Anatomy Flashcards
What makes up the upper respiratory tract?
Right & left nasal cavities
Oral cavity
Naso-/Oro-/Laryngo- pharynx
Larynx
What makes up the lower respiratory tract?
Trachea Right & left main bronchi Lobar bronchi Segmental bronchi Bronchioles Alveoli
What is the division between the URT and LRT?
The trachea
At which level does the larynx (URT) become the trachea (LRT)?
C6 vertebrae
The trachea can be palpated at the ________
Jugular notch of the manubrium
The isthmus of the thyroid gland is anterior to the tracheal cartilages ___
2-4
What connects the right and left side of the thyroid gland (forms an H shape)
Isthmus
Where is the thorax?
Between the neck and the abdomen
What are the components of the thorax?
Chest walls
Chest cavity
What is the function of the chest wall?
Protection of the heart and lungs
Making the movements of tissue
Breast tissue –> lactation
Where is the chest cavity located?
Within the chest walls
What does the chest cavity contain?
Vital organs (Viscera) + major vessels and nerves
What does the chest cavity consist of?
Mediastinum & right and left plural cavities
What are the layers of the chest wall (superficial to deep)?
Skin
Fascia (Superficial then deep)
Bone / Joints
Parietal pleura
The chest cavity is divided into which 3 areas?
Left pleural cavityRight pleural cavityMediastinum (in between)
The pleura in contact with the chest wall is called ____ pleura
Parietal
The pleura in contact with the lungs is called ___ pleura
Visceral
What does the pleural cavity contain?
Pleural fluid
What is the function of pleural fluid?
Cause surface tension between parietal and visceral pleura
Acts as a lubricant
Each lung has __ Brunchopulmonary segments
10
How many lobes does the right lung contain?
3
Which lung contains 2 lobes?
Left lung
Does each bronchopulmonary segment have its own blood supply?
Yes
What defines a true rib?
Attach via their costal cartilage to the sternum via a single bar or cartilage
What defines a false rib?
Attach via costal cartilage above to the sternum (via common costal cartilage = costal margin)
What defines floating ribs?
No attachment to the sternum
Which are the true ribs?
1-7
Which are the false ribs?
8-10
Which are the floating ribs?
11-12
How many intercostal spaces are there?
11
What makes up the sternum?
Manubrium
Body
Xiphoid
Sternal angle
What are the joints of breathing and where are they found?
COSTOVERTEBRAL: Between ribs and vertebrae
COSTOCHONDRAL: Between ribs and costal cartilage
STERNOCOSTAL: Between the sternum and the costal cartilage
Which layers of skeletal muscle are located between the ribs & within the intercostal spaces (superficial to deep)?
External intercostal muscles
Internal intercostal muscles
Innermost intercostal muscles
Where do the layers of intercostal muscles attach?
Between adjacent ribs
How do the intercostal muscles make the chest wall expand during breathing?
By pulling adjacent ribs upwards and outwards
What is the main skeletal muscle of breathing?
The diaphragm
What does each intercostal space carry? Where is this located?
A neuro-vascular bundle between internal and innermost intercostal muscle layers
What constitutes a neuro-vascular bundle?
Nerve, Artery &Vein
What is the nerve supply to the intercostal spaces?
Anterior rams of spinal nerve (aka intercostal nerve)
What is the posterior arterial supply to the intercostal spaces?
Thoracic aorta
What is the anterior arterial supply to the intercostal spaces?
Internal thoracic artery
What is the posterior venous drainage of the intercostal spaces?
Azygous vein
What is the anterior venous drainage of the intercostal spaces
Internal thoracic vein
The intercostal spaces have ___ arterial and venous supply
Dual
Which arteries supply the chest wall?
Bilateral posterior intercostal arteries
The bronchial arteries are branches from the anterior surface of the ______
Thoracic aorta
The thoracic duct accompanies the ____ through the diaphragm
Aorta
What forms the floor of the chest cavity?
Diaphragm
What forms the roof of the abdominal cavity?
Diaphragm
The diaphragm has _____ to allow structures to pass
opening
What type of muscle is the diaphragm?
Skeletal muscle with central tendon
Why is the right dome of the diaphragm normally more superior than the left?
Because of the presence of the liver inferiorly
The muscular part of the diaphragm attaches peripherally to (anterior to posterior)?
- Sternum
- Lower 6 ribs & costal cartilage
- L1-L3 vertebral bodies
What is the nerve supply of the diaphragm?
Phrenic nerve
Where does the phrenic nerve originate from?
C3,4 & 5 anterior rami
keep the diaphragm alive
The phrenic nerve is found on the anterior aspect of the ______ muscle and descends over the _____ aspects of the heart
Scalenus anterior
Lateral
The phrenic nerves supply the _____ and ______ axons to the diaphragm & ______
Somatic sensory
Sympathetic
Fibrous pericardium
The phrenic nerve supplies somatic _____ axons to the diaphragm
Motor
What are the 3 steps of inspiration mechanics?
Diaphragm contracts and descends
Intercostal muscles contract and elevate ribs
Chest walls pull the lungs outwards with them (parietal pleura)
What does the diaphragm contracting do to the vertical chest dimension?
Increases it
Which chest dimensions are increased by the intercostal muscles contracting?
A-P and lateral
What effect does the chest wall pulling the lungs outwards have?
CREATES NEGATIVE PRESSURE
Air flows into the lungs
What are the 3 steps of expiration mechanics?
Diaphragm relaxes and rises
Intercostal muscles relax lowering ribs
Elastic tissue of lungs recoils
The lateral quadrants to axillary nodes in the breast show _____ drainage
Unilateral
The medial quadrants to parasternal nodes show _____ drainage
Bilateral
Where does blood supply to the breast come from?
Internal thoracic artery which comes from the subclavian vein
What is the groove in between the pectorals major and deltoid called?
Deltopectoral groove
Which vein drains the upper limb and drains into deeper veins in the neck?
Cephalic vein
Where is the costodiaphragmatic recess located?
Between the diaphragmatic parietal pleura and the costal parietal pleura
What is the most inferior region of the costodiaphragmatic recess, laterally?
The costophrenic angle
Abnormal fluid in the pleural cavity drains into the _______
Costodiaphragmatic recess
What is auscultation
Listening to the sound of air moving through the larynx
Which parts of the lung need to be auscultated during an exam?
All 5 lung lobes
Apices
Bases
Describe the dual blood supply to the lungs
OXYGENATED BLOOD
Pulmonary veins x 4
Bronchial arteries
DEOXYGENATED BLOOD
Pulmonary arteries x 2
Bronchial veins
What are the two types of bronchi?
LOBAR - provide lung lobes with air
SEGMENTAL - provide bronchopulmonary segments with air
The sternal angle is at what rib level?
Level of rib 2
Which area on the ribs carriers the intercostal NVB?
Costal groove
Which nerve innervates serratus anterior? Injury to this nerve causes what?
Long thoracic nerve
Winged scapula
What are the structures of the lung root?
Main bronchus Pulmonary veins x 2 Pulmonary artery Lymphatics Sensory visceral afferents Sympathetic and parasympathetic nerves
Coughing occurs in response to the stimulation of receptors in _______ (3)
Oropharyngeal mucosa
Laryngopharyngeal mucosa
Laryngeal mucosa
From which cranial nerve will the nasopharynx and oropharynx relay action potentials from?
CN IX (Glossopharyngeal nerve)
From which cranial nerve does the laryngopharynx relay action potentials from?
CN X (Vagus nerve)
What are carotid sheaths?
Protective “tubes” of cervical deep fascia
Where do the carotid sheets attach?
Superiorly to the bones of the base of the skull
Blend inferiorly with the fascia of the mediastinum
What do the carotid sheaths (right/left) contain? (4)
Vagus nerve
Internal carotid artery
Common carotid artery
Internal jugular vein
How do visceral pleura and respiratory tree visceral afferents connect with the CNS? (3)
Sympathetic trunk
Pulmonary plexus
Vagus nerve (in the carotid sheath)
What is meant by “visceral afferent”?
Sensory nerve (that arrives) from an organ
What does the pulmonary plexus contain? (3)
Sympathetic axons
Parasympathetic axons
Visceral afferents
What is a plexus?
An intertwining of nerves
The sympathetic and parasympathetic axons in the pulmonary plexus are _____ nerves that supply the _____
Motor
Heart
The motor axons travel from the tracheal _____ along the branches of the _________ to supply all ____ and ______
Bifurcation
Respiratory tree
Mucous glands
Bronchiolar smooth muscles
Describe the route of the pulmonary visceral afferents from the visceral pleura to the medulla
From visceral pleura
Respiratory tree to the plexus then follow the vagus nerve to the medulla to the brain
Once the sensory receptors have been stimulated the CNS responds by rapidly coordinating _____
Deep inspiration
Deep inspiration requires use of ___(4)
Diaphragm
Intercostal muscles
Accessory muscles of inspiration
Which nerves innervate the diaphragm?
Phrenic nerves
Which nerves innervate the intercostal muscles?
Intercostal nerves
What is the difference between quiet and forced inspiration in terms of action potentials via the phrenic nerves?
In deep/forced inspiration a greater outflow of action potentials with a longer duration cause the diaphragm to flatten and descend maximally
The intercostal nerves are the anterior rami of which spinal nerves?
T1-T11
What are the accessory muscles of forced / deep inspiration?
Pectoralis Major
Pectoralis minor
Sternocleidomastoid
Scalenus anterior, posterior
Where does the pectoralis major attach?
Between the sternum/ribs and humerus
What is the function of the pectoralis major?
Adduction and medial rotation of the humerus
What position must the upper limb be in so the pectoralis major can pull the ribcage upwards/outwards?
Upper limb position is “fixed” E.g. by holing on to the air of the chair or the thigh
What is the recruitment of accessory muscles a clinical sign of
Dyspnoea?
What is the function of the pectoralis minor in terms of deep inspiration?
Puling ribs 3-5 superiorly towards the coracoid process of the scapula
Where does the sternocleidomastoid attach?
Between the sternum/clavicle and mastoid process of the temporal bone
Where do the scalenus anterior, medius & posterior attach?
Between cervical vertebrae; ribs 1 and 2
Which nerve stimulates the adduction of the vocal cords to close the rims glottidis during the coughing reflex?
CN X - Vagus nerve
Where do the intrinsic muscles of the larynx attach?
Between the cartilages
What do the intrinsic muscles of the larynx move? What does this result?
The cartilages - movement of the vocal cords
What type of muscle are the intrinsic muscles of the larynx?
Skeletal (voluntary) muscle
What type of nerve is CN X?
Mixed (sensory and motor)
Where does the cranial nerve connect with the CNS?
At the medulla oblongata of the brainstem
Through which structure do the vagus nerves (left&right) pass through the neck?
Within the carotid sheath
What is the important function of CN X to coughing?
Supply somatic sensory and somatic motor axons to the larynx
To which part of the larynx do the sensory parts of CNX go?
Mucosa lining of the larynx
To which part of the larynx do the motor parts of CNX go?
Intrinsic muscles of the larynx
In the chest, the vagus nerves descend ______ to the chest organs (including the lungs via the pulmonary plexus
Posterior
The vagus nerves pass through the diaphragm on the _______
Oesophagus
Where do the vagus nerves divide into many parasympathetic braches?
On the surface of the stomach
Which structures do the parasympathetic branches of the vagus nerve supply? (2)
Foregut and Midgut organs
Does the vagus or the phrenic nerve pass anterior to the root of the lung?
The phrenic nerve
What is the purpose of anterolateral abdominal wall muscle contraction in terms of the cough reflex?
Raise intra-abdominal pressure
Which muscles forcefully increase the the intra-abdominal pressure during deep expiration?
Right left anterolateral abdominal wall and the diaphragm
Which muscles are involved in deep expiration? (4 - right and left of each)
Rectus abdominis
External oblique
Internal oblique
Transverses abdominus
What is an aponeurosis?
Flattened tendon
The aponeurosis of the right external oblique blends with the aponeurosis of the left external oblique the the midline ________
Linea alba
Where does the external oblique attach superiorly?
Superficial aspects of the lower ribs
Where does the eternal oblique attach inferiorly?
Anterior part of the iliac crest and the pubic tubercle
The fibre direction of the external oblique is the _____ as the external intercostal muscle
Same
Where is the lines semilunaris?
Where the muscle fibres end and the aponeurosis begins
_____ of the right internal oblique bless with the aponeurosis of the _______ at the midline linea alba
Aponeurosis
Left internal oblique
Where does the right internal oblique attach superiorly?
The inferior border of the lower ribs
Where does the internal oblique attach inferiorly?
Iliac crest and thoracolumbar fascia of the lower back
Does the internal oblique have the same/opposite fibre direction as the internal intercostal muscles?
Same
Where does aponeurosis of the right transverses abdomens blend with the aponeurosis of the left transversus abdomens?
Linea alba
Where does the transversus abdominus attach superiorly?
Deep aspects of the lower ribs
Where does the transversus abdominus attach inferiorly?
Iliac crest and thoracolumbar fascia of the lower back
What encapsulates the rectus abdominus?
Internal oblique
External oblique
Skin
Transversus abdominis
Where does the the rectus abdominis attach superiorly?
Xiphoid process
Costal margin
Where does the rectus abdominis attach inferiorly?
Pubis bone
Pubic symphysis
The somatic motor, somatic sensory and sympathetic nerve fibres supplying the structures of the abdominal part of the body wall (soma) are convey within the _____
Thoracoabdominal nerves
The 7th-11th intercostal nerves travel ______ then their terminal branches leave the _________ in which plane?
Anteriorly
Intercostal spaces
In the plane between the internal oblique and transversus abdominus
What is the name of the nerves in the plane between the internal oblique and transversus abdominus?
Thoracoabdominal nerves
What innervates the upper part of the abdominal wall?
Thoracoabdominal nerves
What innervates the area below T12?
Subcostal nerve
What does the iliohypogastric nerve innervate?
Half of L1 anterior ramus
What does the ilioinguinal nerve innervate?
Half of L1 anterior ramus
What are the functions of tonic (continuous low level) contractions of anterolateral abdominal muscles?
Maintain posture
Support the vertebral column
What are the function of contractions of the anterolateral abdominal muscles?
Movements of the vertebral column (flexion; lateral flexion; rotations)
Guarding - protect the abdominal viscera
Increase intra-abdominal pressure (to assist defecation; micturition; labour)
Aid forced expiration
What is a pneumothorax?
Alveolar air in the pleural cavity
How can dynamic airway compression in asthma lead to a pneumothorax?
Expiration is difficult and the build-up of air trapped in alveoli can lead to rupture of lung and visceral pleura
By which mechanism is a pneumothorax developed?
Penetrating injury to parietal pleura or rupture of visceral pleura; loss of vacuum; elastic recoil of lungs towards lung root
What classifies a small pneumothorax?
2 cm between lungs and parietal pleura
What classifies a large pneumothorax?
> 2 cm between lungs and parietal pleura
How is a pneumothorax diagnosed by examination?
Reduced ipsilateral chest expansion
Reduced ipsilateral breath sounds
Hyper-resonance on percussion
How can a pneumothorax be diagnosed by investigation via a CXR?
Absent lung markings peripherally
Visible lung edge
How does a tension pneumothorax develop?
Torn pleura creating a one-way valve allowing air to enter pleural cavity on inspiration but not expiration
What consequence can follow a tension pneumothorax?
Mediastinal shift
How can mediastinal shift, and therefore a tension pneumothorax, be diagnosed?
Deviation of the trachea - palpable on jugular notch
What is the consequence of mediastinal shift?
SVC compression reduces venous return to the heart causing hypotension
How is a large pneumothorax managed (2)?
Needle aspiration (thoracentesis) Sitting of chest drain
Where should the needle enter to relieve a large pneumothorax?
4th or 5th intercostal space in the mid-axilliary line
How would you emergency manage a tension pneumothorax?
Insert large gauge cannula into pleural cavity via 2nd or 3rd intercostal space in the mid-clavicular line on the side of the tension pneumothorax
What is a hernia?
Any structure passing through another (i.e. ending up in the wrong place)
What is required for a hernia to develop?
Weakness of one structure (normal/congenital/surgical scar) + increased pressure on one side of that part of the wall
Why can a chronic cough cause a hernia?
Regular increase in intra-abdominal pressure on diaphragm, anterolateral abdominal walls (including inguinal region + femoral triangle)
Where do diaphragmatic hernia tend to develop?
Xiphoid attachment
Posterior attachments
Oesophageal hiatus
What distinguishes a paraoesophagheal hiatus hernia?
Herniated pert of stomach passes through oesophageal hiatus to become parallel to the oesophagus in the chest - Gastro-oesophageal junction doesn’t move
What distinguishes a sliding hiatus hernia?
Herniated part of the stomach slides through oesophageal hiatus into the chest with the gastro-oesophageal junction
Where do inguinal hernias occur?
Uni-/bilateral
Medial halves of inguinal region
What weakness and which pressure cause inguinal hernias?
Weakness = presence of inguinal canal Pressure = intra-abdominal
What can cause an inguinal hernia?
Chronic cough or constipation
Occupational heavy lifting
Athletic effort
Where is the inguinal canal?
Between deep ring and superficial ring
Where is the inguinal region?
Between anterior superior iliac spine and pubic tubercle
What guides the testicle from its origin point in the abdomen down through the abdominal wall into the scrotum?
The gubernaculum
How does the testicle descend from the abdomen to the scrotum?
Testicle starts to push into transversalis fascia (drags some with its)
Bypasses transverse abdominus
Crosses internal oblique (drags some with)
Passes through superficial ring of pubic tubercle
Passes through superficial fascia (drags some with)
What does the layer of transversals fascia become known as when covering the testis?
Internal spermatic fascia
What does superficial fascia become known as later on when it covers the testis?
External spermatic fascia (covering of external oblique aponeurosis)
What does the internal oblique become known as later on when it covers the testis?
Cremasteric fascia
The structures that the testes dragged with it become known as the ____
Spermatic cord
Small part of peritoneum remained in scrotum after descending of testis becomes known as the ______
Tunica vaginalis
The point between the deep and superficial ring is the _____
Inguinal canal
The deep ring is where the the testes pushed into the ________
Transversals fascia
The superficial rings is where the testes pushed into the _______ of the scrotum
Superficial fascia
What does the spermatic cord contain?
Vas deferens
Testicular artery
Pampiniform plexus of veins
What is the function of the vas deferens?
Transports sperm
What are the boundaries of the femoral canal?
Anterior = inguinal ligament Medial = lacunar ligament Lateral = femoral vein Posterior = pectinate ligament
What is a direct inguinal hernia?
Finger of peritoneum is forced through posterior wall of inguinal canal and directly out of superficial ring into the scrotum
What is an indirect inguinal hernia?
Finger of peritoneum is forced through the deep ring into the inguinal canal, then out of the superficial ring into the scrotum
How do you clinically differentiate between direct and indirect inguinal hernias?
- Reduce hernia
- Occlude deep ring with fingertip pressure
- Ask patient to cough
If direct, lump will reappear
If indirect, lump will not reappear
