Pulmonary System Flashcards
Types of Pleura in the lungs
Visceral pleura: lines the lungs themselves
Parietal pleura: lines the pulmonary cavities
Pleural cavity
Space between pleura layers. Contains serous pleural fluid lubricating pleural surfaces.
4 parts of the parietal pleura
Costal
Mediastinal
Diaphragmatic
Cervical pleura (cupula)
Suprapleural membrane
Also called sibson fascia
- fibrous extension of endothoracic fascia that reinforces cervical pleura and prevents distortion of superior thoracic aperture.
- attaches to rib 1 and transverse process of C7
Apex of lung
Superior end ascends slightly above 1st rib into the root of the neck
- covered by cervical pleura
Base of lung
Inferior surface of lung resting on the diaphragm.
Right lung has how many lobes and fissures
3 lobes, 2 fissures (oblique and horizontal)
Left lung has how many lobes and fissures
2 lobes, 1 fissure (only oblique)
Main bronchi
Most superior portion of the bronchi tree. Segments off the larynx at the sternal angle.
Right bronchi: shorter and wider with a more vertical pathway
Left bronchi: longer and runs more inferolaterally
- most often the right bronchi is lodged when blockage is possible.
Lobar bronchi (secondary)
2nd branch off the main bronchi
- 2 on the left primary
- 3 on the right primary
Each 2nd branch correlates with a lobe of that respective lung.
Segmental bronchi (tertiary)
3rd branch off lobar bronchi
- contains several branches off the lobar bronchi
- supply bronchopulmonary segments which are the smallest sections of lungs that can be individually incised out.
- 10 in the right
- 8-10 in the left
Levels of bronchioles from largest to smallest
Conducting
Terminal
Respiratory
Alveolar sacs
Found at the ends of respiratory bronchioles.
Unit of respiratory exchange of gases
Right and left pulmonary arteries
Arise from the pulmonary trunk at the level of the sternal angle.
Carry venous blood to the lungs.
- segment into lobar arteries, 1 for each lobe of the respective lungs.
Superior and inferior pulmonary veins
Found on both lungs and named after the lobe they reside in.
Carry oxygen rich blood to the heart.
- right lung also has middle lobe vein
Bronchial arteries
Supply blood to the lung tissues. Arise from the aorta.
Trachea
Inferior portion of the larynx beginning at C4 and running to T4/5.
Supported by C-shaped rings of hyaline cartilage
Trachealis muscle
Smooth muscle within the posterior tracheal wall.
Provides limited constriction of the airway when it contracts.
Carina
T4 ridge of cartilage that signals the splitting into two primary bronchi.
Lymphatic drainage of the lungs
Moves from distal to proximal with proximal being the hilum of the lungs.
- right lung and inferior left lobe of left lung drain into the right lymphatic duct
- superior left lobe of the left lung drain into the thoracic duct
Sympathetic efferent fiber pathways to the lungs
Consists of presynpatic fibers of T1-5 that synapse onto the sympathetic trunk
Postsynpatic fibers leave sympathetic trunk via splanchnic nerves to the pulmonary plexuses
Actions of sympathetic efferent fibers in the lungs
Bronchodilator
Vasoconstriction
Secretory reduction (inhibits alveolar glands of bronchi tree)
Parasympathetic efferent fiber pathways to the lungs
Presynaptic fibers travel via vagus nerves directly to the pulmonary plexuses and synapse on the branches of the bronchial tree
Parasympathetic efferent fiber actions on the lungs
Bronchoconstriction
Vasodilation
Secretomotor (stimulates secretions of alveolar glands)
Visceral afferent fibers
Either reflexive of nociception responses.
Reflexive: take the same path as parasympathetic
Nociceptive: excluding trachea, follow the sympathetic route. (Trachea follows parasympathetic)
Reflexive afferent fibers include what types of stimuli?
Stretch, tactile and chemo and pressure (baro).
Phrenic nerve
Carries both somatic afferent and efferent fibers from C3-5
Somatic efferent fibers: stimulate contraction of diaphragm
Somatic afferent fibers: transmit stimuli from mediastinal and diaphragmatic pleura
Intercostal nerves
Transmit somatic afferent fibers from peripheral regions of the costal pleura
Pulmonary collapse
Caused by penetration of the thoracic wall or surface of lungs
- causes air to be sucked into the pleural cavity via negative pressure, breaking the surface tension adhering visceral to parietal pleura.
- causes lung to collapse and deflate causing major empty space.
Radiographic representation of collapse lung
Elevated diaphragm on the collapsed side.
Reduction of plural cavity
Displacement of the mediastinum towards the collapsed side.
Collapsed lung appears more white surrounded by deeper blackness
Pneumothorax
Hydrothorax
Hemothorax
Air, Fluid, blood filling of the pleural cavity.
Blood usually only occurs via major vessels being torn
Radiological representation of the thoraxes
Lung is collapsed and appears whiter with either black (pneumothorax) or gray (hemothorax or hydrothorax) background
If air and fluid are present in the lung, a sharp horizontal line of different opaqueness will be present.
Pleuritis
Inflammation of pleura.
Distinguishable by crackling, friction like sounds via auscultation of the lungs.
Usually accompanied by sharp pain while breathing, especially on exertion, and increase in overall rate of respiration.
Segmental atelectasis and its radiological appearance
Collapsing of lung segment via blockage of the respective segmental bronchi.
Causes mediastinal shift in radiographs. Can also cause enlarged segments of the lung to counteract lost segment.
Pulmonary embolism
Blockage of a pulmonary artery often seen via a fat globule, air bubble or thrombus from a leg vein.
Can cause acute respiratory distress (complete loss of oxygenated blood usually via embolism)
Can cause pulmonary infarction (necrotic region of lung tissue via hypoxia).
Pleural pain
Parietal pleura irritation can cause referred pain to dermatomes supplied via C1-C5
