respiratory anatomy Flashcards
superior thoracic aperture
the opening at the top of the thoracic cavity
anatomically - thoracic inlet
clinically - thoracic outlet
what is the superior thoracic aperture bounded by
- T1 posteriorly
- 1st pair of ribs laterally
- costal cartilage of the 1st rib and the superior border of the manubrium anteriorly
what is the inferior thoracic aperture bounded by
- T12 posteriorly
- 11th and 12th pair of ribs laterally
- costal cartilage of ribs 7-10 and the xiphisternal joint anteriorly
how it the rib cage separated from the peritoneal cavity
the thoraco-abdominal cavity
define diaphragm
fibromuscular membrane stretched across the midline of the body
the head of the rib articulates with …
the body of the thoracic vertebra of the same number AND the body of the vertebra above at the costovertebral joints (synovial plane)
the tubercle of the rib articulates with …
the transverse process of the thoracic vertebra of the same number at the costotransverse joint (synovial plane)
describe the shape of the 1st rib
broad and flat
surfaces look up and downward
describe the head of the 1st rib
possesses only a single articular facet (most have 2) for articulation with the body of T1
describe the upper surface of the body of the 1st rib
marked by 2 shallow grooves
separated by the scalene tubercle (attachment of the anterior scalene muscle)
anterior groove lodges the subclavian vein and the posterior groove for the subclavian artery and the lowest trunk of the brachial plexus
what are the 3 peripheral attachments of the diaphragm
- lumbar vertebrae and arcuate ligaments
- costal cartilages of ribs 7-12
- xiphoid process of the sternum
what is the central attachment of the diaphragm
central tendon
describe the parts of the diaphragm that arise from the vertebrae
they are tendinous in structure and are known as the R and L crura
right crus
arises from L1-L3
some fibres of the right crus surround the oesophageal opening and help prevent reflux of gastric contents back into the oesophagus
left crus
arises from L1-L2 and their intervertebral discs
what happens during inspiration to the diaphragm
insp: contracts and descends, domes flatten, increases the vertical diameter of the thoracic cavity
how many openings are there in the diaphragm and what are these known as
3 hiatuses
where are the diaphragm hiatuses located
T8, T10, T12
T8 diaphragm hiatus
caval opening passes through the central tendon of the diaphragm
transmits the IVC and the R phrenic nerve from the abdomen into the thorax (tendon can’t contract and impede blood flow)
T10 diaphragm hiatus
oesophageal hiatus
located through the muscular sling of the R crus
transmits the oesophagus and both vagus nerves
T12 diaphragm hiatus
aortic hiatus
between the R and L crus
transmits the aorta, azygos veins, hemiazygos vein and thoracic duct
phrenic nerve roots
anterior rami of C3,4 (mainly) and C5
it is both motor and sensory
what are the motor functions of the phrenic nerve
pierces and innervates the diaphragm from its anterior surface
what are the sensory functions of the phrenic nerve
supplies the central part of the diaphragm
peripheral portions are also innervated by sensory fibres of the intercostal nerves T7-12
lymphatic drainage of the chest wall
L side drains to thoracic duct (–> L brachiocephalic vein)
R side drains to R lymphatic duct (–> R brachiocephalic vein)
upper respiratory tract
part of the respiratory system lying above the sternal angle or above the cricoid cartilage
the larynx is sometimes included in the upper and lower airway
lower respiratory tract
trachea, bronchi, bronchioles, lungs (including alveoli)
also sometimes includes the larynx
what is the respiratory/tracheobronchial tree refering to
the branching structure of airways supplying air to the lungs
includes the trachea, bronchi and bronchioles
what is included in the conducting portion
no gas exchange
- trachea
- main bronchus
- lobar bronchus
- segmental bronchus
- conducting bronchiole
- terminal bronchiole
what is included in the respiratory portion
gas exchange occurs
- respiratory bronchiole
- alveolar duct
- alveolar sac
- alveolus
where is the larynx found
in the anterior neck between C3-6
extends from the tip of the epiglottis to the inferior border of the cricoid cartilage
what innervates the larynx
branches of the vagus nerve
what are the 3 borders of the lungs
anterior, posterior, inferior
what are the 4 lobes of the lungs
superior
inferior
middle (R only)
lingula (L only)
what are the 3 surfaces of the lungs
costal
mediastinal
diaphragmatic
what is in the lung hilum
- bronchi
- pulmonary artery (in front of bronchus)
- superior pulmonary vein (most anterior)
- inferior pulmonary vein (most inferior)
(includes the group of structures that enter/leave the lung hilum)
where is the lung hilum located
on the mediastinal surface of the lung
what is different about the R lung hilum
it has an additional bronchus called eparterial bronchus (above the artery)
R main bronchus is also referred to as the hyparterial bronchus
parts of the pleura
visceral - against the lungs parietal - against the rib cage cupular - covers the apex costal - covers rib surface diaphragmatic mediastinal
nerve supply of pleura
parietal: somatic nerves (IC nerves, phrenic nerves - PAIN SENSITIVE)
visceral: autonomic nerves (T2-5) PAIN INSENSITIVE
where are the pleural reflections and recessess
costomediastinal
costodiaphragmatic (clinically referred to as the costophrenic angle)
when we breathe in the recesses are filled
define pleural reflection
place at which the parietal pleura changes its direction of travel
define pleural recess
the increased space between the layers of pleura occurring at the pleural reflections
surface anatomy of the lungs and pleura
2 IC spaces between bottom of lung and pleura during expiration
e.g. inferior margins of the lung (midclavicular line - rib 6, midaxillary line - rib 8, midscapular line - rib 10)
inferior margins of parietal pleura (rib 8, 10 and 12)
horizontal fissure of R lung follows line of 4th rib anteriorly
oblique fissure begins at T3 spine and follows line of 6th rib anteriorly
what type of epithelium and cartilage is in the trachea
stratified columnar epithelium
hyaline cartilage
the large bronchi is histologically similar to the trachea
compare the wall of the bronchioles to the trachea and bronchi
no cartilage, glands or goblet cells in the walls of the bronchioles compared to the trachea and larger bronchi
epithelium is either columnar or cuboidal
what happens as the tubes become smaller in the lung:
- epithelium becomes flatter (columnar –> cuboidal –> squamous)
- cartilage reduces (rings –> small plates –> complete abscence in bronchioles)
- mucous secreting glands and goblet cells decrease (complete abscence in bronchioles)
