Lower Respiratory Tract lecture Flashcards
Parietal Pleura
- lines pleural cavity, several names for the surfaces it covers
- innervated by intercostal nerves and phrenic nerves
- forms pulmonary ligament
Costal Pleura
Part of parietal pleura, attached to ribs and intercostal spaces
Mediastinal pleura
part of parietal pleura, attached to mediastinum
Diaphragmatic pleura
part of parietal pleura,adheres to superior surface of respiratory diaphragm
Cervical pleura
part of parietal pleura,lines pleural cavity above level of 1st ribs, in root of neck
Visceral Pleura:
covers surfaces of lungs, insensitive to pain
Connecting Layer
- surrounds roots of lungs like a sleeve
- covers structures that pass into lungs (bronchi, nerves, lymphatics, etc)
Vertical Reflection
where costal and mediastinal pleurae become continuous posteriorly
Sternal Reflection
costal and mediastina pleurae become continuous anteriorly
Costal Reflection
costal and diaphragmatic pleurae become continuous inferiorly
Describe the lines of reflection of the parietal pleura.
Vertical, sternal, costal reflection
pleural recesses
- occur where two layers of parietal pleura form an acute angle,in direct contact with each other
- lungs not in these recesses normally, but with certain infections can be filled with pus
Right Costodiaphragmatic Recess
located laterally along costal reflection, allow lungs to be pulled during inspiration
Left Costodiaphragmatic Recess
located laterally along costal reflection, allow lungs to be pulled during inspiration
Left Costomediastinal Recess
located anteriorly along sternal reflection, where costal and mediastinal pleurae meet
Pleural Cavities
- Spaces between two pleural layers
- contains pleural fluid which is secreted by the pleural membranes
Pleural Sacs
- Beneath visceral pleura
- contains lungs
Intercostal nerves
supply fibers for pain and irritation to costal pleura in addition to supplying the periphery of the respiratory diaphragm
Phrenic nerves
supply fibers for pain and irritation to the mediastinal pleura and the diaphragmatic pleura.
lower respiratory tract components?
- Begins with trachea, main stem bronchi, bronchial tubes, and lungs
- Trachea, bronchi, bronchial tubes contain ciliated pseudostratified columnar epithelium
- Cilia move up mucous toward laryngopharynx, where it can be coughed up
course of the trachea from the neck into the superior mediastinum
- continuous with larynx
- extends from C6 vertebrae to sternal angle at same level as T4
- transverse thoracic plane passes through sternal angle to intersect intervertebral disc between T4 and T5, bifurcates trachea into two main bronchi
Describe the composition of the trachea
- 20 “U shaped” cartilage rings, dont go all the way around trachea
- smooth muscle: elastic posterior wall of trachea, next to esophagus
- mucous glands keep surface of epithelium covered with mucous
Arteries of trachea
superior and inferior thyroid arteries
Veins of trachea
superior, middle and inferior thyroid veins
Right main bronchi
Larger diameter, more vertical, shorter, 3 lobar bronchi to lungs, branches into 10 segmental bronchi
-runs under arch of azygos vein
Left main bronchi
Small diameter, less vertical, longer, 2 lobar bronchi to lungs, 8 segmental bronchi
-runs under left pulmonary artery
Tertiary bronchi
go to bronchopulmonary segments
How many segmental bronchi do right and left lungs have?
Right lung has 10 segmental bronchi
Left lung has 8 segmental bronchi
Terminal bronchioles
branches of segmental bronchi
Respiratory bronchioles
contain alveoli
Alveoli
single cell in thickness, surrounded by dense capillary network
Blood Supply
Three bronchial arteries from descending aorta, supply bronchial tubes but not alveoli, not a part of pulmonary circulation
Where do bronchial veins drain?
bronchial veins drain to to azygos vein which are tributaries of vena cava
Oblique Fissures
- in left lung: divides into upper and lower lobes
- in right lung: divides middle from lower lobe and upper lobe from lower lobe
Horizontal Fissure
-only in right lung, separated upper lobe from lower lobe
Cardiac Notch
upper lobe of left lung, adjacent to heart
Lingula
shaped like tongue, upper lobe of left lung, next to cardiac notch
Apex
area of lungs above the first ribs; also known as the cupola
Base
area of lungs adjacent to the respiratory diaphragm.
Hilum
contains structures entering and exiting the lungs(ex: bronchi)
Pulmonary trunk
emerges from right ventricle
Pulmonary arteries (right and left)
have branching pattern similar to bronchi.
Alveolar capillary network
functional part of the pulmonary circulation; provides for exchange of blood gases with air in the alveoli. The total surface area of this capillary network must be equal in size to all of the combined capillaries in all the organs in the body
Pulmonary veins
collect blood from alveoli and return it to the left atrium
Sensory (GVA neurons)
contained in vagus nerve (CN X)
Stretch receptors
contained in alveoli and smooth muscle.
Irritant receptors
located in respiratory epithelium.
Tactile receptors
cough reflex
Baroreceptors
in pulmonary arteries
Chemoreceptors
in pulmonary veins (detect blood gases)
Motor (GVE neurons)
autonomic fibers contained in pulmonary nerve plexus
Sympathetic (post-ganglionic) nerve fibers
to smooth muscle and glands; function to inhibit glandular secretion, induce vasoconstriction of bronchial vessels, and dilate bronchial tubes
Parasympathetic nerve fibers
to smooth muscle and glands; function to increase glandular secretion, induce vasodilation of bronchial vessels, and constrict bronchial tubes
Pre-ganglionic parasympathetic fibers
are contributed to the pulmonary nerve plexus by the vagal nerves (CN X). These fibers synapse with post-ganglionic parasympathetic fibers on the surfaces of bronchial tubes and bronchial vessels
Superficial plexus
lies deep to the visceral pleura; drains lymph from the visceral pleura and lung parenchyma to the bronchopulmonary lymph nodes in the hilum
Deep plexus
located in the substance of the bronchi; drains lymph from the bronchi to pulmonary lymph nodes near the hilum and then goes to the bronchopulmonary nodes in the hilum
- Pulmonary nodes
located in lungs at the bifurcations of larger bronchi
- Bronchopulmonary (hilar) nodes
located in the hilum
- Tracheobronchial nodes
located at the bifurcation of the trachea
- Tracheal nodes
found on the lateral surfaces of the trachea
Right bronchomediastinal lymph trunk
drains lymph from the right side of the trachea to the right lymphatic duct
Left bronchomediastinal lymph trunk
drains lymph from the left side of the trachea to the thoracic duct.
Lung Cancer
Can derive from actual lung tissue, or from the Bronchi (Bronchogenic
Carcinoma). Lung cancer can involve the Phrenic N., Vagus N. and Recurrent Laryngeal N. due
to the proximity of those nerves to the Lungs. Treatment can include removal of a Lung
(Pneumonectomy), a lobe of a lung (Lobectomy) or a specific Bronchopulmonary Segment
(Segmentectomy) through a procedure called Lung Resection
Pleuritis (Pleurisy) is an inflammation of the Pleura
producing a roughness on the lungs
making breathing difficult
Pulmonary Collapse
occurs when enough air enters the Pleural Cavity to break the surface
tension between the two layers of Pleura. The elasticity of the Lungs causes them to collapse
Pneumothorax
Entry of air into the Pleural Cavity from a penetrating wound to the
Thoracic Wall or a rupture of a pulmonary lesion into the pleural cavity, which results in a
collapse of the lung
Hydrothorax
Accumulation of excess fluid in the Pleural Cavity, usually the result of fluid
escape into the Pleural Cavity, or Pleural Effusion
Hemothorax
Accumulation of blood in the Pleural cavity, usually the result of a chest
wound, usually the result of laceration of an Intercostal vessel or Internal Thoracic vessel rather
than laceration of the lung.
Bronchial Asthma
widespread narrowing of the airways produced by contraction of
smooth muscle, edema of the mucosa and mucus in the lumen of the Bronchi and Bronchioles
Bronchoscopy
Insertion of a Bronchoscope into the trachea to visualize the Main Bronchi
bronchopulmonary segment
- anatomic and functional subunit of lungs
- portion of lung supplied by each segmental bronchus and segmental artery
