unit 3 respiratory Flashcards
major functions of the respiratory system
-supply body with O2 for cellular respiration and dispose of CO2
what are the 4 processes of respiration?
- Pulmonary ventilation: movement of air in and out of lungs
- external respiration: exchange of O2 and CO2 between lungs and blood
- transport: O2 and CO2 in blood
- internal respiration: exchange O2 and CO2 between blood vessels and tissues
what are the major organs of the respiratory system?
- nose and nasal cavity
- paranasal sinuses
- pharynx
- larynx
- trachea
- bronchi and branches
- lungs and alveoli
the upper respiratory system
nose, only external part of the system
functions of the upper respiratory system
- airway for respiration
- moisten and warms
- filters and cleans air
- chamber for speech
- olfactory receptors
nasal cavity characteristics
- nasal septum (R and L)
- posterior nasal apertures
- nasal vestibule: vibrissae hairs
- cells sweep contaminated mucus towards throat
- sensory nerve endings, sneeze
mucous membranes of the nasal cavity
- olfactory mucousa- olfactory epithelium
- respiratory mucousa- pseudo. ciliated columnar epidural. and goblet cells
nasal conchae
- nasal meatus
- increase mucous area
- air turbulence
- filter heat and moisten
paranasal sinuses
-ring around nose, different bones
functions of paranasal sinuses
- lighten skull
- secrete mucus
- warm and moisten air
pharynx
- throat
- connect nasal cavity and mouth to larynx and esophagus
what are the three regions of the pharynx
- nasopharynx;
- pharyngeal tonsils
- pharyngotympanic tubes - oropharynx
- isthmus of fauces
- palatine and lingual - laryngopharynx
- voice box
- either esophagus or trachea
what is included in the lower respiratory system?
- larynx
- trachea
- bronchi
- lungs
what are the two zones of the lower respiratory system?
- conducting zone: cleanses, warms and humidifies air. terminal bronchiole is end
- respiratory zone: gas exchange, respiratory bronchioles is first
Larynx
opens to lasophatynx and continuous with trachea
functions of larynx
- patent (open) airway
- routes air and food
- voice production
vocal ligaments
- true vocal chords
- vibrate
- elastic and white
glottis
opening between vocal chords
vestibular folds
- false vocal chords
- no sounds
- close opening when swallowing
trachea
windpipe
larynx to mediastinum
-divide into 2 main bronchi
what are the three layers of the trachea?
- mucosa- copse and goblet
- submucosa- mucus, C cartilage
- adventitia- connective tissue
trachealis
contract when coughing to expel mucus
carina
sensitive, when hit it causes violent coughing
bronchial tree
23 orders of branching
conducting zone to respiratory zone
structure of conducting zone
- lobar bronchus supplies to one lobe
- bronchioles: very small
- terminal bronchioles- smallest
changes of bronchi to bronchioles
- supporting structure changes
- epithelium type changes
- smooth muscle increases
respiratory zone structures
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
respiratory membrane
- blood air barrier
- alveolar and capillary walls
- fused basements membranes
- very thin for simple diffusion
what are the 4 things alveolar walls consist of?
- type I alveolar cells- SSE, flat
- type II alveolar cells- S cuboidal
- surfactant: hydrogen bonding
- antimicrobial proteins - alveolar pores- connect each alveoli
- alveolar macrophages- eat derbis on lungs
anatomy of the lungs
- each has artery, vein and bronchus
- lobules- made of alveoli
- stromata- elastic tissue that connect to make stretchy
pulmonary circulation
- right ventricle to pulm. arteries, then capillaries
- low pressure
- ACE
- exchange O2 and CO2 in blood
bronchial circulation
- systemic
- LV to RA
- high pressure
pleurae
thin, double layered that divides thoracic cavity into two pleural compartments and mediastinum
what are the three parts of the pleurae
- parietal pleura- thoracic wall
- visceral pleura- lines lung
- pleural fluid- lubricating
pleurisy
inflammation of pleurae, causing friction
- excessive fluid
- blood and filtrate to pleural effusion
two phases of pulmonary ventilation
- inspiration
2. expiration
atmospheric pressure Patm
- pressure exerted by air surrounding the body
- 760 mmHg as sea = 1 atm
intrapleural pressure Pip
- in pleural cavity
- changes with breathing
- always negative pressure
- if fluid accumulates lung can collapse
two inward forces that promote lung collapse
- lungs natural tendency to recoil, elastic
- surface tension of alveolar fluid
one outward force that enlarge lungs
-elasticity of chest wall pulls thorax outwards
intrapulmonary pressure Ppul
pressure in the alveoli
transpulmonary pressure (Ppul - Pip)
pressure that keeps lungs open
the greater, the bigger the lungs
-want Pip to be neg to inflate lungs
the lungs will collapse if?
Pip > Ppul
Pip < Patm
pulmonary ventilation
- inspiration and expiration
- lead to pressure changes
Boyles law
- Breathing
- pressure and volume of gas
- P 1/V
- P1V1 = P2V2
airway resistance
relationship between flow, pressure and resistance
F= change in P/ R
resistance in respiratory tree is insignificant because?
- diameter of airways are big
2. progressing branches of airways gets smaller and increases total cross sectional area
lung compliance
-strechey
-measure of change in lung volume
Cl = change in Vl/ change in (Ppul - Pip)
lung compliance is normally high because
- distensibility of lung tissue
- surfactant, which decreases alveolar surface tension
lung compliance can be diminished by?
- nonelastic scar tissue replacing lung tissue
- reduced production of surfactant
- decreased flexibility of thoracic cage
assessing ventilation
- volume can calculate capacities
- spirometer
inspiratory cavity
TV and IRV
what you can inhale
functional residual capacity
RV and ERV
what you can exhale, and is leftover
vital capacity
TV, IRV and ERV
everything that can be inhaled and exhaled
total lung capacity
all lung volumes
obstructive pulmonary disease
increased airways resistance
TLC, FRC, RV
hyper inflate lungs
restrictive disease
reduced FRC, RV and TLC
cant expand
caused by damaged lung
forced expiratory volume (FEV)
amount of exhaled air during a forced breath
- 1, 2 and 3
- 1 is most used, 80% is healthy
emphysema
degeneration of alveolar walls, reducing surface area for gas exchange
-caused by pollutant inhalation
asthma
swelling of airways
gas exchange
- external vs. internal respiration
1. basic properties of gasses - daltons law- parietal pressure
- henry’s law- solubility
2. composition of alveolar gas
Daltons law
- total pressure exerted
- total Patm is 760
- nitrogen 78.6%
- oxygen 20.9%
high altitude symptoms
- headaches
- shortness of breath
- nausea
- dizziness
Henry’s law
-gas in contact with liquid: each gas will dissolve in the liquid proportion to its partial pressure
depends on:
-solubility
-temperature
-partial pressure of the gases, the determining factor
decompression sickness
- buildup of nitrogen in blood
- joint pain, rash, fatigue, paralysis, death
- controlled ascent, decompression chamber, altered gasses
composition of alveolar gas
-alveoli contain more CO2 and water vapor that atmospheric
external respiration
- exchange of O2 and CO2 across membranes
- partial pressure and gas solubilities
- thickness and surface area of respiratory membrane
external respiration
- venous blood Po2= 40 mmHg
- alveolar Po2 = 104 mm Hg
oxygen transport
- 1.5 % in plasma
- 98.5 in hemoglobin
oxygen loading and unloading
- fully saturated- 104 mm Hg
- arterial blood- 98%, 100 mm Hg
- venous blood- 75%, 40 mm Hg
Bohr effect
hemoglobin oxygen binding affinity is inversely proportional to acidity and CO2
CO2 is transported in three forms?
- 7-10% dissolved in plasma as Pco2
- 20% of CO2 as carbaminohemoglobin
- 70% as bicarbonate ions
Haldane effect
I give away oxygen and take up CO2
Hyperventilation
- short rapid breaths
- decrease blood CO2 that leads to hypocapnia
influence of Pco2
most potent and closely controlled
-driving force to breathe
pulmonary irritant reflexes
protects from stretching too much
