RESP-anatomy Flashcards
name the 3 compartments of the pharynx in the upper respiratory tract
- nasopharynx
- laryngopharynx
- oropharynx
what are the functions of the nasal cavity?
- adjust temperature and humidity of inspired air
- trap and remove particulate matter
- drain paranasal sinuses
- olfaction
what are conchae?
aka ‘turbinates’
-shelves of bone in lateral walls of nasal cavities
what are the roles of conchae?
- > increase surface area with inspired air
- > allows rapid warming & humidification of air before it passes down into lungs
Q. Which bone are the superior & middle conchae derived from?
A-Frontal B-Nasal C-Ethmoid D-Sphenoid E-Maxillary
C
name the 4 paranasal sinuses
- frontal
- maxillary
- sphenoid
- ethmoid
(occur in pairs)
what are the functions of paranasal sinuses?
- lighten skull
- voice resonance
- shock absorption
- allows space for growth
which epithelium type lines the paranasal sinuses?
ciliated pseudostratified columnar epithelium
what does the epithelium type in the paranasal sinuses secrete?
mucus
what is the role of mucus in the paranasal sinuses?
- Mucus catches inhaled particles
- > transfers them to the nasal cavity/oropharynx for removal by coughing, swallowing or sneezing
where does the spehno-ethmoidal recess drain into (1)?
sphenoid sinus
where does the superior meatus drain into (1)?
posterior ethmoidal air cells
where does the middle meatus drain into (3)?
- anterior ethmoidal air cells
- frontal sinus
- maxillary sinus
where does the inferior meatus drain into (1)?
nasolacrimal duct (tear duct)
what is epistaxis (nose bleed) most commonly caused by?
- rupture of Kisselbach’s plexus
- due to trauma or systemic (hypertension)
what is the role of the Kisselbach’s plexus?
important site of extensive anastomosis in the anterior 1/3 of the nasal cavity
which cranial nerve is olfaction mediated by?
olfactory nerve (CN I)
where are olfactory receptors situated?
embedded within olfactory epithelium at the apex of each nasal cavity
what are olfactory receptors?
peripheral processes of bipolar sensory neurones, with cell bodies deeper in epithelium
where do olfactory receptors pass through?
-Receptors pass through perforations in the cribiform plate (part of ethmoid bone)
where do axons of the 1st order bipolar neurones pass through?
- the cribriform plate to synapse with 2nd order neurones in the olfactory bulb
- from here neurones pass posteriorly in olfactory tract-carry info about smell
what does anosmia mean?
loss/ change in sense of smell
what can permanent anosmia be caused by?
head injury, or tumours which occur in the olfactory groove (eg. meningioma)
what can temporary anosmia be caused by?
common cold, infection (eg. meningitis)
what can progressive anosmia be caused by?
neurodegenerative conditions (eg. Parkinson’s or Alzheimer’s disease)
name the 3 parts the pharynx is divided into
- oropharynx
- nasopharynx
- laryngopharynx
how is the oropharynx divided from the oral cavity?
oropharyngeal isthmus
what does the pharyngeal isthmus divide?
nasopharynx from oropharynx
what does the Eutachian tube (aka pharyngotympanic tube) connect?
nasopharynx to middle ear cavity
describe the location of the nasopharynx
- posterior to choanae
- continuous with oropharynx at pharyngeal isthmus
describe the location of the oropharynx
posterior to and divided from oral cavity by oropharyngeal isthmus
describe the location of the laryngopharynx
posterior to laryngeal inlet
what is the pharynx a common passage for?
food and air
how many pharyngeal muscles are there and what are their names?
- superior constrictor
- middle constrictor
- inferior constrictor
what is the shape of the pharyngeal muscles?
circular
what is the role of the pharyngeal muscles?
contract to push food bolus down oesophagus
what type of muscles are the pharyngeal muscles?
skeletal muscles
rest of GI musculature is smooth
where in the pharynx are the longitudinal muscles located?
deep to circular muscles
name the 3 longitudinal muscles of the pharynx
- salpinopharyngeus
- palatopharyngeus
- stylopharyngeus
what is the role of the longitudinal pharyngeal muscles?
-> elevate & shorten pharynx, so food bolus can be pushed down into the oesophagus
what is the additional role of the salpinopharyngeus?
-> salpingopharyngeus also opens the pharyngeal orifice of the Eustachian tube during swallowing- allowing for the equalization of pressure between it and the pharynx
what are tonsils?
collection of lymphoid tissue in pharyngeal mucosa
where are tonsils in the upper respiratory tract?
surrounding openings of oral and nasal cavities
what is the role of tonsils in the upper pharyngeal tract?
Form a defence system present in upper respiratory tract
what is Waldeyer’s ring?
ring of lymphoid tissue
name the 3 tonsils in the upper respiratory tract
- pharyngeal (Adenoids)
- palatine
- lingual
what are the functions of the larynx?
- functions as a valve to close lower respiratory tract
- instrument to produce sound (voicebox)
what is the larynx composed of?
- 3 paired cartilages
- 3 unpaired cartilages
name the 3 unpaired cartilages
- epiglottis
- thyroid
- cricoid
name the 3 paired cartilages
- arytenoid
- corniculate
- cuneiform
at which level does the trachea begin?
C6
-level of cricoid cartilage
what is the vocal ligament formed by?
- upper free margin of cricothyroid ligament
- extending between thyrpid cartilage and arytenoid cartilage
- underlines the true vocal fold
what does the cricothyroid ligament form?
thickens in the midline to form median cricothyroid ligament
name the internal ligament of the larynx
cricothyroid ligament
name the internal ligament of the larynx
quadrangular membrane
what is the role of the quadrangular membrane?
role in protecting the entrance to the trachea
where doe the quadrangular membrane extend between?
- lateral margin of epiglottis to arytenoid cartilage on either side
- has free upper and lower margin
- vestibular fold overlies vestibular ligament
is the quadrangular membrane a true or false vocal cord?
false
which cranial nerve innervates the larynx?
vagus nerve (CN X)
which muscles does the recurrent laryngeal muscle innervate?
all muscles of the larynx except cricothyroid
where does the right recurrent laryngeal nerve hook underneath?
underneath right subclavian artery
where does the left recurrent laryngeal nerve hook underneath?
arch of aorta
what innervates the cricothyroid muscle?
external branch of superior laryngeal nerve
what is the function of the criocothyroid muscle?
elongates vocal fold, so allows for higher pitch voice
where does the right recurrent laryngeal originate?
in the root of the neck
what is the role of the recurrent laryngeal?
sensory below vocal cords and motor to all except cricothyroid muscle
what is the role of the superior laryngeal?
gives off external and internal laryngeal
what is the role of the internal laryngeal?
sensory above vocal cords
where does the superior thyroid artery branch off?
external carotid artery
which artery does the superior thyroid give off?
superior laryngeal artery
where does the inferior thyroid artery branch off?
thyrocervical trunk
which artery dies the inferior thyroid artery give off?
inferior laryngeal artery
what is the trachea?
airway between larynx and primary bronchi
at which level does the trachea begin?
C6
at which level does the trachea bifurcate?
at level of carina/ sternal angle (of Louis)
–>T4
how is the patency (openness) of the trachea maintained?
maintained by cartilage
what is the shape of cartilage in the trachea and why?
C-shaped rings
->posterior border is soft to allow for expansion of the oesophagus for swallowing
which muscle makes up the posterior border of the the trachea?
trachealis muscle
what divides the lungs into lobes?
fissures
how many lobes does the left lung have?
2 lobes
-superior and inferior
what divides the lobes of the left lung?
oblique fissure
how many lobes does the right lung have?
3 lobes
-superior, middle and inferior
what divides the lobes of the right lung?
horizontal and oblique fissures
how many bronchopulmonary segments does the right lung have?
10 BP segments
how many bronchopulmonary segments does the left lung have?
8-10 BP segments
what are BP segments?
the tissue served by a single tertiary bronchus
what separates BP segments?
connective tissue
how are BP segments functionally independent?
- own vasculature/ lymph etc.
- surgically resectable
what are the differences between the right and left primary bronchus?
right
- wider
- shorter
- more vertical
left
- narrower
- longer
- more horizontal
which primary bronchus is more vertical?
right
which lung is an aspired foreign body more likely to enter?
right as primary bronchi is wider and more vertical
outline the order for the passage of air
trachea->primary bronchi (R/L) ->secondary bronchi (R/L)->terminal/ tertiary bronchi->bronchioles->alveoli
what is another name for tertiary/ terminal bronchi?
segmental bronchi
which part of the airways is the last with cartilage?
terminal bronchi
what are the 3 types of bronchioles?
- conducting
- terminal
- respiratory (because of alveoli)
what is the lung root?
collection of structures entering and exiting the lung at its hilum
what is the name of the point of entry for the bronchus, blood vessels and nerves?
hilum
which structures cause an impression on the right lung?
SVC, azygos vein & oesophagus
which structures cause an impression on the left lung?
aorta, aortic arch and descending aorta
what are the functions of the chest wall?
- protect viscera
- facilitate breathing
what causes the ribs to move?
contraction of intercostal muscles
which ribs make up the pump handle?
ribs 2-6
what is the function of the pump handle?
increases anterior-posterior dimension during inspiration
which ribs make up the bucket handle?
ribs 7-10
what is the function of the bucket handle?
increases lateral dimension during inspiration
what happens to the diaphragm during inspiration?
- diaphragm flattens downwards (increases superior-inferior dimension)
- increases overall thoracic volume
where is the intercostal neurovascular bundle found between?
between internal intercostal muscle and innermost intercostal muscle
what is the effect of the external IC muscles on ribs?
elevate ribs
when do external IC muscles work?
quiet and forced inspiration
what is the effect of the internal IC muscles on ribs?
depress ribs
when do internal IC muscles work?
forced expiration (quiet expiration is passive)
what is the role of innermost intercostals?
- insignificant
- thought to act with internals
what is the role of the diaphragm?
principle muscle of respiration
what innervates the diaphragm?
phrenic nerve
C3-5
at which level does the IVC pass through the diaphragm?
T8
at which level does the oesophagus and vagus nerve pass through the diaphragm?
T10
at which level does the aorta and cisterna chyli pass through the diaphragm?
T12
what does the parietal pleura line?
the wall of thoracic cavity
what does the visceral pleura line?
the surface of lungs
where do the 2 types of respiratory pleura connect?
at the lung root
what is the pleural cavity?
potential’ space between parietal and visceral pleura- small in an inflated lung & large in a collapsed lung
what does the pleural cavity contain?
serous fluid secreted by pleura
what is the role of serous fluid in the pleural cavity?
increases in volume when diaphragm contracts
what is negative pleural pressure?
pressure in pleural cavity is less than (‘negative’) atmospheric pressure
what does negative pleural pressure cause?
forces lung expansion and drives ventilation; if greater than atmospheric pressure, can cause lung collapse
what is it called when there is air inside the pleural cavity?
pneumothorax
how is fluid drained from the lungs?
thoracocentesis
what is pleural effusion?
when fluid (even gas) collects in pleural cavity recesses in excess
what are the names of the 2 pleural cavity recesses (where the lung doesn’t fill the entire thoracic space)?
- costodiaphragmatic recess (CDR)
- costomediastinal recess (CMR)
