316 Respiratory/ 1st part of phonation

Test 2 definitions/#'s to remember

**Breathing**

inhalation (inspiration) & exhalation (mechanics)

**Respiration**

gas exchange at level of cell (in the alveoli) 

**Expiration**

oxygen carbon dioxide being exchanged at molecular level

**Ventilation**

moving are into and out of the lower airways (how much air is moving into and out of system)

**Diffusion**

movement of molecules of fluid from high concentration to low concentration

**Boyle’s Law**

If the volume of a gas is increased, given a constant temperature, the pressure will decrease (and vice versa)

Fluids (air) flow from **greater** pressure to **--------** pressure

**lesser**

Rib cage has

12 sets of ribs

lungs are made up of % air

90%

**Tone**

low level of activity: “readiness” to work

Tension > load

shorten/concentric

Tension < load

lengthen/eccentric

tension = load

isometric

Muscles can shorten by

50%

Muscles function within

10%

**Agonist**

muscle that contracts to achieve a given movement

**Antagonist**

**:** muscle that opposes contraction of another muscle

* Stretched by action of agonist

increasing force ----- velocity

decreases

motor equivalence

Use different motor plans to achieve the same target.

quiet tidal breathing

breathing at rest

visceral

lung

parietal

thoracic

tidal breathing average

12-15 breaths/min

REL/EEL

resting expiratory level, ending expiratory level

35-40%

**Relaxation pressure is positive when it acts to ------ lung volume**

decrease

**Relaxation pressure is negative when it acts to ------ lung volume.**

increase

Thorax

* = compressed spring & its elastic recoil exerts an expansion force.

Lungs

stretched spring, with elastic recoil exerting a compression force.

Relaxation curve

relaxation pressure as a function of lung volume displayed graphically.

**Transthoracic pressure: Alveolar—atmospheric pressures**

**Amount of pressure needed to expand or contract the lungs & chest wall simultaneously**

**Negative transthoracic pressure**

**alveolar pressure is lower than atmospheric (& vice versa)**

Curve below RLV

relaxation pressures working to **increase** lung volume

Curve above RLV

relaxation pressures working to **decrease** lung volume

checking action

inhibiting relaxation pressure \n using the inspiratory muscles

Pressures above ----- vital capacity are too great to sustain phonation.

60%

Tidal Breathing Inspiratory—Expiratory Phases

40%–60%

Speech Breathing Inspiratory—Expiratory Phases

10%–90%

“Adaptive Control”

Changeable internal & external demands require speech breathing system to be highly adaptable

Clavicular Breathing (paradoxical)

Over-activation of sternocleidomastoid and other shoulder muscles with lesser activation of diaphragm. Lateral expansion of thorax is limited, with emphasis on vertical expansion.

Chest (pear shape up, up & in, high breathing)

Activation of abdominal muscles limits downward excursion of diaphragm, but

* Antero-posterior expansion of chest wall exerts lateral pull on diaphragm, allowing vertical expansion of lungs.

Diaphragmatic (pear shape down, down & out, low breathing)

Antagonist muscle contraction of \n abdomen and thorax are minimized \n (except for postural stabilization)

Hyperventilation

(over-breathing): excess of CO2 \n (dizziness, blurred vision, numbness & tingling)

Hypoventilation

(under breathing): too little O2 \n (impaired cellular respiration, tissue damage, death)

In speech breathing more

hypoventilation +ventilation

breathing is a reflex from

medulla oblongata

**Motor control**

Phrenic - diaphragm (inhalation)

intercostal nerves- (inhalation + exhalation)

**Airflow**

volume of air moving through a given cross section \n of tube per unit of time

Why does air flow?

pressure difference between two points (driving pressure)

**Airflow is directly proportional to -------**

driving pressure

* (double pressure double flow)

**Resistance**

**opposition to movement**

Airflow is inversely proportional to -----

resistance

**Airflow**

**driving pressure/resistance**

half airway resistance is in ------

upper airway (nose, pharynx, larynx)

In LOWER airway 80% is in

trachea and bronchi

Sympathetic (emergency)

airway dilates, resistance lowers

Parasympathetic (conserve)

airway constricts, resistance raises

**Laminar airflow**

smooth, orderly, uninterrupted, \n directly proportional to driving pressure

* open vowel

**Turbulent flow**

irregular, disorganized, \n with little circular whirlpools (eddies)

* found in largest airways trachea
* greater driving pressure

**Elastic resistance**

work required to prevent tissue from springing back once deformed

Quiet breathing

work of breathing is \~5% of our total metabolic rate

Deep slow breathing

most of work is done against elastic resistance of tissues.

Rapid shallow breathing

most of work is done against airway resistance.

Viscosity

measure of internal friction of fluid

Friction

force that results in a drag on an object, slowing it down

**Phonation**

= sound generation by vocal fold vibration

**Larynx**

from root of tongue to trachea

* Level of C4–C6

**Pharynx**

lateral & posterior

Hypopharynx

just below pharynx

3 unpaired cartilages

epiglottis, thyroid, cricoid

3 paired cartilages

arytenoids, corniculate, cuneiform

Membranes

thyrohyoid, cricothyroid, cricotracheal

Ligaments- elasticity and movement

thyroepiglottic, hyoepiglottic, cricotracheal

Intrinsic membranes

conus elasticus + quadrangular membranes

Conus elasticus

dense fibroelastic fibers

* medial crcothyroid ligament
* lateral ricothyroid membrane (free border superiorly) = vocal ligament

Quadrangular membranes includes

superior free margins, inferior free margins, vestibule, ventricular folds, ventricles

superior free margins

aryepiglottic folds

inferior free margins

ventricular ligaments (false vocal folds)

vestibule

supraglottic space

ventricular folds

mucous membrane covering vestibular ligament + muscle

* conus elasticus

Ventricles

contain mucous glands

Functions of the larynx

airway protection, stabilize upper body during movement, phonation

Intrinsic muscles

interconnect cartilages

fine control of phonation

all paired

abduction (opening)

PCA

adduction (closing)

LCA, transverse and oblique arytenoids

Tensor (s)

* CT = pitch changer
* thyrovocalis
* medial portion of TA

Relaxor

* Thyromuscularis
* lateral portion of TA

Extrinsic muscles

* connect cartilages to external point of attachment
* includes infrahyoids (muscles of jaw and strap)
* adjust and stabalize overall laryngeal position

Adult male VF size

20 mm x 8 mm

Vocal fold histology

epithelium, lamina propria, muscle

Epithelium

stratified squamous cell

Lamina propria

superficial (reinkes space) : gelatin

intermediate : elastin

deep : collagen

Cover

Epithelium , superficial, intermediate

body

deep, vocalis muscle

Cricothyroid joint

VF elongation

Cricoarytenoid joint

VF abduction and adduction

CA joint movement that is dominant

rocking

CT muscle

pars recta (downward)

pars oblique (forward + downward)

maximal length change up to -----% resting length (CT)

25

Laryngeal innervation

cranial nerve X → Vagus

* recurrent laryngeal to all intrinsic except CT
* superior laryngeal CT

1843 Johannes Muller

myoelastic-aerodynamic theory of voice production