Anatomy - Pleural Cavities and Lungs Flashcards
What are the pleurae?
Serous sacs surrounding the lungs
During breathing, what 3 thoracic dimensions vary? What is each due to?
- Vertical: diaphragm2. Lateral: intercostal muscles moving the shafts of the ribs3. Anteroposterior: intercostal muscles moving the sternum
Are the anterior ends of the ribs superior or inferior to the posterior ends?
Inferior
How does the sternum moves when the ribs elevate?
Upward and forward
How does the sternum moves when the ribs depress?
Downward and backward
Level of shaft of ribs compared to anterior and posterior ends?
Slightly inferior
Borders of pleural cavities?
- Superiorly: root of neck 3-4 cm above costal cartilage of rib 1 but not higher than its neck2. Inferiorly: just above the costal margin3. Medially: mediastinum4. Anteriorly: posterior portion of sternum but in the inferior portion the left one does not come as close as the right one because mediastinum bulges to the left
Composition of pleura?
- Single layer of flat mesothelial cells2. Layer of supportive connective tissue
2 types of pleura? Based on what?
Based on location:1. Parietal: associated with walls of pleural cavity2. Visceral: reflected from medial wall onto and adheres to surface of lung
4 parts to the parietal pleura?Describe each.
- Costal: related to ribs and intercostal spaces2. Diaphragmatic: covering diaphragm3. Mediastinal: covering mediastinum4. Cervical pleura: dome shaped lining the cervical extension of the pleural cavity
2 other names for cervical pleura?
- Dome of pleura2. Pleural cupola
What is the suprapleural membrane? What is it attached to? What muscle fibers does it receive?
Dome-like layer of fascia covering the cervical pleura Attached to medial margin of 1st rib and to transverse process of C7Receives scalene muscles from the neck
Can you see visceral pleura on a cadaver?
NOPE
At which point do the visceral and parietal pleurae become continuous?
At the hilum of the lung
Vertebral level of hilum of the lung?
T5 to T7
What is the root of the lung?
The hilum of the lung and the structure it contains
Innervation of parietal pleura? Where would pain be felt for each?
Somatic afferent nerves: 1. Costal: branches of intercostal nerves (pain in thoracic wall)2. Diaphragmatic: phrenic nerves (pain in C3-C5 dermatomes = lateral neck and supraclavicular region of shoulder) and lower intercostal nerves3. Mediastinal: phrenic nerves (pain in C3-C5 dermatomes = lateral neck and supraclavicular region of shoulder)
Describe in painful detail the inferior margin of the parietal pleura.
Margin is just above the costal margin1. Midclavicular line: rib 82. Midaxillary line: rib 103. More laterally: horizontal margin crossing ribs 11 and 12 to reach T12
Innervation of visceral pleura? Where is pain felt?
Autonomic nerves accompanying bronchial vesselsNo pain felt, only stretch
What sensations is the parietal pleura sensitive to?
- Pain2. Touch3. Temperature4. Pressure
What are pleural recesses?
Areas where 2 layers of parietal pleura become opposed
Do the lungs completely fill the pleural cavities? What does this mean?
Nope, not in the anterior or posterior inferior regions BUT these spaces fill during FORCED inspiration => potential spaces where fluid can accumulate
What are the 2 types of pleural recesses? Which are more clinically significant? Which are larger?
- Costomediastinal recesses2. ***Costodiaphragmatic recesses
Describe the costomediastinal recesses. Larger right or left one?
Costal pleura and mediastinal pleura oppose anterior to the heart and inferior to the lungLarger on left side overlying the heart
Describe the costodiaphragmatic recesses.
Costal pleura and diaphragmatic pleura oppose between inferior margin of lung and pleural cavity
When are pleural processes deepest?
After forceful expiration
Describe in painful detail the quiet inspiration inferior margin of the lung.
- Midclavicular line: rib 62. Midaxillary line: rib 83. More laterally: horizontal margin to reach T10
How many pleural recesses total?
4
What is found between the parietal pleura and the ribs?
Thoracic cavity lined with endothoracic fascia
Which lung is bigger?
Right one
Describe the 4 characteristics of each lung.
- Base on diaphragm2. Apex above rib 1 into root of neck3. 3 surfaces3. 3 borders
Describe the 3 surfaces of the lungs.
- Costal surface2. Mediastinal surface against mediastinum anteriorly and vertebral column posteriorly 3. Diaphragmatic surface
Which lung surface contains the hilum?
Mediastinal surface
Describe the 3 borders of the lungs.
- Inferior: sharp and separates base from costal surface2 and 3. Anterior (sharp) and posterior (smooth) borders separate costal surface from mediastinal surface
What is the pulmonary ligament? Functions?
A thin fold of pleura projecting inferiorly from the hilum to the mediastinumFunctions:1. Stabilizes inferior lobe2. Accommodates down and up translocations of root structures during breathing
Location of vagus nerves in relation to roots of lungs?
Posterior
Location of phrenic nerves in relation to roots of lungs?
Anterior
6 contents of roots of lungs? Include positions.
- Pulmonary artery (superior on left and posterior on right)2. 2 pulmonary veins (inferior)3. Main bronchus (posterior on left and branched with the lobar bronchus to the superior lobe and SUPERIOR ON RIGHT)4. Bronchial vessels5. Nerves6. Lymphatics
Number of lobes of right lung?
3
Number of fissures of right lung?
2
What are lung fissures?
Invaginations of visceral pleura separating the lobes
2 fissures of right lung?
- Oblique fissure separating inferior and middle/superior lobes 2. Horizontal fissure separating middle and superior lobes
Location of oblique fissure of right and left lungs in quiet respiration?
Curved line from spinous process of T4 to 4th and 5th intercostal space to rib 6 anteriorly
Location of horizontal fissure of right lung in quiet respiration?
4th intercostal space from sternum to the oblique fissure over rib 5
What do the lung fissures determine clinically?
Where clinicians should listen for lung sounds
Anterior and posterior surface projections of right superior lobe?
Anterior = root of neck to above rib 4 Posterior = root of neck to above rib 6
Anterior and posterior surface projections of right middle lobe?
Anterior = top of 4th rib to medial 6th ribPosterior = top of rib 6 to top of rib 10 medially
Anterior and posterior surface projections of right inferior lobe?
Anterior = laterally over rib 6 and 5th and 6th intercostal spaces (around nipple)Posterior = none
6 mediastinal structures in contact with medial surface of right lung? Which form impressions on the mediastinal surface of the right lung? Structure not part of mediastinum that also forms an impression?
- Heart2. IVC3. SVC4. Azygos vein* (impression from arch)5. Esophagus6. Right brachiocephalic vein**+ 1st rib
Number of lobes of left lung?
2
Number of fissures of left lung?
1
Which is more oblique: the right or left fissure?
Left one
Anterior and posterior surface projections of left superior lobe?
Anterior = root of neck to above 4th rib and then inverse C-shape to above rib 6 Posterior = root of neck to above rib 6
Anterior and posterior surface projections of left inferior lobe?
Anterior = over lateral 6th rib and 5th and 6th intercostal spaces above and below (around nipple) Posterior = top of rib 6 to top of rib 10 medially
Which lung has a notched mediastinal surface? Why? What is this called? Where is it?
Left lung due to heart’s projection = cardiac notch on superior lobe at the anterior border
What is the lingula of the left lung? Function?
Tongue-like extension of the anterior border of the lower portion of the superior lobe projecting over the heart anteriorly and bordering the left lower border of the heartFunction: increases gas exchange surface area of left lung
5 mediastinal structures in contact with medial surface of left lung? Which 3 form impressions on the mediastinal surface of the left lung?
- Heart2. Aortic arch3. Thoracic aorta4. Esophagus5. Left brachiocephalic vein***
Lymphatic drainage of lungs?
Tracheobronchial nodes
Where are tracheobronchial lymph nodes located?
Around root of lobar and main bronchi and alongside trachea
Pathway of lung lymphatic drainage?
Within the lung => through hilum => posterior mediastinum => tracheobronchial nodes => lymphatic vessels in the superior mediastinum anterior to the brachiocephalic veins that also drain lymph from parasternal and brachiocephalic nodes => right and left bronchomediastinal trunks => veins at base of neck OR right lymphatic duct/thoracic duct
Lung innervation?
Pulmonary plexus with branches from sympathetic trunks and vagus nerves lying anteriorly and posteriorly to tracheal bifurcation (anterior smaller than posterior)
Vertebral borders of trachea?
C6 to T4/T5
What is the carina?
Most inferior tracheal cartilaginous ring that is hook-shaped projecting backwards
Do inhaled foreign bodies lodge more frequently in the right or left main bronchi? Why?
Right one because it is wider and takes a more vertical course through the root of the lung than the left one AND because the carina tends to block aspirated objects from going in the direction of the left primary bronchus
What airway generation supplies per lobe?
Lobar bronchi
Other name for segmental bronchi?
Tertiary bronchi
What do segmental bronchi supply?
Bronchopulmonary segments
What are bronchopulmonary segments?
Area of lung supplied by a segmental bronchus and its accompanying pulmonary artery branch
Shape of bronchopulmonary segments?
Irregular cones with apex at origin of segmental bronchus and base projecting peripherally onto surface of the lung
Smallest area of lung that can be isolated and removed without affecting adjacent regions? Why?
Bronchopulmonary segment because it is functionally independent
How many bronchopulmonary segments in each lung?
10, but some of them fuse in the left lung
Where are pulmonary veins found in the lungs?
Between margins of bronchiopulmonary segments
Where does the bifurcation of the pulmonary trunk take place?
Sternal angle to the left of the bifurcation of the trachea
Which pulmonary artery is longer: left or right one?
Right one
Position of right pulmonary artery.
- Anterior to trachea and right main bronchus2. Posterior to ascending aorta, SVC, and upper pulmonary vein
Position of left pulmonary artery.
- Anterior to descending aorta 2. Posterior to superior pulmonary vein3. Superior to left main bronchus
Does the left pulmonary artery only branch within the lung?
YES
Does the right pulmonary artery only branch within the lung?
TBD
Do bronchial arteries and veins interconnect with branches of pulmonary arteries and veins within the lung?
YUP
List the 3 bronchial arteries and what artery they arise from.
- Right bronchial artery from the 3rd posterior intercostal artery or superior left bronchial artery2. Superior left bronchial artery from the anterior surface of the thoracic aorta (at T5)3. Inferior left bronchial artery from the anterior surface of the thoracic aorta (inferior to left bronchus)
On what surface of the bronchi do the bronchial arteries run?
Posterior
Where do the bronchial veins drain into?
- Pulmonary veins2. Left atrium3. Azygos vein on right4. Superior intercostal vein on left 5. Hemiazygos vein on left
When is a lung cancer inoperable? What is the treatment then?
When the tumor has invaded structures in the mediastinum or the pleurae or has metastasizedTreatment: radiotherapy and chemotherapy
Through what lymph nodes does lung cancer spread?
Lymph nodes within hila, mediastinum, and root of the neck
Imaging techniques to assess spread of metastasized lung cancer?
Radiography, CT, MRI, or PET
Do lungs appear with black spots on their visceral pleura normally?
YUP because of pollution
How to differentiate the bronchus in the root of the lung?
It is WHITER and THICKER
Where are lymph nodes found at the root of the lung?
Inferiorly and anteriorly
Location of azygos vein in relation to the right lung hilum?
Superior
Location of right brachiocephalic vein in relation to the right lung hilum?
Anterior
Location of SVC in relation to the right lung hilum?
Anterior and inferior
Location of esophagus in relation to the right lung hilum?
Posterior
What does the parietal pleura look like on a cadaver?
Transparent/whitish
Stethoscope placement to listen to apex of lung?
Right above medial clavicle
Stethoscope placement to listen to middle lobe of right lung?
Middle of 4th intercostal space
Stethoscope placement to listen to superior lobe of lung?
Middle of 2nd intercostal space
Stethoscope placement to listen to inferior lobe of lung?
Lateral portion of 6th intercostal space
Which intercostal spaces to the left of the sternum are not left lung?
4-6th intercostal spaces are the heart!
Posterior surface projection of the top of the oblique fissure?
T4
Surface projection of left costomediastinal recess?
4th and 5th ICS further than 3.5 inches from midline
Anterior and posterior surface projections of left and right costodiaphragmatic recesses?
Anterior = medial 6th ICS to lateral 8th ICSPosterior = T10 to T12
How does the parietal pleural adhere to the endothoracic fascia? How does this contribute to respiration?
By surface tensionDuring inspiration, when the thoracic cage expands, the parietal pleura expands, which allows the lungs to expand also
What lung lobes comprise most of the anterior surface of the thorax?
Superior lobe of both lungs + middle lobe of right lung
What is the right main bronchus referred to? Why?
Eparterial bronchus because it is located superior to the right pulmonary artery in the root of the right lung
Technically are the lungs within the pleural cavity?
Although clinically the lungs are often considered to be within the pleural cavity, technically they are outside the pleural cavity
What is a hemothorax?
Blood in pleural cavity
What are lines of pleural reflection?
Places where pleura turns to change from one surface to another
Other name for costodiaphragmatic recess?
Costophrenic recess
Procedure to drain fluid out of pleural cavity? What must first be done? Where is it typically performed?
Pleural tap = thoracocentesis First, anesthetize the rib by infiltration to rib and space above and below because the periosteum is extremely sensitive Lower ICS 4 or 5 between midaxillary lines and anterior axillary lines
What muscles can help the diaphragm during forced expiration?
Abdominal muscles
Right lung bronchi: once the right upper lobar bronchus has branched off, what do you call the remaining right bronchus?
Interlobar bronchus or bronchus intermedius
If veins are dilated on both sides of the neck, what would this indicate regarding the location of lung cancer?
Near SVC in right lung
If patient is having difficulty breathing, what would this indicate regarding the location of lung cancer?
Phrenic nerve is affected
2 most common causes of a pneumothorax?
- Rib fractures2. Positive pressure ventilation lung damage
Diseases associated with pleural effusion?
- Lung infection2. Cancer3. Abdominal sepsis
Cause of hemopneumothorax?
Severe chest trauma
What do you risk if you insert a needle below the 5th ICS?
Placing needle in liver or spleen (L or R)
Why are upper lobe pneumonias unusual?
Because most patients develop gravity-dependent infections
What 2 infections are common in upper and middle lung lobes?
- Tuberculosis (bacteria)2. Histoplasmosis (fungus living in soil)
Auscultation sign of pneumonia?
Decreased breath sounds which are hoarse in nature = bronchial breathing
Percussion sign of pneumonia?
Dull percussion sound
How do the lungs become surrounded by pleura?
During development they grow out of the mediastinum
What lies on each side of the superior thoracic aperture?
Axillary inlets
What is each axillary inlet formed by?
- Superior margin of scapula posteriorly2. Clavicle anteriorly3. Lateral margin of rib 1 medially4. Medial margin of coracoid process superiorly 5. Triangular opening inferiorly
