Respiratory A&P Flashcards
what is included in respiration?
- ventilation
- gas exchange between blood and alveoli
- gas delivery to the tissues
- gas exchange between blood and tissues
- oxygen utilization by tissues
- return of gases from tissues to lungs
- exhalation
distinguish between internal and external respiration
- Internal → oxygen utilization and gas exchange in tissues
- External → ventilation and gas exchange in lungs
describe the movement of the diaphragm with breathing
flattens with inhalation
domes with exhalating
what may limit diaphragm displacement?
- obesity
- pregnancy
- size of GI organs
- ascites
how does the supine position impact the diaphragm?
there are no effects of gravity so the level of the diaphragm rises and there is greater excursion
lung volumes are lower b/c of elevated position of the abdominal organs
how does the upright position impact the diaphragm?
it is pulled down due to gravity and there is reduced excursion but lung volumes are increased
how does the sidelying position impact the diaphragm?
- the hemidiaphragms are unequal in their positions here
- uppermost side drops to a lower position and has less excursion than in sitting
- lowermost side (dependent) rises higher in the thorax and has greater excursion than in sitting position
why would a pneumonia pt want to be positioned sidelying with their “bad” lung higher?
this will allow the “good” lung on the lower side to have greater excursion
how does the external intercostal impact respiration?
- it is a muscle of inspiration
- contraction of this muscle pulls the lower rib up and out toward the upper rib
- this elevates the ribs and expands the chest
how does the internal intercoastal impact respiration?
- it is a muscle of expiration
- contraction of this muscle pulls the ribs downward
briefly describe inspiration
- an active process at rest and during exercise
- involves contraction of diaphragm and external intercostals
- accessory respiratory muscles are involved in pulmonary pathologies
briefly describe expriation
- at rest, is a passive process and achieved through the elastic recoil of the lung
- relaxed breathing → ribs drop, diaphragm relaxes and domes
- elastic recoil → rebound of the lungs after having been stretched by inhalation
describe forced expiration
- involves the abdominals and internal intercostal muscles
- contraction of the intercostals pull the ribs downward reducing the volume of the thoracic cavity and compressing the lungs
- contraction of the abdominal muscles force the viscera upwards against the diaphragm also compressing the abdominal cavity and hence the thoracic cavity
list the muscles of inspiration
- external intercostals
- SCM
- Scalenes
- Upper Trapezius
- Pec Major and Minor
- Serratus Anterior and Rhomboids
- Latissimus dorsi
- Serratus posterior superior
- thoracic erector spinae muscles
where is the apex of the lungs?
in the root of the neck
highest point being approximately 1 inch above the middle third of each clavicle
describe the lobes, fissures, and segments of the R Lung
- 3 lobes
- RUL → has 3 segments
- RML → has 2 segments
- RLL → has 4 segments
- 2 fissures
- oblique (major) fissure → separates the RLL from the RML and RUL
- horizontal (minor) fissure → separates the RML from the RUL
Describe the lobes, fissures, and segments of the L Lung
- 2 Lobes separated by an oblique fissure
- LUL → has 4 segments
- anterior
- apico-posterior
- superior linguar
- inferior linguar
- LLL → has 4 segments
- apical
- anterior
- posterior
- lateral
- LUL → has 4 segments
what makes up the respiratory zone within the lungs?
- respiratory bronchioles
- alveolar ducts
- alveoli
T/F: Inspiration is always a passive process
FALSE
active process
an increase in the volume of the thoracic cavity and the lungs leads to a __________ in intrapulmonary pressure
reduction
(reduces pressure in the lung/alveoli)
what is minute ventilation?
- the total volume of air that is inhaled or exhaled in one minute
- Assessment of effective ventilation
- expressed in L/min and is calculated by multiplying the ventilatory rate and tidal volume
what is a primary determinant of lung compliance?
- Elasticity → ability to return to initial size after being stretched
what disease impacts lung elasticity?
- emphysema degrades elastin which results in an increased compliance and a very easily inflated lung that now has a reduced capacity to recoil
- edema → decreased compliance
what does low/high compliance indicate?
- low → indicates a stiffer lung (can be thought of as a thicker balloon)
- high → indicates a more pliable lung (a thinner balloon)
how is compliance lowered in the lungs?
reduced or lowered by factors that produce a resistance to distension such as infiltration of connective tissue into the lung parenchyma (pulmonary fibrosis)
how does surface tension impact lung compliance?
helps favor the recoil of the lungs inward and therefore helps determine compliance
what is surfactant?
a compound that reduces surface tension
(w/o it recoil goes up and compliance goes down)
what is the role of surface tension in the lungs?
- it is created by fluid secreted onto the lining of the alveoli
- resists lung expansion/distension
- acts to collapse the alveolus and raise the pressure of the alveolar air
T/F: pulmonary ventilation and perfusion are equally distributed
FALSE
pulmonary ventilation → 2.5x greater at the base than at the apex
pulmonary perfusion → 6x greater at base than apex (due to gravity)
what is the purpose of a ventilation perfusion scan
- a test that measures air and blood flow in lungs
- most often is used to help diagnose or rule out a pulmonary embolism
- involves radioactive albumin injected into the blood (perfusion) and addition of a radionuclide such xenon and technetium into the air breathed in
what is Dalton’s Law?
the total pressure of a gas mixture is equal to the sum of the pressure of each in it
how does increased CO2 within the blood impact pH?
reduces pH and makes blood more acidic
results in hypoventilation and reduced exhalation volumes
how does decreased CO2 within in the blood impact pH and respiration?
increased blood pH → more alkalotic
hyperventilation, reduced exhalation volumes
