagus
Travels along the tracheo-osophageal groove
Left vagus relation to arteries
Right vagus relation to arteries
Runs between common carotid artery and subclavian
Runs alongside right carotid artery
Cardiac branches of vagal nerve
these innervate regulate heart rate and provide visceral sensation to the organ
from left
Left recurrent laryngeal nerve
Left recurrent laryngeal nerve – it hooks under the arch of the aorta behind the ligamentum arteriosum, ascending to innervate the majority of the intrinsic muscles of the larynx
After the ligamentum arteriosum, the left recurrent laryngeal nerve runs inferiorly round the aorta and travels superiorly into the lower neck towards the larynx
Anterior and posterior vagal trunk
In the thorax, the Vagus nerves form:
- Right – posterior vagal trunk
- Left – anterior vagal trunk
=
LARP - part of carotid sheath
Branches from the vagal trunks contribute to the formation of the oesophageal plexus, which innervates the smooth muscle of the oesophagus
Also contribute to pulmonary plexus
Path of the phrenic nerve: relation to vagus, BCV and clavicle
where does phrenic nerve originate from?
Enters the superior mediastinum lateral to vagus nerve and behind the brachiocephalic veins
Passes anteriorly to the hilum of the lung and over the pericardium of the heart sending small pericardial branches to it
Crosses vagus at arch of aorta
2x phrenic nerve is on lateral side of heart and medial side of lungs
cervical plexus 3,4,5
label and what is its function
cardiac skeleton
Helps maintain integrity of openings and provides attachments for cusps
Separates muscular wall of atria from ventricles, as well as electrically isolating the ventricles
Name the papillary muscles in the RV
Named relative to their point of origin
Anterior: largest
Posterior: may consist of 1-3 structures
Septal: inconsistent (small or absent) - sometimes the chordinae tendinae attach to the trabeculae carnae instead of the septal if it is absent
what is the Septomarginal trabecula
where is the septomarginal trabelcullae (moderator band)?
Septomarginal trabecula: bridge between the interventricular septum and the base of the anterior papillary muscles
-Carries a portion of the cardiac conduction system to the anterior wall of the RV to make sure contraction is coordinated
interventricular septum
how many papillary msucle does the bicuspid (mitral) valve have? LA –> LV
only 2 - anterior and posterior paillary muscles
How do the cusps of the semilunar valves attach?
Via the cartilaginous ring
Ligamentum arteriosum
A band of fibrous tissue connecting the top of the pulmonary bifurcation to the bottom of the aortic arch - it is the remains of the ductus arteriosum, an artery present before birth which diverts blood from the lungs before a baby starts to breathe
Give the branches of the aortic arch
Where is the beginning of the descending thoracic aorta?
how does the descending thoracic aorta pass?
T4-T5
Posterior mediastinum
posterior to left main bronchus
left of oesophagus
behind diaphragm - enters it at T12
how many branches of each bronchus?
right branches into two primary - 2 seen in the hillum
left branches into one primary
supply of blood to intercostal spaces?
The first and second posterior intercostal arteries originate from the superior (supreme) intercostal artery, a branch of the costocervical trunk
Third to eleventh posterior intercostal arteries arise directly from the posterior surface of the thoracic aorta.
the internal thoracic artery gives off:
The upper six anterior intercostal arteries
Musculophrenic arteries, which give off the 7th to 9th intercostal arteries
what is in the carotid sheath?
internal jugular vein
common carotid artery
vagus nerve
2 tributaries of braciocephallic vein made?
from internal jugular vein and subclavian vein
borders of vertebral foramen?
lamina (posteriorly)
pedicle (sides)
what do eth illaic veins become continuous with?
the IVC
Accessory HA drains into azygous at what level?
vs proper/ inferior
t7
t8
Anterior thoracic wall lymph drainage
Posterior thoracic wall lymph drainage
Parasternal and diaphragmatic nodes and intercostal are posterior
where does Thoracic duct start
where does the thoracic duct pass?
where does the thoracic duct enter?
Starts at cisterna chyli (a dilated sac at lower end of thoracic duct)
Passes through aortic hiatus, behind the oesophagus and behind aortic arch to superior neck root
enters the left braciocephalic vein
lymph drainage of thorax
Right lymphatic duct is responsible for drainage of the upper right quadrant of the body
the rest 75% is by thoracic duct
somatic vs autonomic NS?
somatic = voluntary
autonomic = involuntary and either symp or parasymp or enteric for GI tract
label the lateral horn and give its function
The lateral horn of the spinal cord is the small lateral projection of grey matter located between the dorsal horn and ventral horn and contain the neuronal cell bodies of the sympathetic nervous system
Function of preganglionic fibres symp
Preganglionic fibres are short and synapse with roughly 30 postganglionic neurons
Facilitates divergence and more widespread response
The lower 8 ganglia mainly give pre-ganglionic fibres, which are grouped together to form
thoracic splanchnic nerves and supply abdominal viscera.
How do they enter the abdominal cavity?
Through diaphragm
- T5-T9 form the greater splanchnic nerve (to foregut)
- T10-T11 form the lesser splanchnic nerve (to midgut)
- T12 forms the least splanchnic nerve (to kidneys and upper ureter)
- L1-L2 form lumbar splanchnic nerves (to hindgut)
