The Cardiovascular and Respiratory System Flashcards
(99 cards)
1
Q
Where is the thorax located?
A
The thorax is located between the neck (above) and the abdomen (below)
2
Q
How many parts does the thorax have?
A
The thorax has two parts, the chest walls and the chest cavity.
3
Q
What does the chest wall refer to?
A
It refers to anything that surrounds the chest cavity.
4
Q
What is part of the chest wall?
A
The skeletal structures. So the midline breastbone, the ribs and posteriorly:
The thoracic vertebral column and also parts of the scapulae (shoulder blades)
In addition to skeletal structures, there are also muscles, tendons, ligaments. Soft tissues such as fat, which is known as fascia, superficial fascia and the overlying skin, so the soft tissues combined with the hard tissues are forming the chest wall.
5
Q
What is the function of the chest wall:
A
Protect the heart and lungs - The soft and hard tissue
Make the movements of breathing - The joints and muscles
Breast tissue - lactation (lactare = to suckle)
6
Q
What is the chest cavity?
A
It is the part of the thorax, within the chest walls and contains the visceral structures.
7
Q
What does viscera mean?
A
Viscera means organ, any organ is referred to as a visceral structure.
8
Q
What does the chest cavity contain?
A
Contains vital organs (also known as viscera)
Also contains major vessels and nerves
9
Q
What are the largest visceral structures in the chest cavity?
A
The lungs and heart are the largest visceral structures in the chest walls
10
Q
What are the skeletal structures/bones in the thorax?
A
There are 12 thoracic vertebraes from T1-T12
With each thoracic vertrebrae, there is an associated right and left rib.
Alongside this is the collarbone (clavicle)
And the shoulder blade, known as the scapula
11
Q
How many total vertebrae are there in the adult vertebrae column?
A
There are 33 total vertebrae in the adult vertebral column.
12
Q
What are the vertebrae of the adult vertebrae column?
A
There are 33 Vertebrae:
7 Cervical (C1-C7)
12 Thoracic
5 Lumber (L1-L5)
5 Sacral (Fused to form 1 Sacrum)
4 Coccygeal (Fused to form 1 coccyx).
13
Q
What shape does the column have when viewed from the side?
A
The column has an ‘S’ shape when viewed from the side, composed of primary curvatures, with an anterior cavity.
There also is secondary curves in the neck, lumbar and cervical region.
14
Q
What are the parts of the Thoracic Vertebra?
A
A thoracic vertebra can be divided into two parts.
A front body known as a vertebral body and the vertebral arch.
It also contains several ‘processes’:
15
Q
What is the function of the front body/vertebral body?
A
the front body is about transmitting weight (weight distribution).
16
Q
What does the vertebral arch contain and what is the function of the vertebral arch?
A
The vertebral arch has a pedicle, which connects the vertebral body to the arch, it is a connecting bar bone, and also a Lamina, which connects the processes to the arch.
17
Q
What processes are contained in the thoracic vertebra
A
Transverse process, Spinous process, Inferior and superior articular processes.
18
Q
What is the function of the transverse process?
A
it is located in the transverse plane and involved in ligament muscle attachment and rib articulations.
19
Q
What is the function of the spinous process
A
The spinous process is involved in ligament and muscle attachment
20
Q
What is the function of the Inferior and superior articular processes?
A
It is involved in the articulation for the vertebrae that sits above and the vertebrae that sits below.
21
Q
How many pairs of ribs are there?
A
There are twelve pairs of ribs, for every pair of rib there is a thoracic vertebrae.
22
Q
What can ribs be classified as?
A
Ribs can be classified as being typical or atypical.
23
Q
What are the characteristics of typical ribs?
A
Typical ribs have typical features - they tend to look the same and have the same anatomical features.
Typical ribs
- have a head with 2 facets (articulations)
- A tubercle, which is a lump/bump of bone with a articulating facet (grey areas show articulating points)
- Between head and tubercle is a short neck
- Shaft or body that extends all the way anteriorly
- At the anterior end of the rib, the rib will articulate with the sternum via the costal cartillage or the costal margin.
- Round the shaft, there is a lateral element known as the angle of the rib, where the rib changes direction.
- A cross section of the rib shows a costal groove contains a neurovascular bundle
- a neurovascular bundle is a bundle of tissues that contains an artery, a nerve, and a vein.
- In line, sitting within the costal groove, we would have a nerve, an artery in a vein.
24
Q
What the characteristics of atypical rib 1?
A
- Very short and broad, with a sharp curve
- Least likely to fracture due to its short, broad morphology.
- Tucked right next to clavicle to very protected and very unlikely to fracture.
- Superior surface of rib one contains a scalene tubercle between two channelled out grooves.
- the scalene tubercle marks the point of which one of the neck muscles called a scalenus anterior muscle attaches to rib one.
- The bump formed results from the muscle being attached at the scaling tubercle
- The bump is called the scarring typical
- on either side of the scalene tubercle we have a groove caused by vessels
- The grove anterior to the scalene tubercle is for the subclavian vein
- The groove behind, posterior to the scalene tubercle is for the subclavian artery.
Rib 1 also has a shaft/body, a small tubercle, a neck and a head with only 1 facet.
25
How would the ribs join with the chest wall?
The head with two facets are able to articulate with two thoracic vertebraes.
As a general rule, a numbered rib will articulate with the thoracic vertebrae of the same number and the thoracic vertebrae located above.
For example, for rib two it would articulate at the head with T1 and T2.
26
What does the tubercle off the rib articulate with?
Tubercle off the rib articulates with the transverse process of the thoracic vertebrae
These joints between the ribs and articulator facets on the vertebraes are collectively called costovertebral joints.
27
What are costovertebral joints?
Costovertebral joints are:
- Synovial cavities important in movement during breathing.
And are a joint between the rib and the vertebrae, therefore across two vertebral joint.
28
What are the characteristics of the sternum?
- Located anteriorly in the midline.
- Composed of three parts,
- Superior part known as manubrium
- The main part known as the body or the mesial sternum.
- The bottom which has the xiphoid process
- There are several number of joints
- Sternal costal joints - joints between the costal cartilage of rib and the sternum itself.
- Costolchondral joints - junctions between the ribs and the costal cartilage.
- Very limited movement at these joints
Has a large costal cartilage known as the costal margin
29
What are the three parts of the sternum?
There is the:
Manubrium
Body
Xiphoid Process
30
What exists along the side of the sternum?
Along the side of the sternum, there exists costal notches that exist for articulation with the costal cartilage and costal margin.
These are where the costal cartilage articulate with the sternum.
31
What is the sternal angle?
Between the manubrium and the main body of the sternum there is angulation.
This is called the sternal angle, it is always located at the position of rib 2.
This is a useful pointer for when determining rib locations.
32
What is the sternalclavicular joint?
The sternalclavicular joint between the sternum and the clavicle.
33
What is prominent just below the skin?
The clavicle is prominent just below the skin.
34
What is between the clavicle?
Between the clavicles is the jugular notch, it is located at the superior boundary of the manubrium, which is the top part of the sternum.
35
What does pushing deep at the jugular notch enable you to palpate?
Pushing deep at the jugular notch enables you to palpate the trachea
36
What is below the jugular notch?
Below that is the midline sternum, which should be able to be palpated (felt) quite clearly.
If felt carefully, the sternal angle can be palpated.
If the sternal angle is found, and is laterally palpated from there, we are able to find the location of rib two, which is located at the level of the sternal angle.
There is also the pectoralis major muscles, (peps are clearly visual.)
37
What is below the pectoralis major muscles?
Below the pectoralis major muscles is the xiphoid process which is the terminal part of the sternum, palpating the costal margin is also possible.
38
What are the various underlying layers of anatomy through the anterolateral chest wall?
First layer – skin
Second layer = fat or adipose tissue known as superficial fascia (Can be of varying thickness dependant on individual being dissected.)
Third layer – deep fascia, a thick fat layer which is a fibrous, tough connective tissue layer but thinner than the superficial fascia that directly overlies on the muscle.
Fourth Layer – the first muscle under the deep fascia is the pectoralis major. Superior to it would be the anterior part of the deltoid muscle. They are both attached to the clavicle and have a groove between them known as the delta pectoral groove
39
What does the delta pectoral groove contain?
In the groove there is a vein that drains the upper limb and is known as the cephalic limb that takes the venous blood from the upper limb and taking it to the veins in the neck.
40
What sensory nerves are part of the underlying anatomy of the anterolateral chest wall and what do they do?
The sensory nerves also known as intercostal nerves, supply the muscles of the chest wall.
41
What does the serratus anterior do, what are it's characteristics?
- functions to anchor the scapula to the ribs as the scapula lacks any bony articulations or joints that anchor it to the thoracic wall
- It's nerve supply lines are on the superficial surface of the muscle
- This can be dangerous as during some medical procedures, for example, a mastectomy where a female has breast tissue or the breast removed,the surgeon can accidentally nick that long thoracic nerve, and that could result in paralysis of the serratus anterior muscle group because it would no longer be innervated by it's nerve.
- Damaged long thoracic nerves can result in a condition called wing scapula. This is when the scapula is no longer anchored onto the thoracic cage due to the nerve damage and so it sticks out.
42
What is posterior to the serratus anterior?
Posterior to the Serratus Anterior is a muscle that's called the latissimus dorsi
43
Where is the serratus anterior located?
It is located between the ribs and the scapula, at the lateral part of the chest wall.
44
What is the fifth layer/below the Pectoralis major muscle?
The Pectoralis Minor muscle which extends from the scapula down onto the ribs and is sitting deep to the pectoralis major muscle.
45
What are the characteristics of intercostal muscles?
Intercostal Muscles:
- They sit between each pair of ribs.
- They consist of three layers, three muscles:
- There is the external intercostal muscle
- the internal intercostal muscle
- the innermost intercostal muscle.
These intercostal muscles pull the ribs together and cause movements of the chest wall during breathing.
46
What exists between internal and innermost intercostal muscle layers?
Between internal and innermost intercostal muscle layers, in each intercostal space carries a neurovascular bundle.
Neurovascular Bundle contains:
- Vein
- Artery
- Nerve
47
What is found in the costal groove
In the costal groove, in the intercostal space is the intercostal neurovascular bundle.
48
What is contained in the thoracic cavity?
The thoracic cavity contains the respiratory structures such as the heart and the lungs.
49
What is the pleural cavities?
The pleural cavities are the membranes that surround the lung.
50
What is pleura?
The walls of the developing lung is the pleura.
51
What are the two stages of lung development?
Embryo and Adult
52
Where does the pleural cavity exist?
The pleural cavity exists inside the chest walls.
53
How does the pleural cavity and pleura surround the developing lung?
The lung will develop by pushing into the pleura, and displace the wall around itself, so that the pleural cavity and pleura will surround the developing lung.
54
What is the parietal pleura?
Parietal pleura is the pleura that is in contact with the chest wall
55
What is the visceral pleura?
The visceral pleura is the pleura in contact with the lung.
56
What happens when the chest moves?
Anytime the chest moves, the lung will move along with it.
57
What is the most dependant part of the cavity when someone is standing up right?
The costal diaphragmatic recess is the most dependent part of the cavity when someone is standing up right (it is the most lowest.)
If there is any abnormal excess fluid, it will tend to collect in the costal diaphragmatic recess when a person is standing up.
Radiography can pick this up.
58
What are the features of the right lung?
The right lung has three lobes,
Superior, inferior and middle lobe.
The lobes are divided by fissures, the oblique fissure separates the superior lobe from the inferior lobe.
The horizontal fissure separates the superior lobe from the middle lobe.
The apex of the lung is the most superior part of the lung.
And the base which will rest down on the diaphragm.
59
What are the characteristics of the left lung?
The left lung has two lobes,
Superior lobe and inferior lobe.
The apex and the base of the lung.
There is no middle lobe, rather there is the lingula
The heart replaces the middle lobe hence why it is not present in the left lung.
60
What is the medial aspect of the lung?
The medial aspect of the lung is the hilum/root of the lung
61
What are the features of the lung hilum?
In the Lung Hilum, there are arteries and veins, and the main bronchus.
The hilum has:
- The main bronchus
- The pulmonary artery
2 pulmonary veins.
62
What are the characteristics of the hilum of the right lung?
In the middle of the lung, with the various tubings is the hilum of the right lung.
It Consists of:
The most posterior structure, which is the bronchus
The most superior structure, which is the pulmonary artery
The most anterior structure which are the pulmonary veins (2)
Pulmonary Lymph nodes which are black in anatomical specimens.
63
What are the characteristics of the left lung's surface marking and hilum?
In the hilum of the left lung, there is:
The most posterior structure, which is the bronchus/airway
The most superior structure, which is the pulmonary artery
The most inferior and anterior structures which are the pulmonary veins (2)
64
What is the primary muscle of respiration?
The diaphragm is the primary muscle of respiration.
65
How is the diaphragm supplied?
It is supplied by the phrenic nerves.
There are two phrenic nerves, a right and left phrenic nerve.
The Yellow strands in the image illustrates the phrenic nerves
The nerves descend around the heart in order to get to the diaphgram
66
What are the characteristics of the phrenic nerves?
The phrenic nerves are formed from the combined anterior rami of cervical spinal nerves C3, C4 and C5.
It is found in the neck on the anterior surface of scalenus anterior muscle.
Found in the chest (thorax) descending over the lateral aspects of the heart over the pericardium.
Supplies the diaphragm with motor and sensory fibres to the skeletal muscle of the diaphragm.
67
What does respiration mechanics involve?
It involves a complex interplay between the lungs, the chest wall, the pleura, both the visceral and the parietal pleura, and the plural cavity.
68
What are the characteristics of inspiration mechanics/how do they work?
inspiration is the process of breathing in
The process is initiated by the diaphragm contracting and descending, allowing the vertical dimensions of the chest to increase.
The intercostal muscles contracts and this pulls up the ribs
This increases the anteroposterior and transverse/lateral chest dimensions.
Because the parietal pleurae is stuck to the chest walls it creates a vacuum which pulls the visceral pleura and therefore the lungs resulting in a negative pressure gradient in the lungs, so the air flows into the lungs.
69
What is the process of expiration mechanics?
Expiration is the process of breathing out.
The diaphragm will relax and rise which decreases vertical thoracic dimensions.
The intercostal muscle relax, lowering the ribs which decreases the anteroposterior and transverse/lateral chest dimensions.
The elastic tissue of the lungs recoils causing air to flow out of the lungs.
70
What are the accessory muscles of inspiration (forced inspiration?)
Pectoralis Major and Pectoralis Minor
Sternocleidomastoid
Scalene muscles (including scalenus anterior)
71
What are the accessory Muscles of Expiration?
During forced expiration, the abdominal muscles can be used to forcefully push the diaphragm back into its resting position by forcing the abdominal contents back into the chest cavity.
72
What can Pneumothorax result in?
An injury to the chest wall results in air entering the pleural cavity via the tear in the parietal pleura, stopping the contact between the two pleuras resulting in loss of vacuum and lung collapse back to it's hilum due to elastic recoil of the lung tissues.
It can also be caused by damage to the lung tissue itself, for example by chronic cough which can result in release of air into the pleural cavity via tear in the visceral pleura and the lost of vacuum space and lung collapse.
73
What occurs if there is a foreign body within the respiratory/bronchial tree?
If there is a foreign body within the respiratory/bronchial tree,
The trachea bifurcates at the level of the sternal angle into the right and left main bronchus
The right main bronchus is wider, shorter and more vertical in comparison to the left.
A foreign body is more likely to lodge down the right main bronchus due to its larger dimensions and usually in the lower lobe of the right lung.
74
What is the mediastinum?
The Mediastinum is the area that lies in between the lungs.
It is divided into a superior and inferior mediastinum which occurs at the level of the sternal angle.
The inferior mediastinum is further divided into:
- Anterior
- Middle
- Posterior
The heart is located in the middle mediastinum.
75
What is the heart surrounded by and what is it's characteristics?
The heart is surrounded by a tough fibrous sac that is known as the pericardium.
It is made of two layers.
A fibrous thick pericardium layer, which can provide protection to the heart, such as protecting it from penetrating injuries.
However, if there is bleeding below the pericardium sac, increased pressure is built up below the fibrous pericardium which can squash the heart and prevent cardiac contraction.
The second layer is the deep layer, known as the serious pericardium.
It is membranous and glistening, and is a thin layer.
It is also known as the serous pericardium and secretes serous fluid.
76
What is the pericardial cavity and what does it contain?
the pericardial cavity contains pericardial fluid and is the enclosed sac inside the serous pericardium membrane layer.
77
Does the heart enter the pericardial cavity?
The heart pushes the pericardial layers around itself, similar to the lungs, but never enters the pericardial cavity.
78
What is the characteristics of the serous pericardium?
The Serous pericardium can be divided into two parts.
Any of the serous pericardium in contact with the fibrous pericardium is known as the parietal serous pericardium
This is the part in contact with the wall.
Any of the pink layer (the serous pericardium), in contact with a developing heart is called the visceral serous pericardium.
As the heart increases in size, the visceral serous pericardium comes into contact with the parietal serous pericardium and the parietal cavity will be very small and contain a small volume of lubricating pericardial fluid.
79
What layers of tissue does the heart contain?
The heart contains three layers of tissue:
The outermost layer is known as the epicardium, also known as the visceral serous pericardium.
The middle layer is the myocardium, which is the muscle layer.
The internal layer, at the inner wall of the myocardium, known as the endocardium which is continuous with the endothelium of the blood vessels connecting with the heart.
80
How does blood circulation occur in the heart?
The great vessels associated with the heart:
The superior vena cava
The inferior vena cava
Both enter the right atrium
Blood flows into right ventricle
Then leaves the ventricle via the pulmonary trunk, which becomes a right and left pulmonary artery that take deoxygenated blood to the lungs.
Blood is oxygenated in the lungs and return to the heart via the pulmonary veins. Oxygenated blood enters the left atrium,
blood flows into the left ventricle
Blood leaves the heart to the systems via the aorta which will arch over the top of the heart before descending posteriorly behind the heart.
81
What are the auricles of the heart?
The heart has two auricles, a left and right auricle. These are extensions of the atria and allow maximal filling of the atria.
82
What are the posterior surfaces of the heart?
The heart has the inferior surface of the heart, also known as the diaphragmatic surface of the heart. It sits on top of the diaphragm.
The heart also has the base of the heart, or the posterior surface of the heart.
The way to differentiate the base from the inferior surface is to identify the vein known as the coronary sinus. (the blue vein that sits on the edge of the base/posterior surface, next to the inferior surface.
83
What is a heart attack?
A heart attack, also known as a myocardial infarction is the irreversible death (necrosis) of part of the heart muscle (MYOCARDIUM) due to the blockage of its arterial blood supply.
The type of MI is often described clinically according to which surface of the heart has been affected, eg:
Anterior MI
Inferior MI
84
How is the myocardium supplied and what are the features of the artery that supplies it?
The myocardium is supplied with oxygenated blood via the coronary artery.
There is a right and left coronary artery.
Both arteries arise from the ascending aorta, the aorta which is the part of the aorta that ascends before it arches.
The first two branches of the aorta are the coronary arteries.
The right coronary artery has a wide distribution on the right hand side of the heart and the base of the heart.
The left coronary artery is supplying this left hand side of the heart here and again also extends posteriorly
85
How does the myocardium drain the blood?
The Myocardium also needs to have a venous drainage (deoxygnated blood needs to be taken away from the heart muscle via veins on the surface of the heart.)
The veins all drain back towards the large vein on the inferior surface of the heart known as the coronary sinus.
The coronary sinus will drain into the right atrium along with the superior and inferior vena cava.
86
How does the heart function as a pump?
The heart as a pump.
The heart is a pump that has two sides.
The right side contains venous blood, which is from the systemic circulation, heading towards pulmonary circulation
The left side is the arterial side of the heart and it contains arterial blood and it carries blood from the pulmonary circulation (from the lungs) to the systemic circulation.
The right and hand side of the heart is divided by a septum, which is a wall that divides the two structures.
The septum between the ventricles is known as the inter ventricular septum.
The septum between the atria is known as the inter atrial septum.
86
What are the cardiac valves of the heart?
Between each of the chambers and between each of the great vessels we have a cardiac valve.
Between the right atrium and right ventricle we have a tricuspid valve.
It is called a tricuspid valve due to it having three cusps associated with the valve.
Rom the right ventricle into the pulmonary trunk, we have the pulmonary valve.
It is associated with the pulmonary trunk. It is known as a semilunar valve because the cusps of the valve look like little half moons.
Blood passes through the bicuspid or mitral valve between the left atrium and left ventricle. It is called bicuspid due to it having two cusps.
Blood will enter the aorta via the aortic valve, which is between the left ventricle and the aorta, this is a semilunar valve.
86
How does deoxygenated blood circulating through the heart become oxygenated and be distributed to the systems?
Deoxygenated blood returns from the system through the superior vena cava and the inferior vena cava into the right atrium.
From the right atrium, blood will pass into the right ventricle.
From the right ventricle. Blood will then pass through the pulmonary trunk and the right and left pulmonary arteries to the lungs, where the blood will be oxygenated.
Blood will then return from the lungs via the pulmonary veins.
On both the right and the left hand side. Into the left atrium.
From the left atrium, blood will then pass into the left ventricle,
and from the left ventricle it will pass into the aorta to be distributed to the systems.
87
What does the conducting system of the heart control and what is it essential for?
The conducting system controls the spread of electrical excitation over the myocardium.
It is essential for enabling coordinated beating of chambers.
88
How does electrical activity spread?
Electrical activity will begin at the sinoatrial node.
It will then spread across the atria and will pass to the next node known as the atrioventricular node (which can take over as pacemaker).
Electrical activity will then pass down through the atrioventricular bundle of (his) into the right and left bundle branches within the interventricular septum.
Then the electrical activity will pass into the purkinje fibres which are located within the walls of the ventricle and they will bring about contraction of the ventricles.
89
How does blood pass through the cardiac valves and create the heart sounds/beat?
Deoxygnenated blood enters into the right atrium from the superior vena cava and the inferior vena cava.
At the same time, we have oxygenated blood returning to the left atrium from the pulmonary veins.
Blood will pass from the right atrium into the right ventricle via the tricuspid valve, and at the same time,
blood will pass from the left atrium into the left ventricle via the mitral or bicuspid valve.
Once the ventricles have filled, we will then get closure of the tricuspid valve and the mitral or bicuspid valve.
And it's the closure of these two valves at the same time that gives us a first heart sound.
blood will then pass from the right ventricle.
Through the pulmonary valve and the pulmonary trunk.
And at the same time, blood will pass from the left ventricle through the aortic valve into the aorta.
At the end of ventricular contraction, we will have closure of the pulmonary valve and the aortic valve again at the same time.
90
What is lymph?
When capillaries are oxygenating the tissue, a small amount of fluid will be squeezed out of the capillaries.
Most will be reabsorbed, excess fluid is called tissue fluid which is taken up by lymphatic vessels, once in lymphatic vessels, tissue fluid is called lymph.
91
What can happen if the tissue fluid is not removed?
If tissue fluid is not removed, it can build up within a tissue resulting in a condition called oedema which results in the swelling of the tissue as a result of excess tissue fluid.
92
What is the major lymphatic vessel in the body?
The major lymphatic vessel in the body is called the thoracic duct.
Drains all the grey areas in the image below.
All the grey areas will return lymph back to the thoracic duct, before the thoracic duct returns the lymph back to the veins in the left hand side of the neck at a position called the left venous angle.
The left venous angle is an angle formed between the internal jugular vein and the subclavian vein.
The pink area (the left lung) is returned to the big veins in the right hand side of the neck to the right lymphatic duct.
93
What can travel and be spread through the lymphatic system?
The pink area (the left lung) is returned to the big veins in the right hand side of the neck to the right lymphatic duct.
Cancer cells can travel and be spread through the lymphatic system.
94
What is the function of Azygous veins?
Azygous vein collects the venous blood from the intercostal spaces, drained via intercostal veins which drain back into the azygous vein which takes blood across the top of the root of the lung and into the venus cava.
95
What are the three branches/arteries coming off the arch of the aorta?
1. Brachiocephalic trunk/artery - breaks into the right common carotid artery which supplies the right hand side of the head + right subclavian artery that supplies the right arm.
2. Left common carotid artery – supplies left side of head
3. Left subclavian artery – supplies left arm
96
What are the veins within the superior mediastinum?
Internal Jugular Veins (right and left)
Subclavian Vein, (right and left)
The internal Jugular veins and subclavian veins meet to form brachiocephalic veins. (left+left = left brachiocephalic vein and mirror on right side)
The left and right brachiocephalic vein join together to form the superior vena cava.
97
What are the nerves associated with the superior mediastinum region?
Nerves associated with the region are:
Phrenic nerve, which supplies the diaphgram.
The vagus nerve
The vagus nerve also has a branch called the recurrent laryngeal nerve (has a right and left).
Yellow = nerve
Far right = phrenic nerve
Middle = vagus nerve
Left, branching up = recurrent laryngeal nerve
