A & P of Respiratory System Flashcards
What is most basic component of voice and speech production?
breath stream
What is respiratory system composed of?
oral/nasal cavities
pharynx
larynx
trachea
lungs: bronchi
bronchioles
alveolar sacs2 broad categories of muscles of respiration
muscles of inspiration
muscles of expiration
types of inspiration
- quiet inspiration (vegetative breathing): use diaphragm only
- forced inspiration: use intercostals and more
types of thorax expansion on inspiration
- vertical expansion: primarily thru diagphram
2. transverse expansion
diaphragm
- primary muscle for inspiration
- large, inverted bowl
- attaches along lower margins of rib cage, sternum and vertebral column
- completely separates abdominal and thoracic cavities
- Central Tendon: when muscle contracts, pulls tendon down and forward
- muscle fibers radiate from it to attach to sternum, ribs and vertebrae
- xiphoid process is anterior most attachment
- attaches to ribs 7-12 and costal cartilages
- attaches to L1-4
accessory muscles of inspiration
assist the diaphragm by elevating rib cage
- external intercostals
- neck: sternocleidomastoid & scalenes
external intercostals
- perform some functions that are purely speech-related
- 11 residing between the 12 ribs
- originate on lower surface of rib and move down and inward to attach to upper surface of rib immediately below
- translucent intercostal membrane separates them from internal intercostals
- elevate rib cage, causing twisting of cartilaginous portion of ribs (active inspiration)
- when force is relaxed, they return to original shape (passive expiration)
accessory muscles of neck
responsible for flexion and extension that can assist in forced inspiration
- sternocleidomastoid
- scalenes (anterior, middle, posterior)
Sternocleidomastoid
- origin on mastoid process of temporal bone, runs down neck and inserts at sternum and clavicle
- paired – right and left
- seen when head turned to side
- when contracted separately, head will rotate to that side
- when contracted together, lift sternum and anterior rib cage
scalenes
- provide head stability and facilitate rotation
- assist in elevation of rib cage for inspiration
- important for speech b/c provide neck stability and control
- origin is cervical vertebrae and insertion is surface of first two ribs
muscles of forced expiration
-requires muscles acting indirectly on lungs to squeeze out air
-achieved by pulling down on rib cage or forcing diaphragm up
-normal expiration is merely passive response to relaxation of diaphragm
2 groups:
1. muscles of thorax, back and upper limb
2. abdominal muscles of expiration
anterior thoracic muscles
- internal intercostals (interosseous portion)
- transversus thoracis
- innermost intercostals
internal intercostals (interosseous portion)
- significant contributors to forced expiration
- originate on superior margin of each rib and run up and medially to insert into inferior surface of rib above
- provide support and spacing of ribs along with external intercostals
- function to pull rib cage down to decrease lung volume
innermost intercostals
- deepest of intercostals
- fibers run between inner surface of ribs
- same origin and insertion as internal intercostals
- attach with subcostal muscles
- innervation via intercostal nerves
transversus thoracis
found on inner surface of rib cage
contraction would depress rib cage
abdominal aponeurosis
tendenous structure running from xiphoid process to pubic symphysis
wraps around anterior portion of abdomen
linea alba runs in middle - muscles attach to it
anterolateral abdominal muscles
help expiration by compression of abdominal viscera
- transversus abdominus: reduce volume of abs
- internal oblique abdominus: rotate & flex
- external oblique abdominus: rotate & flex
- rectus abdominus: sit-up muscle
posterior abdominal muscles
- quadratus lumborum: bilateral contraction helps fixate abdominal wall to support expiration
muscles of upper limb
latissimus dorsi: assists in stabilization of abdominal wall for expiration
respiration
exchange of gas between and organism and its environment
air pressure
force exerted on walls of a chamber by molecules of air
Pleural Linkage
allow thorax and lungs to act as integrated unit - vital to inhalation and exhalation
Visceral pleura covers lungs.
Parietal pleura lines thorax.
Pleural space in between contains pleural fluid, which has negative pressure. This pressure holds the pleurae in close proximity.
Boyle’s Law
As volume of chamber increases, pressure decreases (assuming gas of constant temp).
Inhalation: muscles cause chamber to expand and pressure to be negative, so air flows in.
Exhalation: muscles cause chamber to contract and pressure to be positive, so air flows out.
negative pressure
decrease in air pressure that causes air to enter the chamber to equalize pressures
positive pressure
increase in air pressure that causes air to leave the chamber to equalize pressures
measurement of respiration
flow
volume
lung capacities
pressure
respiratory cycle
one inspiration and one expiration normal for adults: 12-18 cycles per minute newborns: 40-70 cycles/min children: 20-25 cycles/min (quiet breathing)
quiet tidal respiration
amount of airflow in and out of lungs in one cycle of quiet breathing
volume
estimate of amount of air a compartment can hold
capacity
combination of volumes that express physiological limits
types of volumes
Tidal Volume Inspiratory Reserve Volume Expiratory Reserve Volume Residual Volume Dead Air
Dead Air
volume of air left in upper airway that cannot undergo gas exchange because there are no alveoli in these areas
adult average = 150 cc
Tidal Volume (TV)
volume of air we breathe during respiratory cycle
not static; varies with exertion, age, size
increases with exertion
Inspiratory Reserve Volume (IRV)
volume that can be inhaled after tidal inspiration
amount of air in reserve beyond tidal inhale
Expiratory Reserve Volume (ERV)
amount of air that can be breathed out following passive tidal expiration
measured from end of expiration
Residual Volume (RV)
volume remaining in lungs after maximum expiration
cannot be exhaled no matter how you try
*keeps lungs from collapsing
Capacities
-volumes combined to characterize physiologic needs
Vital Capacity
Functional Residual Capacity
Total Lung Capacity
Inspiratory Capacity
Vital Capacity
capacity available for speech
total volume of air that can be exhaled after a maximal inhalation
VC=IRV + ERV + TV
Functional Residual Capacity (FRC)
volume of air remaining in body after passive exhalation
FRC = ERV + RV
Inspiratory Capacity (IC)
maximum inspiratory volume possible after tidal expiration
IC = TV + IRV
Total Lung Capacity (TLC)
volume of air involved in maximal respiratory cycle plus residual volume
TLC = TV + IRV + ERV + RV
checking action
process of restraining airflow for speech
if problem, person limited to short bursts of speech
If we get down to resting lung volume and need to continue speaking, we use muscles of expiration to push beyond the resting volume.
forces of passive exhalation
- gravity: pulls down viscera and ribs
- elasticity: spongy lung tissue returns to natural shape
- torque: inhalation twists ribs, so ribs want to untwist
Life vs. Speech Breathing
See table 1.3 on p. 14
nervous system control of respiration
-medulla in brainstem
-O2 and CO2 receptors
-In smooth muscles of tracheobronchi:
pulmonary stretch receptors (PSR)
rapidly adapting receptors (RARs)
-Breathing for speech adds:
primary motor and sensory cortex, cerebellum, thalamus and limbic system
