Transcript The Respiratory System

The Respiratory System
Chapter 10
The Respiratory System
• _________ Respiratory Tract (structures outside of the
lungs)
• Nostrils
• Nasal passages
• Pharynx
• Larynx
• Trachea
• _________ Respiratory Tract (structures within the lungs)
• Bronchi
• Bronchioles
• Alveolar ducts
• Alveoli
Intro to the Respiratory System
• The primary function of the respiratory
system is to bring ___________ into the
body and to carry _________ __________
out of body.
• Respiratory system works together with
the cardiovascular system!
• Secondary functions:
• Phonation (voice production)
• Regulation of body temperature
• Regulation of acid-base balance
• Sense of smell
Two types of Respiration
• ____________ Respiration
• Occurs in capillaries of pulmonary circ.
• Is the exchange of oxygen and carbon
dioxide between the air that is inhaled
into the lungs and the blood flowing
through the pulmonary capillaries.
• ____________ Respiration
• Occurs in capillaries of systemic circ.
• Is the exchange of oxygen and carbon
dioxide between the blood in the
systemic capillaries and all of the cells
and tissues of the body.
• Also called ____________.
• Begins in the larynx (voice box).
Voice Production
• Two bands called the _______
_______ (or vocal folds)
stretch across the lumen of the
larynx and vibrate as air
passes over them.
• Thorax, nose, mouth, pharynx,
and sinuses may contribute to
the vocal sounds.
Body Temperature Regulation
•
Cold conditions:
• Superficial blood vessels under the epithelium of the nasal passages helps warm
inhaled air before it reaches the lungs.
• Keeps chilled air from circulating through the lungs and causing hypothermia.
•
Hot Conditions:
• Aids in cooling through panting.
• Rapid respiration movements caused during panting cause increased
evaporation of fluid from the lining of the respiratory passages and mouth,
which helps to cool the blood vessels under the epithelium.
Acid Base Balance
• Important homeostatic mechanism in the body.
• Lower the pH, the more _________ the environment
• Higher the pH, the more _________ the environment.
• Normal pH of the blood is ______ (acceptable range of 7.35-7.45).
• CO2 (carbon dioxide) is considered an acid in
the bloodstream.
• The higher the CO2, the lower the blood pH, the
more acidic the blood.
• Respiratory system can alter CO2 content in the
blood by adjusting how fast air is breathed in and
out.
Sense of Smell
•
Also called the _________ sense.
•
Many animals have less sensitive eyesight
than humans, but a highly sensitive sense of
smell.
•
Receptors are contained in two patches
of sensory epithelium located up high in
the nasal passages.
•
Olfactory cells are mixed with supporting
cells in the patches.
•
Hairlike processes of the olfactory cells
project up into the mucous layer that covers
the nasal epithelium
•
When odor molecules dissolve in the mucus
and contact the sensory processes, nerve
impulses are generated that travel to the
brain and are interpreted as smells.
Upper Respiratory Tract
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Nostrils
Nasal passages
Pharynx (throat)
Larynx (voice box)
Trachea (wind pipe)
The Nose
• ____________: nostrils; external openings of
the respiratory tube
• ___________ ______________: between the
nostrils and pharynx
• Nasal __________- separates the left nasal
passage from the right
• Hard and Soft __________- separate the nasal
passages from the mouth.
• Contain _____________ (nasal conchae): thin,
scroll-like bones covered with nasal epithelium that
occupy most of the lumen of the nasal passages.
• 2 sets (dorsal and ventral) that divide each
nasal passage into 3 main passageways
• Each passageway is called a ____________.
• Ventral, middle, dorsal and common
Lining of the nasal passages
• Lined with _____________
_____________ epithelium
• _________ project from the cell
surfaces up into a layer of mucus
• Mucus is secreted by
_________ cells.
• Extensive complex of large blood
vessels lies just beneath the nasal
epithelium.
• _____________ of the nasal passages that are contained within spaces in
certain skull bones.
• Each sinus is named after the skull bone that houses it.
• Most animals have two _________ sinuses and __________ sinuses.
• Sinuses have same ciliated lining as the nasal passages. Cilia keep fluid
and debris from accumulating in sinuses and obstructing the openings of
the nasal passages by sweeping it down into the nasal passages.
Sinuses
• Inflammation of the sinuses. Due to infection, allergies, tumors,
etc.
• Openings into nasal passages swell shut or become clogged with
inflammatory debris
• Fluid in sinuses cannot be passed → ↑pressure → pain
• Build up of pressure can be very uncomfortable for the animal.
•
• Can be treated with antibiotics and decongestants, but if
ineffective, a hole may need to be drilled into the sinus to allow
drainage.
Sinusitis
• Common passageway for both _____________ and _____________
systems.
• Rostral end is divided into:
• _______pharynx (respiratory passageway, dorsal)
• _______pharynx (digestive passageway, ventral)
• Divided by the soft palate
• Caudal end is divided into:
• ___________ (digestive passageway, dorsal)
• ___________ (respiratory passageway, ventral)
Pharynx (Throat)
Larynx
• Commonly called the “voice box”
•
• Short, irregular tube that connects
the _________ with the trachea.
• Made of segments of ___________
that are connected to each other and
the surrounding tissues by muscles.
• Supported by the hyoid bone.
• Cartilage components: *epiglottis,
*arytenoid cartilages, thyroid
cartilage, cricoid cartilage
Laryngeal Cartilages
• Epiglottis
• Single, leaf-shaped; projects forward from the ventral portion of
the larynx
• During swallowing, the epiglottis is pulled back to cover the
opening of the larynx
• Arytenoid cartilages
Laryngeal
Cartilages
• Paired; attachment site of the vocal
cords
• Muscles adjust the tension of the
vocal cords by moving the cartilages.
• Lessening tension of the vocal
cords allows for __________
pitched sounds.
• Tightening of the vocal cords
allows for _________ pitched
sounds.
• Arytenoid cartilages and the vocal
cords form the boundaries of the
_________-the opening into the
larynx.
Laryngeal Cartilages
• Thyroid cartilages
• Shaped as a V that forms and supports the ventral portion of the larynx.
• Cricoid cartilage
• Ring-shaped, helps form and support the caudal portion of the larynx.
Breathing and Swallowing
• Because it is a common passageway that
must allow both breathing and swallowing,
delicate reflexes control the actions of the
muscles around the pharynx
• Larynx and pharynx work together to prevent
swallowing from interfering with breathing
and vice versa.
• Swallowing:
• Breathing stops
• Opening to the larynx is covered (by
epiglottis)
• Moving of material to be swallowed to rear of
pharynx
• Esophagus opens and material moves into it
• Larynx reopens when epiglottis lays down
• Breathing resumes
Coughing
• Cough is generated behind a closed glottis.
• Breathing muscles contract, compressing the
thorax.
• Builds pressure behind the closed glottis.
• When glottis suddenly opens, the forceful
release of air results in a cough.
• Purpose of coughing is to clear mucus and
other matter from lower respiratory
passages.
• **Closure of glottis also occurs when
straining (lifting, defecation, urination,
parturition)
• __________- similar to a cough, but originates in the nasal passages, burst
of air is directed through the nose and mouth in effort to eliminate the
irritant.
• __________- slow, deep breath taken through a wide-open mouth. May be
stimulated by slight decrease in oxygen levels, drowsiness, fatigue, and
boredom.
• __________- slightly deeper than normal breath. May serve to expand
lungs more than normal. May hear “sighing” patient under anesthesia.
• __________- spasmodic contractions of the diaphragm accompanied by
sudden closure of the glottis. Usually self-limiting
Other terms
Endotracheal Intubation
• Process in which an endotracheal tube is
placed through the glottis to the trachea.
• May be helped by the use of a
laryngo________- an instrument that
helps to hold down epiglottis.
• Done blindly in large animals
• Laryngo_________ –reflex commonly
seen in cats, when glottis is touched,
larynx slams shut.
Aspiration Pneumonia
• Inflammation of lung tissue due to
inhalation of foreign material
• OFTEN FATAL
• Causes (easier to prevent than to treat):
• _______ _________given too quickly
• ______________ procedure
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Animal loses gag reflex
Head at same level as stomach
Protect with endotracheal tube cuff
NPO 12 h before Sx
Laryngeal Hemiplegia (Roaring)
•
Usually a congenital degeneration of the nerve that supplies the muscles that
tighten the arytenoid cartilage (usually left).
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At rest usually does not cause a problem
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When animal exercises, may result in obstruction of the _________ as it “flaps in
the wind” when the animal breathes, causing a roaring sound and _____________
intolerance.
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Common treatments include prosthetic laryngoplasty “tie back” or
ventriculectomy/cordectomy