Session 9_Pulmonary Ventilation and Circulation Flashcards
What is the highest recorded “sneeze speed”?
99 miles per hour
What is the surface area of the lungs roughly the same size as?
a tennis court
How much water do we lose everyday through breathing?
1/2 liter
How many lobes does the right lung have?
3
How many lobes does the left lung have?
2
The lungs occupy all thoracic cavity except:
mediastinum
3rd cervical vertebra, to 6th =
location (posteriorly) larynx
Larynx separates:
separation of food of air
The right lung has 2 fissures =
horizontal and oblique fissures
The left lung has 1 fissure =
oblique fissure
The left lobe also has the little extension of:
lingula
What is the potential pathology of the pleurisy/ pleuritis?
inflammation of pleural cavity –> rough –> friction rub
What are some potential causes of pleurisy?
chest trauma, cancer, pulmonary embolis, autoimmune disease (lupis), rheumatoid arthritis.
What part of the O2 transport system would be involved in pleurisy?
????
inspiration
What type of connective tissue is the lung tissue?
primarily elastic
What does the elasticity of healthy lungs help reduce?
Reduce the work of breathing
The bronchopulmonary segments of the lungs are separated by:
connective tissue septa
The bronchopulmonary segments of the lungs are served by own:
lung and artery
The bronchopulmonary segments received air from:
individual bronchus
Cancer caught early in bronchopulmonary segments, can be removed without:
affecting other parts –> people can survive
What are three regions of the Right Upper bronchopulmonary segments?
- apical
- anterior
- posterior
What are the 2 regions of the Right middle bronchopulmonary segments?
- lateral
2. medial
What are the 5 regions of the Right lower (base) bronchopulmonary segments?
- anterior
- superior
- lateral
- posterior
- medial
What are the 4 regions of the Left Upper bronchopulmonary segments
- apical posterior
- anterior
- superior (lingula)
- inferior (lingula)
What are the 4 regions of the Left Lower(base) bronchopulmonary segments?
- anterior
- superior
- lateral
- posterior
How many auscultation spots are there?
9
How would you located the Right lung using surface landmarks?
- 1” above rib 1
- crosses costal cartilage 6
- midclavicular at rib 6
- midaxillary at rib 8
- vertebral border at rib 10
- inferior border 2 rib widths above diagphram
How would you located the Left lung using surface landmarks?
- 1” above rib 1
- deep to manubroclavicular joint
- midsternally to rib 4
- jogs to left, continues to rib 6
- midaxillary rib 8
- vertebral border at rib 10
The upper respiratory tract is from:
nasal and oral orifices to the false vocal cords in the larynx
The upper respiratory tract includes what 4 structures?
- nose
- nasal cavity
- pharynx (naso-, oro-, layrngo-)
- Larynx
The lower respiratory tract includes what 7 structures?
- trachea
- R & L primary bronchi (bronchus -singular)
- secondary, tertiary, etc. bronchi
- bronchioles
- terminal bronchioles
- respiratory bronchioles
- alveolar ducts –> alveolar sacs –> alveoli
The lower respiratory tract is from level of:
true vocal cords to the alveoli
The lower respiratory tract is divided into what 2 regions?
- conducting
2. respiratory zones
What side does aspiration usually happen on?
R side, R> vertical
What is the conducting zone?
trachea through terminal bronchioles
Where does the trachea bifurcate?
~ T7
The trachea bifurcates into:
R and L main bronchi
The R and L main bronchi further divide into:
lobar bronchi: 3 on right, 2 on left
The lobar bronchi further divide into:
segmental bronchi (tertiary)
What helps move mucous out?
cilia
About how many orders of branching air passageways are there?
~23
The bronchioles (air passages) of the conducting zone, are ____________________ in diameter?
The terminal bronchioles of the conducting zone, are ____________________ in diameter?
Conducting zone + upper airway =
ANATOMIC DEAD SPACE
Space in respiratory passage where gas exchange does not occur = ~
~150mls
Where is most of the are?
in respiratory bronchioles and alveoli
The transition and respiratory zone begins where terminal bronchioles feed into:
respiratory bronchioles
Terminal bronchiole –>
respiratory bronchioles –> alveolar duct–> alveoli (multiple = alveolar sac)
The respiratory zone contains about how many liters of air at rest?
~2.5L
The respiratory zone contains about how many liters of air with max. inspiration?
4.6L
The respiratory zone comprises the majority of:
the 4-6L lung capacity
What are the walls of the alveoli composed of?
single layer of Type I cells; squamous epithelial
surrounded by basement membrane
The external surface of the alveoli are covered by:
a ‘web’ of capillaries
How much air vs blood =
0.8 (4L O2: 5L blood)
Albeolar + capillary walls+ fused basement membrane =
respiratory membrane
~250ml O2 leave alveoli to blood, 200ml CO2 diffuse from blood to gas in:
alveoli per minute
What type of cells in the alveoli secrete surfactant?
Type II cells
The alveoli also have ___________ and _______________.
pores and macrophages
Provide one example of a pathology that affects efficiency of the alveoli?
pulmonary edema (auscultation - may hear crackles)
Respiratory membrane =
alveoli, capillaries and basement membrane
- also for respiration
What part of O2 transport system involved with a pathology affecting alveoli?
???
Dead space =
can’t do gas exchange
Anatomical deal space =
volume of all the space of the respiratory system other than alveoli and their closely related gas exchange areas
Physiological dead space =
alveolar dead space + anatomical dead space
In a healthy individual anatomical and physiological dead spaces will be:
similar
Blood supply to the lung tissue:
bronchial arteries & pulmonary veins
Bronchial arteries come of aorta and go into the lungs through the:
hilum
1-2% of cardiac output
** to supply lung tissue
Where do pulmonary veins carry blood?
carrying oxygenated blood –> artrium
The parasympathetic NS =
constrict air tubes
Sympathetic NS =
dilate air tubes (motor fibers)
During parasympathetic activation ACh is release –>
smooth muscle contraction
Parasympathetic NS innervation increases:
airway resistance
Parasympathetic NS innervation slows and reduces:
volume of airflow
Sympathetic NS innervation is:
weak direct control by sympathetic nerve fibers
Sympathetic NS activation by EPI and NE –>
smooth muscle relaxation
The stronger effect by EPI and NE released in blood:
released by adrenal medulla following SNS stimulation
Sympathetic NS innervation reduces:
airway resistance and enhances flow
Name the 5 major functional events of respiration:
- pulmonary ventilation
- external respiration
- Transport of respiratory gasses
- Internal respiration
- Regulation of respiration / ventilation
pulmonary ventilation
mass movement of air
external respiration =
lung level (move O2 from alveoli –> capillaries
respiration = _____________ process
cellular
Internal respiration =
@ tissue level (blood –> tissue)
Pulmonary ventilation is defined as
movement of air into and out of lungs - commonly called “breathing”
Mechanisms of expansion / contraction of lungs =
- contraction of diaphragm: lengthens or shortens the chest cavity
- elevation / depression of ribs
What is the role of the diaphragm in pulmonary ventilation?
- quiet inspiration
- contracts: dome shape “flattens”
- increases thoracic volume
During expiration, the diaphragm:
relaxes back to dome shape
and decreases thoracic volume
External intercostals (additional inspiration muscles) function in pulmonary ventilation to:
elevate ribs
Other muscles that assist in pulmonary ventilation are:
SCM, scalenes, anterior serrati, pectoralis minor and erector spinae muscles
One clinical intervention =
inspiratory muscle training (IMT)
Expiration muscles involved in pulmonary ventilation are:
- internal intercostals
2. rectus abdominis
The expiration muscles in pulmonary ventilation are recruited with increased:
respiratory demands/ forced expiration
Respiratory pressures are always described relative to:
atmospheric pressure (Patm)
Atmospheric pressure =
760 mmHg @ sea level
Intrapulmonary pressure (Ppul or Palv) =
alveolar pressure
Intrapulmonary pressure wants to equalize with what?
atmospheric pressure
Intrapleural pressure (Pip) =
pressure in the pleural cavity
About how many mmHg is intrapleural pressure?
~.4 mmHg (lower than Patm by ~4mmHg)
As the pressures change in the alveoli w/ stimulation of breathing, will see air pulled in or pushed out?
???
Boyle’s Law: @ constant temperature, the pressure of a gas varies _______________ with its volume
@ constant temperature, the pressure of a gas varies INVERSELY with its volume
P1V1 =
P2V2
Alveolar pressure (Palv) =
pressure inside lung alveoli
During inspiration: Palv drops slightly to:
~-1 cm H2O
During inspiraiton the Palv pressure drop is enough change to allow 500 ml air to be pulled into lungs in about how many second?
~ 2 seconds
During expiration, Palv rises to:
~ 1 cmH2O
driving air out of alveoli in ~2-3 seconds
Transpulmonary pressure (Palv - Pip) =
keeps air spaces of lungs open
Transpulmonary pressure is the difference between the alveolar pressure and the:
pleural pressure
Lung collapse (or partial) =
atelectasis
Presence of air in intrapleural space =
pneumothorax
The measure of the change in lung volume that occurs with a given change in transpulmonary pressure =
lung compliance
Lung compliance is determined by:
distensibility (elastic forces) of lung tissue and
alveolare surface tension (surfactant)
Interstitial lung disease =
severe, quick/ acute, decreased distensibility
What does surfactant help reduce?
helps reduce surface area to avoid collapsing
What is the surface tension principle?
- “raindrop”
- alveoli w/o surfactant
- smaller the alveolus, greater the alveolar pressure caused by the surface tension
what is surfactant made up of?
phospholipids, proteins, and ions
What is the function of surfactant?
greatly reduce surface tension (prevent collapsing)
surfactant reduces the effort required by respiratory muscles to expand the:
lungs
Less surfactant =
less distensible
What 2 forces act to pull the lungs from the thorax wall (parietal pleura)?
*which would cause lung collapse
- lungs natural tendency to recoil
2. surface tension of alveolar fluid
Is intrapleural pressure negative or positive?
negative
Why is the intrapleural pressure negative?
- it is opposed by natural elasticity of chest wall
- it maintains pleural fluid adhesive force
- combination of all forces
During inspiration, the diaphragm ______________. The ____________________ dimension of thoracic cavity increase.
contracts
superior-inferior
During inspiration the external intercostal muscles lift the rib cage and pull the sternum _________________ and there is _________________ expansion of the thoracic cage
sternum superiorly-lateral
anterior-posterior expansion of thoracic cage
During inspiration, the thoracic ________________ increases by ~__________ .
VOLUME increases by ~500ml
An increase in volume during inspiration leads to _________________ in pressure.
decrease
During (quiet) expiration, the diaphragm ___________________, the rib cage ___________________ and the lungs ___________________
diaphragm relaxes
rib cage resumes resting position
lungs recoil
During expiration, thoracic and intrapulmonary volumes ______________ –> compressing the alveoli.
decrease
During expiration Palv ___________.
rises
If Palv > Patm?
gases flow out of the lungs
What are the 3 components working during quiet breathing?
- compliance work or elastic work
- tissue resistance work
- airway resistance work
During pulmonary ventilation, how much energy expenditure is required?
3-5% total body energy expenditure required for pulmonary ventilation
When does forced inspiration/ expiration occur?
occurs when need an increase in gas exchange
** accessory muscles are recruited
see photo on slide 51
see photo on slide 51
For airway resistance, the non-elastic source is:
friction
What is the equation for airway resistance?
F = ∆ P / R
lung capacity =
2 or more volumes added together
see slide 53
see slide 53
tidal volume (TV) =
amount of air inhaled or exhaled w/ each breath under resting conditions
inspirations reserve volume (IRV)
amount of air that can be forcefully inhaled after a normal tidal volume inhalation
expiration reserve volume (ERV)
amount of air that can be forcefully exhaled after a normal tidal volume exhalation
Residual volume (RV)
amount of air remaining in the lungs after a force exhalation
Total lung capacity (TLC)
maximum amount of air contained in lungs after a maximum inspiration effort
vital capacity (VC)
maximum amount of air that can be expired after a maximum inspiratory effort
Inspirations capacity (IC)
maximum amount of air that can be inspired after a normal expiration
functional residual capacity (FRC)
volume of air remaining in the lungs after a normal tidal volume expiration
TLC =
TV + IRV + ERV + RV
VC =
TV + IRV + ERV (should be 80% TLC)
IC =
TV + IRV
FRC =
ERV + RV
V1(1) ==
.
VE (1)=
.
Minute respiratory volume=
RRXV(t)
FVC =
.
FEV (1)=
.
Surfactant is not secreted into alveoli until:
~7 months gestation
What are the pulmonary complications if a baby is born prematurely @ ~ 7 months gestation?
List 2 physiological explanations for the complications:
infant will require greater effort by respiratory muscles to expand lungs
- more surface tension, more pressure to collapse
- less distensible b/c lacks surfactant
distensibility =
a determinant of stress on the vessel wall. A decreased distensibility might increase the risk of arterial wall damage.
Alveolar ventilation (Va) =
total volume of new air entering the alveoli and their adjacent gas exchange areas each minute
Va =
Freq X (Vt - Vd)
Alveolar ventilation (per minute) is a major factor in determining the concentration of:
O2 and CO2 in the alveoli
Describe normal respiratory conditions:
larger bronchioles and bronchi near trachea provide the greatest amount of airflow.
Normal respiratory conditions: Why do the bronchioles and bronchi near the trachea provide the greatest amount of resistance to airflow?
???
In disease conditions: Why do smaller bronchioles provide greater resistance to airflow?
???????
more constricted???
What are 4 characteristics of pulmonary arteries?
- thin walled
- short
- larger diameters than systemic counterparts
- much more compliant: can accommodate stroke volume output of R ventricle
The lungs have about ~450Mml of blood.. How much is in the pulmonary capillaries?
70ml
Blood from lungs gets distributed to:
alveoli (with best oxygenation)
Low (O2) in alveoli causes capillary constriction which is _____________________ to systemic capillary reaction to low (O2).
opposite
Why is the response of the alveoli to low O2 (capillary constriction) opposite to the systemic capillary reaction to low O2?
???????
If Palv > Ppc –>
capillaries close and no blood flow
With EX blood volume increases up to:
4-7 fold
Additionally, with EX, blood volume:
- increases the # of open capillaries
- distends(swell) capillaries and therefore increases rate of flow
- increases pulmonary pressure - minimally
