Respiratory System: Pulmonary Ventilation and Circulation Flashcards
How many lobes of the right lung?
3 lobes
How many lobes of the left lung?
2 lobes
What type of pleura lies against the lung?
visceral pleura
What type of pleura lies against the chest wall?
parietal pleura
What lies to between the lungs and the chest wall?
pleural cavity (w/ small amount of fluid – allows lungs to move)
Tissue type of the lungs?
elastic connective tissue (elastic recoil on expiration)
Bronchopulmonary segments are separated by what?
connective tissue septa
Bronchopulmonary segments receive air from what?
individual bronchus
Each bronchopulmonary segment has what 2 things?
each segment has an artery and vein going into the segment
Bronchopulmonary segments of the upper lobe of the right lung (3)
- apical
- anterior
- posterior
Bronchopulmonary segments of the middle lobe of the right lung (2)
- lateral
- medial
Bronchopulmonary segments of the lower (base) lobe of the right lung (5)
- anterior
- superior
- lateral
- posterior
- medial
Bronchopulmonary segments of the upper lobe of the left lung (4)
- apical posterior
- anterior
- superior (lingula)
- inferior (lingula)
Bronchopulmonary segments of the lower (base) lobe of the left lung (4)
- anterior
- superior
- lateral
- posterior
Beginning and end of the upper respiratory tract?
nasal & oral orifices to the false vocal cords in the larynx
Structures of the upper respiratory tract? (4)
nose –> nasal cavity –> pharynx –> larynx
Beginning and end of the lower respiratory tract?
true vocal cords to alveoli
Pathway of lower respiratory tract?
trachea –> R & L primary bronchi –> secondary/tertiary bronchi –> bronchioles –> terminal bronchioles –> respiratory bronchioles –> alveolar duct –> alveolar sacs –> alveoli
2 regions of lower respiratory tract?
- conducting zone
- respiratory zone
Function of the conducting zone?
getting air down to respiratory zone
Beginning and end of the conducting zone?
trachea thru terminal bronchioles
Trachea bifurcates @ what level of the spinal cord?
T7
Trachea bifurcates into what?
R and L main bronchi
R and left main bronchi divide into what?
Lobar bronchi: 3 on right and 2 on left
Lobar bronchi divide into what?
segmental bronchi (tertiary)
How many orders of branching air passages?
23
What is included in anatomic dead space?
conducting zone + upper airway
What is the space in the respiratory passage where gas exchange does NOT occur?
anatomic dead space
Function of respiratory zone?
gas exchange
Beginning and end of respiratory zone?
begins where terminal bronchioles feed into respiratory bronchioles
How much air does the respiratory zone contain at rest?
2.5 L
How much air does the respiratory zone contain during max inspiration?
4-6 L
What type of tissue cells composes the walls of the alveoli?
single layer of Type I cells (squamous epithelium)
The external surface of the alveoli is covered by what?
web of capillaries
What comprises the respiratory membrane?
alveoli + capillary walls + fused basement membrane
How much O2 leaves the alveoli to go to the blood per minute?
250 ml
How much CO2 diffuses from the blood into the alveoli per minute?
200 ml
What type of cells secrete surfactant?
Type II cells
Amount of anatomical dead space?
150 ml
Amount of physiological dead space?
150 ml when healthy
When the alveoli close down, they become what kind of dead space?
physiological dead space (up to 1500 ml)
Blood supply pathway?
aorta –> bronchiole arteries –> lung tissue –> deoxygenated blood mixes with oxygenated blood in the pulmonary veins
How do the alveoli receive blood?
get blood nutrients thru capillaries
1-2% of cardiac output goes to what?
goes to the bronchial arteries to supply the blood tissue and then flows back through the pulmonary vein to the left atrium
What carries deoxygenated blood from the blood tissue and oxygenated blood from the heart?
pulmonary veins
Low O2 in alveoli causes what?
capillary constriction
What does it mean if Palv > Ppc?
capillaries closed, no blood flow
Effects of exercise on blood distribution? (2)
- blood volume increases 4-7 fold
- distend capillaries = increase rate of flow
Parasympathetic innervation does what to the airway?
constricts air tubes
Ach release from parasympathetic innervation does what?
smooth muscle contraction (increases airway resistance - slow and reduces volume of airflow)
Ach inhibitors function?
vasodilation
Sympathetic innervation does what to the airway?
dilates air tubes
Epi/Norepi release from adrenal medulla following sympathetic innervation does what?
smooth muscle relaxation (reduces airway resistance, enhances flow)
Five major functional events of respiration?
- pulmonary ventilation
- external respiration
- transport of respiratory gases
- internal respiration
- regulation of respiration/ventilation
What event of respiration involves movement of air into and out of the lungs?
pulmonary ventilation
Quiet inspiration
contraction of the diaphragm lengthens chest cavity (increases thoracic volume)
Quiet expiration
diaphragm relaxes back to dome shape (decrease thoracic volume)
Additional inspiration muscles (6)
- external intercostals (elevate the ribs)
- SCM
- scalenes
- serratus anterior
- pectoralis minor
- erector spinae
Additional expiration muscles (2)
- internal intercostals
- rectus abdominus
What is the atmospheric pressure at sea level?
760 mmHg
Boyle’s Law
pressure and volume are inversely related (P1V1 = P2V2)
Intrapulmonary pressure (Ppul or Palv)
alveolar pressure
- wants to equalize with atmospheric pressure
- inspiration: drops about 1 cm H2O
- expiration: rises about 1 cm H2O
Palv > Patm
gases flow out of the lungs
Intrapleural pressure (Pip)
pressure in pleural cavity
– 4 mmHg lower than atmospheric
Transpulmonary pressure
Palv - Pip (difference between alveolar pressure and intrapleural pressure)
– keeps air spaces open
Atalectasis
hole in lung –> lose negative pressure
Pneumothorax
build up of pressure in pleural space –> collapsed lung
What is known as the measure of the change in lung volume that occurs with a given change in transpulmonary pressure?
lung compliance (distensibility)
Function of surfactant?
reduces surface tension of alveoli
The _____ the alveolus, the _____ the alveolar pressure caused by surface tension.
smaller, greater
Equation for flow
Flow = (change in pressure) / (resistance)
Region requires how much energy expenditure?
3-5% total body energy expenditure
What makes up Inspiratory capacity?
Inspiratory reserve volume and tidal volume
What makes up functional residual capacity?
expiratory reserve volume and residual volume
What makes up vital capacity?
- Inspiratory reserve volume
- tidal volume
- expiratory reserve volume
Total lung capacity
- inspiratory reserve volume
- tidal volume
- expiratory reserve volume
- residual volume
Tidal volume (TV) definition
amount of air inhaled or exhaled with each breath under resting conditions
Inspiratory reserve volume (IRV) definition
amount of air that can be forcefully inhaled after a normal tidal volume inhalation
Expiratory reserve volume (ERV) definition
amount of air that can be forcefully exhaled after a normal tidal volume exhalation
Residual volume (RV) definition
amount of air remaining in the lungs after a forced exhalation
Total lung capacity (TLC) definition
maximum amount of air contained in lungs after a maximum inspiratory effort
Vital capacity (VC) definition
maximum amount of air that can be expired after a maximum inspiratory effort
Inspiratory capacity (IC) definition
maximum amount of air that can be inspired after a normal expiration
Functional residual capacity (FRC) definition
volume of air remaining in the lungs after a normal tidal volume expiration
Alveolar ventilation per minute definition and equation
total volume of new air entering the alveoli and their adjacent gas exchange areas each minute
– Va = Freq x (Vt - Vd)
Minute Respiratory Volume equation
RR x Vt
