Intro to Pulm- Lecture Flashcards
The conducting zone begins with the _ and ends with the _
The conducting zone begins with the trachea and ends with the terminal bronchioles
The respiratory zone begins with the _ and ends with the _
The respiratory zone begins with the respiratory bronchioles and ends with the alveolar sacs
The components of the thoracic skeleton include:
The components of the thoracic skeleton include:
1. Sternum
2. Twelve ribs, costal cartilages
3. Twelve thoracic vertebrae and IV discs
The sternum is composed of three parts the _ , _ , and _
The sternum is composed of three parts the manubrium , body , and xiphoid process
The _ is the articulation between the manubrium and the body of the sternum
The Sternal angle (Angle of Louis ) is the articulation between the manubrium and the body of the sternum
The sternal angle marks the location of the _ rib/ costal cartilage
The sternal angle marks the location of the 2nd rib/ costal cartilage
The Angle of Louis is an important landmark because the _ sits just posterior to the sternal angle
The Angle of Louis is an important landmark because the aortic arch sits just posterior to the sternal angle
What is the main function of the ribs?
The function of the ribs is to provide protection and assist with respiration
True ribs are ribs that _
True ribs are ribs that articulate directly with the sternum via their own costal cartilage
* Ribs 1-7
False ribs are ribs that _
False ribs are ribs that indirectly articulate with the sternum via costal cartilage of the superior rib
* Ribs 8-10
Floating ribs are ribs that _
Floating ribs are ribs that do not articulate with the sternum and end in the posterior abdominal wall
* 11 and 12
What is the costal groove?
The costal groove is a shallow groove located inferiorly for the passage of neurovascular structures
1. Intercostal vein
2. Intercostal artery
3. Intercostal nerve
The most common site of rib fracture is at the (head / costal angle / shaft)
The most common site of rib fracture is at the shaft at the costal groove
* Vein, artery, nerve run here so rib fractures can cause some bleeding
External intercostal muscles run in _ direction
External intercostal muscles run inferomedially
* They assist with inspiration
Internal intercostal muscles run in _ direction
Internal intercostal muscles run “down and out” (laterally)
* They assist with forced expiration
(Internal/ external) intercostals run at about 90 degree angle from the ribs
Internal intercostals run at about 90 degree angle from the ribs
Intercostal muscles are innervated by _
Intercostal muscles are innervated by intercostal nerves that course in the costal grooves
The diaphragm, the chief muscle of respiration is innervated by the _ nerves
The diaphragm, the chief muscle of respiration is innervated by the phrenic nerves
” _ , _ , _ keeps the diaphragm alive”
“C3 , C4 , C5 keeps the diaphragm alive”
The phrenic nerve provides motor function to the _
The phrenic nerve provides motor function to the diaphragm
The phrenic nerve provides sensory innervation to the _
The phrenic nerve provides motor function to the innervates the central part of the diaphragm, the fibrous pericardium and the mediastinal part of the parietal pleura
Pain from the diaphragm often refers to the _ area
Pain from the diaphragm often refers to the shoulder area (dermatomes C3, C4, C5)
The diaphragm muscle originates around the periphery and converges onto the aponeurotic _
The diaphragm muscle originates around the periphery and converges onto the aponeurotic central tendon of the diaphragm
The crura of the diaphragm are musculotendinous bundles that arise from _ vertebrae
The crura of the diaphragm are musculotendinous bundles that arise from L1-L4
There are several apertures (holes) in the diaphragm that allow important structures to pass like _
There are several apertures (holes) in the diaphragm that allow important structures to pass like the IVC, esophagus, aorta
The inferior vena cava passes through the diaphragm at the _ aperture; at vertebral level _
The inferior vena cava passes through the diaphragm at the caval opening; at vertebral level T8
The esophagus passes through the diaphragm at the _ aperture; at vertebral level _
The esophagus passes through the diaphragm at the esophageal hiatus; at vertebral level T10
The aorta passes through the diaphragm at the _ aperture; at vertebral level _
The aorta passes through the diaphragm at the aortic hiatus; at vertebral level T12
The vagus nerve passes through the diaphragm at the _ aperture along with the _
The vagus nerve passes through the diaphragm at the esophageal hiatus aperture along with the esophagus (T10 level)
Of the structures that pass through the diaphragm, _ actually runs behind it and is not affected by movement of the diaphragm
Of the structures that pass through the diaphragm, the aorta actually runs behind it and is not affected by movement of the diaphragm
The diaphragm becomes more “dome-shaped” on (inspiration/ expiration)
The diaphragm becomes more “dome-shaped” on expiration
The visceral layer of the lung pleura adheres to the _
The visceral layer of the lung pleura adheres to the surface of the lung and extends into the lung fissures
The parietal layer of the lung pleura lines the _
The parietal layer of the lung pleura lines the thoracic cavity, superior diaphragm, mediastinum
The parietal pleura of the lungs involves 4 “regions”
- Costal portion
- Cervical portion
- Diaphragmatic portion
- Mediastinal portion
The visceral and parietal layers of the lung pleura are continuous with one another at the _
The visceral and parietal layers of the lung pleura are continuous with one another at the root of the lung
* The pleural cavity is the space between the two layers of the lung (acts like a vacuum)
The pleural cavity is a potential space that is filled with a thin layer of _ that serves to _
The pleural cavity is a potential space that is filled with a thin layer of serous fluid that serves to lubricate and decrease surface tension
The (visceral/ parietal) pleura is innervated by somatic sensory nerves
The parietal pleura is innervated by somatic sensory nerves
* Ex: intercostal nerves
* It is very sensitive to pain
* Pleuritic chest pain is really from the parietal pleura
The visceral pleura is innervated by _ nerves and is relatively (sensitive/ insensitive) to pain
The visceral pleura is innervated by visceral sensory nerves and is relatively insensitive to pain
The lung has two recesses _ and _ that accommodate the explansion of the lung during inspiration
The lung has two recesses costodiaphragmatic recess and costomediamediastinal recess that accommodate the explansion of the lung during inspiration
* The lung and its visceral pleura are somewhat smaller than the wall of the pulmonary cavity and its parietal layer
The _ recess is the location where the diaphragmatic pleura meets the costal pleura
The costodiaphragmatic recess is the location where the diaphragmatic pleura meets the costal pleura
The costomediastinal recess forms between the _ and _
The costomediastinal recess forms between the pericardial sac and sternum
The _ is the lowest, most dependent position in the pleural cavity; fluid tends to accumulate here
The costodiaphragmatic recess is the lowest, most dependent position in the pleural cavity; fluid tends to accumulate here
The distal end of the trachea, called the _ , branches into right and left primary bronchi
The distal end of the trachea, called the carina , branches into right and left primary bronchi
The (right/left) bronchi is wider and more vertical
The right bronchi is wider and more vertical
* This is why foreign objects tend to obstruct the right lung
The primary bronchi continue to divide and branch into the _
The primary bronchi continue to divide and branch into the bronchial tree
We call the secondary bronchi the _ bronchi
We call the secondary bronchi the lobar bronchi
* Because each lobar bronchi enters a specific lobe of the respective lung
We call tertiary bronchi the _ bronchi
We call tertiary bronchi the segmental bronchi
* Each segmental bronchi branches off the lobar and enters a bronchopulmonary segment
The right lung has _ lobar bronchi and the left lung has _
The right lung has three lobar bronchi and the left lung has two
(True/ False) All bronchi have cartilage
True; All bronchi have cartilage
* Helps to maintain patency
The smallest bronchi give rise to _ which do not have cartilage
The smallest bronchi give rise to bronchioles which do not have cartilage
* Bronchioles are held open by the elasticity of the lung tissue
_ represent the last branch of the conducting system
Terminal bronchioles represent the last branch of the conducting system
* These give rise to the respiratory bronchioles and alveoli where the gas exchange occurs
Gas exchange occurs in the _
Gas exchange occurs in the respiratory bronchioles and alveoli
The lung is subdivided into discrete pyramidal-shaped units called _ that function independently as respiratory units
The lung is subdivided into discrete pyramidal-shaped units called bronchopulmonary segments that function independently as respiratory units
There are _ bronchopulmonary segments in the right lung and _ in the left lung
There are 10 bronchopulmonary segments in the right lung and 8 in the left lung
Each bronchopulmonary segment is supplied independently by a _ bronchus
Each bronchopulmonary segment is supplied independently by a segmental bronchus
* Each is also supplied by a segmental branch of the pulmonary artery
Each lung recieves _ pulmonary artery and returns blood via _ pulmonary veins
Each lung recieves one pulmonary artery and returns blood via two pulmonary veins (superior and inferior)
The _ arteries are the ones that actually vascularize the tissues of the lung; they arise off of the thoracic aorta
The bronchial arteries are the ones that actually vascularize the tissues of the lung; they arise off of the thoracic aorta
* They follow the bronchi into the lung tissue
The mediastinal surface of each lung contains a _ region where vessels, nerves, and bronchi transverse
The mediastinal surface of each lung contains a hilum region where vessels, nerves, and bronchi transverse
* Specifically: pulmonary artery, pulmonary veins, primary bronchus, hilary lymph nodes, bronchial vessels, autonomic nerves
The lungs and the bronchial tree receive innervation via the _
The lungs and the bronchial tree receive innervation via the pulmonary plexus (combination of parasympathetic and sympathetic nerves)
The parasympathetic nerves originate at the _ and travel via the _ nerve to the pulmonary plexus
The parasympathetic nerves originate at the medulla and travel via the vagus nerve to the pulmonary plexus
The sympathetic nerves originate in the _ and travel to the pulmonary plexus to cause:
The sympathetic nerves originate in the upper thoracic spinal cord segments and travel to the pulmonary plexus to cause: bronchodilation, inhibit glandular secretion, vasoconstriction
Moving down the respiratory tract, histology findings _ , _ , _ , and _ tend to decrease
Moving down the respiratory tract, cartilage , glands , ciliated cells , and goblet cells tend to decrease
Moving down the respiratory tract, the amount of _ increases
Moving down the respiratory tract, the amount of smooth muscle increases
Describe the 4 epithelium transitions down the respiratory tract
- Pseudostratified columnar
- Simple columnar
- Simple cuboidal
- Simple squamous
What type of epithelium is this?
Pseudostratified ciliated columnar epithelium
What is the function of these cells?
Goblet cells: secrete mucus precursor droplets into epithelial surface to trap inhaled particles
What is this structure?
Bronchus
* We see goblet cells, respiratory epithelium
* Smooth muscle
* Discontinuous cartilage
What is the function of this structure?
Terminal bronchiole: conducts air
* We see simple columnar epithelium
* Smooth muscle
* No cartilage
* Alveoli can be seen
What is the function of this cell?
Dust cell: removes inhaled dust and bacteria by phagocytosis
* We are in the respiratory bronchiole
What is the structure?
Alveolus
How many cell membranes does CO2 molecule have to travel from hemoglobin in the RBC to the alveolus for exhalation?
- Erythrocyte membrane
- Endothelial cell membrane
- Across the basement membrane
- Across the basement membrane
- Across the type I pneumocyte
What is the purpose of the cell shown?
Type II pneumocyte
* Synthesizes pulmonary surfactant
* Divides and regenerates type I and II pneumocytes
* Contains lamellar bodies
* Is located at septal intersections (corners)
Central chemoreceptors respond only to changes in _
Central chemoreceptors respond only to changes in CO2 (indirectly)
The alveolar pressure at the end of inspiration is _ in a healthy lung
The alveolar pressure at the end of inspiration is 0 cmH2O in a healthy lung
In healthy lungs, intrapleural pressure is always _
In healthy lungs, intrapleural pressure is always negative
In healthy lungs, transpulmonary pressure is always _
In healthy lungs, transpulmonary pressure is always positive
What happens to the intrapleural pressure during a pneumothorax?
Intrapleural pressure is no longer negative
* Transpulmonary pressure becomes negative –> collapses lung
Minute ventilation equation
VE = Tidal volume (Vt) x Respiratory rate (RR)
Alveolar ventilation equation
Va = (Vt - dead space ventilation) x Respiratory rate
Anatomic dead space is _
Anatomic dead space is portion of minute ventilation that fills conducting airways where gas exchange cannot occur
Alveolar dead space is _
Alveolar dead space is portion of minute ventilation that fills alveoli with insufficient blood flow
* This is usually minimal in healthy lungs
_ is the sum of anatomic and alveolar dead space
Physiologic dead space is the sum of anatomic and alveolar dead space
_ law of partial pressures say that the total pressure of gases is the sum of the pressure exerted by each gas
Dalton’s law of partial pressures say that the total pressure of gases is the sum of the pressure exerted by each gas
What is the diffusion path for O2?
1) liquid/surfactant
2) epithelium
3) lung interstitium
4) endothelium
5) blood plasma
6) erythrocyte plasma
membrane
7) chemical combination
w/ hemoglobin
Diffusion of gas across the respiratory membrane is proportional to _ and inversely proportional to _
Diffusion of gas across the respiratory membrane is proportional to surface area, pressure gradient, permeability and inversely proportional to barrier thickness
According to LaPlace, the pressure inside (smaller/ larger) bubbles must be greater than the pressure in larger bubbles to support the higher surface tension
According to LaPlace, the pressure inside smaller bubbles must be greater than the pressure in larger bubbles to support the higher surface tension
Due to the higher pressure inside a smaller alveolus, smaller alveoli have the tendency to collapse into larger ones –> this is bad because it _
Due to the higher pressure inside a smaller alveolus, smaller alveoli have the tendency to collapse into larger ones –> this is bad because it decreases surface area available for gas exchange
* Prevent this from happening with surfactant
_ makes it possible for alveoli of different radii to coexist and be stable at low lung volumes
Surfactant makes it possible for alveoli of different radii to coexist and be stable at low lung volumes
* Made by type II alveolar cells
* Lines the liquid interface
* Reduces the surface tension
What happens to babies with surfactant deficient lungs?
Their lungs are difficult to inflate and tend to collapse at end-expiration
Rank the partial pressure of oxygen along its path from the air –> tissues
Atmosphere
Alveoli
Arterial blood
Systemic capillary
Mitochondria
Alveolar gas equation
In healthy lungs, a normal A-a difference is _
In healthy lungs, a normal A-a difference is 10-20 mmHg
Airflow equation
Q = ∆P / R
However, resistance depends on flow pattern and radius which is not constant
Airflow in a tube (like the lungs) will be fastest in the _
Airflow in a tube (like the lungs) will be fastest in the center
* The interaction of gas with the tube wall consumes energy and decreases speed
If you double the pressure gradient, airflow rate should also double in _ flow
If you double the pressure gradient, airflow rate should also double in laminar flow
* Flow rate will be less than doubled in turbulent airflow
In the lungs, airflow is turbulent in the _
In the lungs, airflow is turbulent in the trachea + mainstem bronchi
In the lungs, airflow is laminar in the _
In the lungs, airflow is laminar in the small airways
* As the aggregate cross-sectional area increases flow velocity decreases to the point of becoming very slow in the distal lung
In most of the bronchial tree of the lungs, airflow is _
In most of the bronchial tree of the lungs, airflow is “transitional”
* This is mixed flow- an intermediate state with elements of both laminar and turbulent flow
The most important parameter for determing air flow is _ according to Pousielle’s law
The most important parameter for determing air flow is radius according to Pousielle’s law
* Resistance is inversely proportional to the 4th power of the radius
Airway resistance (increase/ decreases) as you go distally in the lung towards the alveoli
Airway resistance decreases as you go distally in the lung towards the alveoli
* Due to the increase in the aggregate cross-sectional airway
* In healthy lungs, small airways only contribute slightly to the overall lung resistance; this is a “silent zone”
Resistance to airflow is dynamic; as expiration proceeds, resistance _ and as inspiration proceeds, resistance _
Resistance to airflow is dynamic; as expiration proceeds, resistance increases and as inspiration proceeds, resistance decreases
* This has to do with the change in lung volume
_ is the change in lung volume for a given change in pressure
Compliance is the change in lung volume for a given change in pressure
* It is related to elastic recoil and surface tension
Lung compliance is determined by _ and _
Lung compliance is determined by elastic recoil and surface tension
* Both elastic recoil and surface tension are collapsing forces
A large change in volume with a small change in pressure is (high/ low) compliance
A large change in volume with a small change in pressure is high compliance
* A highly compliant lung is floppy and expands easily
A small change in volume with a large change in pressure is (high/ low) compliance
A small change in volume with a large change in pressure is low compliance
* A lung with high elastance is stiff and takes more work to expand
The pressure-volume relationship (compliance) is different for inspiration and expiration; this describes _
The pressure-volume relationship (compliance) is different for inspiration and expiration; this describes hysteresis
* Compliance is higher during expiration
Complaince is _ during expiration than inspiration due to _
Complaince is higher during expiration than inspiration due to surface tension at the liquid-air interface
A saline filled alveolus does not experience hysteresis because _
A saline filled alveolus does not experience hysteresis because saline removes surface tension
* No air-water interactions, only water-water
Draw pressure-volume loop of emphysema
Draw pressure-volume loop of fibrosis
The pulmonary circulation handles the same volume of blood as the systemic circulation; but at a (lower/higher) pressure
The pulmonary circulation handles the same volume of blood as the systemic circulation; but at a lower pressure
* Blood does not have to go as far so it stays at a low pressure
* Low pressure also helps prevent fluid extravasation
The pulmonary arterioles have _ smooth muscle, _ resistance and _ compliance
The pulmonary arterioles have little smooth muscle, low resistance and high compliance
* There are numerous pulmonary arterioles; they are short, thin, and lack auto-regulation
The pulmonary capillaries are not buffered from the arterial pressure; they are highly compliant and also uniquely susceptible to _
The pulmonary capillaries are not buffered from the arterial pressure; they are highly compliant and also uniquely susceptible to alveolar air pressure
Pulmonary arterioles _ in response to low alveolar PO2
Pulmonary arterioles vasoconstrict in response to low alveolar PO2
* Also in response to pH and circulating mediators
* This is an attempt to decrease blood flow to match the decreased O2 in the alveoli
* Preserves V/Q matching
Hypoxia may constrict the pulmonary vasculature by _ the K+ channels
Hypoxia may constrict the pulmonary vasculature by closing the K+ channels –> depolarizes the membrane –> opens Ca2+ channels –> constriction
Lung volumes affect PVR; at low lung volume pulmonary vascular resistance is _ ; at high lung volumes the PVR is _
Lung volumes affect PVR; at low lung volume pulmonary vascular resistance is increased by the collapsed lung ; at high lung volumes the PVR is increased by the inflated lungs compressing the vessels
At low lung volumes, we get compression of _
At low lung volumes, we get compression of larger vessels
At high lung volumes, we get compression of _
At high lung volumes, we get compression of smaller vessels
Ventilation (flow of air per minute) is driven by _
Ventilation (flow of air per minute) is driven by the difference between atmospheric and alveolar pressure
Perfusion (flow of blood per minute) is determined by _
Perfusion (flow of blood per minute) is determined by pulmonary arterial pressure, pulmonary venous pressure, and alveolar pressure
* Alveolar pressure is a factor because alveoli can expand and compress vessels
An expanded alveolus with low ventilation and perfusion is found in _ zone of the lung
An expanded alveolus with low ventilation and perfusion is found in Zone 1 (apex) of the lung
A normal sized alevolus with moderate ventilation and perfusion is found in _ zone of the lung
A normal sized alevolus with moderate ventilation and perfusion is found in Zone 2 (middle) of the lung
A small alveolus with high ventilation and perfusion is found in _ zone of the lung
A small alveolus with high ventilation and perfusion is found in Zone 3 (base) of the lung
The highest V/Q ratio is found in _ zone of the lung
The highest V/Q ratio is found in zone 1 (apex) of the lung
The lowest V/Q ratio is found in _ zone of the lung
The lowest V/Q ratio is found in Zone 3 (base) of the lung
Relatively more air goes to the _ region of the lung due to _
Relatively more air goes to the base of the lung due to gravity
Alveoli at the _ of the lung are most compliant
Alveoli at the base of the lung are most compliant
* They are smaller and more compliant
* Alevoli at the apex, on the other hand, are already distended and so less compliant
The alveoli at the apex of the lung are held open by _
The alveoli at the apex of the lung are held open by the more negative intrapleural pressure
Rank the alveolar, arterial, and venous pressure in zone 1
PA > Pa > Pv
Rank the alveolar, arterial, and venous pressure in zone 2
Pa > PA > Pv
Rank the alveolar, arterial, and venous pressure in zone 3
Pa > Pv > PA
V/Q > 1 in _ zone of the lung
V/Q > 1 in zone 1 of the lung
V/Q = 1 in _ zone of the lung
V/Q = 1 in zone 2 of the lung
V/Q < 1 in _ zone of the lung
V/Q < 1 in zone 3 of the lung
Hypoxia is defined as oxygen < _ mm Hg
Hypoxia is defined as oxygen < 60 mm Hg
Hypercarbia is defined as CO2 > _ mm Hg
Hypercarbia is defined as CO2 > 45 mm Hg
5 causes of hypoxemia
- Low FiO2
- Hypoventilation
- Diffusion deficit
- Shunting
- Dead space
Atelectasis is an example of (shunt/dead space)
Atelectasis is an example of shunt
Edema is an example of (shunt/dead space)
Edema is an example of shunt
Pulmonary bullae is an example of (shunt/dead space)
Pulmonary bullae is an example of dead space
Pulmonary embolism is an example of (shunt/dead space)
Pulmonary embolism is an example of dead space
_ is a cause of hypoxemia that does not respond well to supplemental oxygen
Shunting is a cause of hypoxemia that does not respond well to supplemental oxygen
Pneumonia is an example of (shunt/dead space)
Pneumonia is an example of shunting
Individuals with diffusion deficits tend to decompensate very quickly with exertion due to _
Individuals with diffusion deficits tend to decompensate very quickly with exertion due to slow diffusion
Our normal response to hypercapnia is to _ ; however, this sometimes fails due to _
Our normal response to hypercapnia is to increase minute ventilation ; however, this sometimes fails due to blunted response to PaCO2 overtime, respiratory muscle fatigue, shallow breaths
TV
IRV, ERV
RV
Inspiratory capacity
Functional residual capacity (FRC)
Vital capacity
TLC
Draw volume-time spirometry curve
Draw flow-volume loop
In order to determine the functional residual capacity of the lungs we can use _ or _ tests
In order to determine the functional residual capacity of the lungs we can use Gas dilution tests or body plethysmography
The diffusing capacity of the lungs is measured using _ gas due to its _ affinity for Hb
The diffusing capacity of the lungs is measured using carbon monoxide gas due to its high affinity for Hb
DLCO will be _ in anemia
DLCO will be artificially low in anemia; this is low hemoglobin
DLCO will be _ in pulmonary hemorrhage
DLCO will be artifically high in pulmonary hemorrhage; there is too much hemoglobin
Intrinsic restrictive lung diseases are those that impair the _
Intrinsic restrictive lung diseases are those that impair the lung parenchyma
Extrinsic restrictive lung diseases are those that impair the _
Extrinsic restrictive lung diseases are those that impair the chest wall/ abdomen or neuromuscular system
Abnormalities of the chest wall that might cause restrictive lung disease include _
Abnormalities of the chest wall that might cause restrictive lung disease include fibrothorax, kyphoscoliosis, morbid obesity
Myasthenia gravis and polio might cause restrictive lung disease via _
Myasthenia gravis and polio might cause restrictive lung disease via weakness of the respiratory muscles
Obstructive lung diseases can have air-trapping that causes vital capacity to (increase/ decrease)
Obstructive lung diseases can have air-trapping that causes vital capacity to decrease
* Since residual volume increases, VC decreases
