lungs and respiratory tract Flashcards
name 3 functions of the upper respiratory tract
- warms, humidifies and filters the air
- olfaction (smell)
- production and resonation of sound
name the 4 components of the upper respiratory tract
- nose
- paranasal sinuses
- pharynx
- larynx
what are vibrissae and what are their function?
short thick hairs at the entrance of the nose — filter particles
what are conchae and what are their functions?
bones in the nose — produce turbulent flow, increase time for warming and filtering the air
what is the epithelium of the upper respiratory tract? function?
pseudostratified ciliated columnar epithelium — mucocilary escalator
what is the purpose of a rich capillary network in the upper respiratory tract?
warms air
what is the function of serous glands in the upper respiratory tract?
humidifies air
what does the olfactory mucosa contain?
receptors for smell
what concha are there?
3 — superior, middle and inferior nasal concha
what is the name of the recess above the superior nasal concha?
the sphenoethmoidal recess
what is the name of the recess below the superior nasal concha?
superior meatus
what is the name of the recess below the middle nasal concha?
middle meatus
what is the name of the recess below the inferior nasal concha?
inferior meatus
what are the paranasal sinuses?
air filled spaces that communicate with the nose
what are the 4 paranasal sinuses?
sphenoid, frontal, ethmoid, maxillary
what are the functions of the paranasal sinuses?
lighten the weight of the skull, resonance of sound
what are the paranasal sinuses lined by?
pseudostratified ciliated columnar epithelium with goblet cells
which sinus provides surgical access to the pituitary gland?
sphenoid
which sinus is most likely to get blocked?
maxillary
describe the frontal paranasal sinus
- there are 2
- most superior of the sinuses
- triangular shape
- located within the frontal bone of the skull
- opens into hiatus semilunaris, within the middle meatus
describe the sphenoid sinus
- in the body of the sphenoid bone
- open into sphenoethmoidal recess
- gives access to pituitary gland
describe the ethmoidal sinus
- 3
- located in ethmoid bone
- 1 = anterior — opens onto the hiatus semilunaris - middle meatus
- 2 = middle — opens onto the lateral wall of the middle meatus
- 3 = posterior — opens onto the lateral wall of the superior meatus
describe the maxillary sinus
- largest sinus
- they are located laterally and slightly inferiorly to the nasa; cavities
- drain into the nasal cavity at the hiatus semilunaris, under the frontal sinus opening — potential pathway for spread of infection
- fluid from the frontal sinus can enter the maxillary sinus
what does the epiglottis ensure?
that food doesn’t pass into the airways when swallowing
how does the epiglottis work?
it is pushed back by food and the pharynx and larynx are elevated so that the epiglottis covers the laryngeal inlet. the vocal cords are abducted to close the glottis
what are the 3 surfaces of the lungs?
diaphragmatic, costal, mediastinal
where does the trachea bifurcate?
at the carina
what spinal level does the trachea begin at?
C6
where does the trachea bifurcate (surface anatomy)?
at sternal angle (lower border of T4, rib 2)
what does the trachea contain to ensure it stays open at all times?
horseshoe shaped rings of cartilage
what is the trachealis muscle? function?
a thick band of smooth muscle that bridges the ends of the cartilage — stabilises the entire length of the trachea
how many lobes does the right lung have and what are they?
3 — superior, middle, inferior
how many lobes does the left lung have and what are they?
2 — superior and inferior
what fissures are present in each lung?
right — horizontal and oblique
left — oblique
where are the apices of the lungs?
above the clavicles
where can the middle lobe be auscultated anteriorly?
between the 4th-6th ribs
name main parts of the larynx (ascending to descending)
- epiglottis
- hyoid bone
- thyroid cartilage
- arytenoid cartilages
- cricoid cartilage
- corniculate cartilages
what is present at the hilum on the mediastinal surface of the right lung?
- right primary bronchus
- pulmonary veins
- pulmonary arteries
- bronchial vessels, lymphatics, autonomic nerves
what 2 impressions are present on the mediastinal surface of the right lung?
- impression formed by the SVC
- impression formed by the azygos vein
what is present at the hilum on the mediastinal surface of the left lung?
- left primary bronchus
- pulmonary veins
- pulmonary arteries
what impressions are there on the mediastinal surface of the left lung?
- impression formed by the aortic arch
- impression formed by the thoracic aorta
- impression formed by the heart
what innervation does the parietal pleural receive?
somatic sensory
where does the internal thoracic artery arise from?
subclavian artery
what are the 2 terminating branches of the internal thoracic artery?
musculophrenic and superior epigastric arteries
what is the arterial blood supply of the lungs?
comes from the right and left pulmonary arteries (originate from the pulmonary trunk)
what is the venous drainage of the lungs?
- pulmonary veins (2 for each lung)
- in both lungs, the superior and inferior pulmonary veins receive blood from the superior and middle lobes (except the left, where blood is from the lingula instead of the middle lobe), and the lower lobe respectively and drain into the left atrium of the heart
right superior vein — superior and middle lobe
right inferior vein — inferior lobe
left superior vein — superior lobe
left inferior vein — inferior lobe
the bronchi, lung roots, visceral pleura and supporting lung tissues require an extra nutritive blood supply. what are they delivered by and where do they arise?
bronchial arteries, which arise from the descending aorta
what supply venous drainage to these?
bronchial veins
where do the right and left bronchial veins drain into?
right — azygos vein
left — accessory hemiazygos vein
what drains the lymph from the lung parenchyma?
superficial (subpleural) lymphatic plexus
what drains lymph from the structures of the lung root?
deep lymphatic plexus
what do the superficial and deep lymphatic plexuses drain into? where does lymph pass into from here?
- the trachebronchial nodes — located around the bifurcation of the trachea and main bronchi
- then into the right and left bronchomediastinal trunks
what is the nerve supply of the lungs derived from?
pulmonary plexuses
what is the parasympathetic innervation of the lungs? effect?
derived from vagus nerve — stimulate secretion from the bronchial glands, contraction of the bronchial smooth muscle, and vasodilation of the pulmonary vessels
what is the sympathetic supply of the lungs? effect?
derived from the sympathetic trunks — stimulate relaxation of the bronchial smooth muscle, and vasoconstriction of the pulmonary vessels
what is the visceral afferent innervation of the lungs?
conducts pain impulses to the sensory ganglion of the vagus nerve
what are the parietal and visceral pleura sensitive to?
parietal — pressure, pain, and temperature
visceral — not sensitive to these
what is the parietal pleura innervated by?
phrenic and intercostal nerves
what is the blood supply of the parietal pleura?
intercostal arteries
what do the sensory fibres of the visceral pleura detect>?
stretch
what is the autonomic innervation of the visceral pleura?
pulmonary plexus (a network of nerves derived from the sympathetic trunk and vagus nerve)
what is the arterial supply of the lungs and what are they branches of?
bronchial arteries — branches of the descending aorta, which also supply the parenchyma of the lungs
