Transcript Respiratory system

Joe Pistack MS/ED
 Respiratory
system contains:
 Upper respiratory tract.
 Lower respiratory tract.
 Upper
respiratory tract contains:
 The nose
 The nasal cavities
 Pharynx
 Larynx
 Upper trachea
 Lower
respiratory tract:
 Lower trachea
 Bronchi
 Bronchioles
 Alveoli
 Nose-includes
an
external portion
that forms part of
the face.
 Nasal
cavitiesseparated into
right and left
halves by a nasal
septum.
 Air
enters the nasal
cavities through two
openings called
nostrils.
 Nasal
hairs in the
nostrils filter large
particles of dust
that would
otherwise be
inhaled.
 Nasal
conchae-three
bony projections
appear on the
lateral walls of the
nasal cavities.
 Support mucous
membrane.
 Contains blood
vessels and mucoussecreting cells.
 Paranasal
sinuses:
 Maxillary sinuses
 Frontal sinuses
 Ethmoidal sinuses
 Sphenoidal sinuses
 Mucous
from the
paranasal sinuses
drain into the
nasal cavity.
 Deviated
septumNasal septum bends
to one side or the
other.
 Obstructs
flow of
air, makes breathing
difficult.
 Surgical
repair is
called a septoplasty.
 Pharynx
or throatLocated behind
the oral cavity,
between the nasal
cavities.
 Includes three
parts:
 Nasopharynx
 Oropharynx
 laryngopharynx
 Nasopharynx-upper
section.
 Oropharynx-middle
section.
 Laryngopharynx-lower
 Function
section.
of pharynx:
 Conducts food toward the esophagus.
 Functions as a passageway for both food and
air.
 Also
called the
voicebox
 Three functions:
(1)Passageway for air
during breathing
(2)Produces sound
(3)Prevents food and
foreign objects from
entering the trachea
 Triangular
structure
made primarily
of cartilage,
muscles,and
ligaments.
 Thyroid
cartilage-largest of the cartilaginous
structures .
 Protrudes
in the front of the neck as the
Adam’s apple.
 Epiglottis-located
at the top of the larynx,
acts as a flap, covers the opening of the
trachea during eating so that food doesn’t
enter the lungs.
 Folds
of tissue
composed of
muscle and elastic
ligaments covered
by mucous
membrane.
 The
space
between the vocal
cords is the
glottis.
 False
vocal cords-do
not produce sounds.
 True
vocal cordsproduce sound, air
flowing from the
lungs through the
glottis during
exhalation causes the
vocal cords to vibrate
producing sound
 The
loudness of your voice depends on the
force with which air moves past the true
vocal cords.
 The
pitch of your voice depends on the
tension exerted on the muscles of the true
vocal cords.
 You
form words with your pharynx, oral
cavity, tongue and lip movement.
 Swallowing
plays a key role in preventing
food or water from entering into the
respiratory tubes.
 Neurological
patients who have difficulty
swallowing are at risk for aspiration.
(entrance of food or water into the lungs)
 Windpipe-tube
4
to 5 inches in
length and 1 inch
in diameter.
 Extends from the
lower edge of the
larynx downward
into the thoracic
cavity where it
splits into the right
and left bronchi
 Carina-point
where
the trachea splits, at
the manubriosternal
junction (where the
manubrium of the
sternum meets the
sternal body)
 This area is very
sensitive, touching
during suctioning
causes vigorous
coughing.
 Insertion
of a tube
through a surgical
incision into the
trachea below the
level of an
obstruction.
 By passes the
obstruction and
allows air to flow
through the tube
into the lungs.
 Lies
in front of the esophagus, the food tube.
 C-shaped
rings of cartilage partially surround
the trachea for its entire length.
 The
rings are open on the back side of the
trachea so that the esophagus can bulge
forward as food moves along the esophagus
into the stomach.
 Without
the cartilaginous rings, the trachea
would collapse and shut off air supply.
 Consists
of :
 Bronchi
 Bronchioles
 Alveoli
 Resembles
an upside down tree.
 Right
and left
primary bronchi
are formed as
the lower part
of the trachea
divides into two
tubes.
 Primary
bronchienter the lungs at
a region called the
hilus.
 Primary
bronchi
branch into
secondary bronchi,
which branch into
smaller tertiary
bronchi.
 Left
bronchus is
narrower because
the heart lies to
the left side of
chest.
 Right
bronchus is
shorter and wider
and extends
downward in a
vertical direction.
 The
bronchi divide
repeatedly into
smaller tubes
called bronchioles.
 Regulate
the flow
of air to the
alveoli.
 Contraction
of the
bronchiolar smooth
muscle causes the
bronchioles to constrict,
this decreases the
bronchiolar lumen and
decreases the flow of
air.
 Relaxation causes the
lumen to increase,
thereby increasing the
flow of air.
 Small
grape-like
structures, tiny air
sacs that form at
the ends of the
respiratory
passages.
 Function is to
exchange oxygen
and carbon dioxide
across the alveolarpulmonary capillary
membrane.
 Certain
respiratory diseases cause thickening
of the alveolar wall.
 Results
in slow exchange of gases.
 Results
in hypoxia, retained carbon dioxide,
this results in acidosis ( disturbance in acidbase balance).
 Ex.
Emphysema, this may result in clubbing
of the fingers and toes.
Amazing
Facts:
 10,000
liters of air per day goes through our
lungs - that’s 2650 gallons
 There
 Have
are about 300 million alveoli (300,000,000)
the surface area of a tennis court - that’s
about 2800 square feet.
 Clubbing:
 Enlarged
fingertips
and toes.
 Changes in thickness
and shape of the
nails.
 Due to formation of
additional
capillaries in
attempt to deliver
oxygen.
 Two
lungs:
 Located in the
pleural cavity.
 Extend from area
above the clavicles
to the diaphragm.
 Soft, cone-shaped,
occupy most of the
space in the
thoracic cavity.
 Subdivided
into
lobes:
 Right lung has
three lobes:
superior
middle
inferior
Left lung:
superior
inferior
 Upper,
rounded part
is called , the apex.
 The
base rests on
the diaphragm.
 Amount
of air lungs
can hold depends on
build, age, and
physical condition.
 Pleura-lining
of
the inner chest
wall, continuous
serous membrane.
 Visceral-inner
layer.
 Parietal
pleuraouter layer.
 Expanded
lungs
normally fill the
thoracic cavity.
 Tendency
of the lungs
to collapse is due to
two factors:
 Elastic
recoil
 Alveolar surface
tension
 Negative
intrapleural
pressure is eliminated,
lungs collapse.
 Lungs
need to be expanded to function
properly.
 Elastic
recoil opposes lung expansion.
 Negative
intrapleural pressure must exceed
the elastic recoil and surface tension.
 Ex.
balloon
 High
surface tension within the alveoli is
favorable for a collapsed lung.
 Surfactant
 Problem
decreases surface tension.
with preterm infants, not enough
surfactant is secreted so they have difficulty
breathing. Rx. Steroids.
 Intrapleural
pressure remains negative when no
holes exist in the chest wall.
 When
the lungs expand, the diaphragm
contracts, the pull causes negative pressure.
 Anything
that collects in the intrapleural space
can collapse the lung. Ex. blood, air, and
drainage.
A
knife wound would eliminate intrapleural
pressure.
 Respiration
includes:
 (1)-ventilation
 (2)-exchange
or breathing
of oxygen and carbon
dioxide
 (3)-transport
of oxygen and carbon
dioxide by the blood
 Ventilation-movement
of air into and out of
the lungs.
 Two


phases:
Inhalation-breathing-in phase
Exhalation-breathing-out phase
 Respiratory
cycle-one inhalation and one
exhalation .
 Dependent
on Boyle’s law, “As volume
increases, pressure decreases; as
volume decreases, pressure increases.”
Thoracic pressure decrease causes air to
move through the nose and into the
lungs.
Thoracic pressure increase causes air to
move out of the lungs. When
respiratory muscles relax, they
decrease thoracic volume.
 Change
in thoracic volume is due to the
contraction and relaxation of the respiratory
muscles.
 On
inhalation-respiratory muscles, (the
diaphragm and intercostal muscles) contract.
 Diaphragm
 Accessory
is the chief muscle of inspiration.
muscles of respiration-muscles of
the abdominal wall and internal intercostal
muscles.
Exchange of gases occurs at two sites:
 (1)lungs
 (2)cells


In lungs, oxygen diffuses from the alveoli into
the pulmonary capillaries. Carbon dioxide
diffuses from the pulmonary capillaries into the
alveoli.

In the cell, oxygen diffuses from the capillaries
into the cells, carbon dioxide diffuses from the
cells into the capillaries.

Blood transports oxygen and carbon dioxide.
 Different
names.
volumes of air we breathe have
 Four
pulmonary volumes:
 (1)-tidal volume
 (2)-inspiratory reserve volume
 (3)-expiratory reserve volume
 (4)-residual volume
A
spirometer is used to measure pulmonary
volumes.
 Tidal
volume-the amount of air moved in and
out of the lungs with each breath. Usually
about 500ml.
 Inspiratory
reserve volume-in addition to the
normal volume, any extra air that you can
breathe in. Approximately 3000ml.
 Expiratory
reserve volume-the normal
amount of air you exhale plus any extra,
usually about 1100ml.
 Residual
volume-after forced exhalation,
about 1100ml of air remains in the lungs.
The remaining air is the residual volume.
 Residual
air remains in the lungs at all times,
even between breaths.
 Anatomical
dead space-some air that you
inhale never reaches the alveoli, it is not
available for gas exchange.
 Normal
breathing is rhythmic and
involuntary.
 Normal
respiratory rate is 12 to 20 breaths
per minute in an adult.
 In
a child, normal respiratory rate is 20 to 40
breaths per minute.
 Medullary
respiratory control center-main
control center for breathing, located in the
medulla, sets the basic breathing rhythm.

Pneumotaxic center and apneustic center-located in
the pons, modify and help control breathing patterns

Opioids, such as morphine, depress respiratory
function, do not administer without checking
respirations.

Hering-Breurer Reflex-reflex that prevents
overinflation of the lungs.

Hyperventilation-increase in the rate and depth of
respirations. Causes excess exhaling of carbon
dioxide and produces hypocapnia (diminished carbon
dioxide in the blood).
 Hypoventilation:
 Decrease
in the amount of air entering the
alveoli.
 Causes
insufficient amount of oxygen and
excessive amount of carbon dioxide in the
blood.
 Causes
are respiratory obstruction - lung
disease, deformity of the chest, mucous plug.
 Exhalation:
 Occurs
when the respiratory muscles relax,
allowing the thorax to return to smaller, resting
thoracic volume.
 Muscles
of respiration contract in response to
stimulation of the phrenic and intercostal
nerves.
 Inhalation
delivers fresh oxygen-rich air to the
alveoli, and exhalation removes carbon dioxidelaiden air from the alveoli.
 The
exchange of gases occurs at two sites:
 The lungs
 The cells
 Gas
exchange occurs in the lungs, specifically
across the membranes of the alveolus and
the pulmonary capillary.
 Three
conditions make alveoli suited for
exchange: (1) Large surface area, (2)Thin
alveolar and capillary walls, (3)Closeness of
the alveoli to the pulmonary capillaries.
 Lung
capacity decreases.
 Protective mechanisms of respiratory disease
decline.
 Number of alveoli diminishes resulting in
decreased oxygenation.
 Decreased oxygenation decreases the amount
of physical activity that the person is capable
of.
 Lungs show wear and tear from a lifetime of
inhaling harmful substances such as pollens,
pollutants, cigarette smoke.
 apnea-temporary
cessation of breathing.
 Dyspnea-difficult
or labored breathing.
 Tachypnea-rapid
 Eupnea-normal,
breathing.
quiet breathing.
 Orthopnea-difficult
breathing that is
relieved by sitting-up position. Usually
dyspnea is relieved with two pillows.
 Cheyne-Stokes
respirations-an irregular
breathing pattern characterized by a series
of shallow breaths that gradually increase in
depth and rate. A period of apnea lasting 10
to 60 seconds follows, the cycle then
repeats.