Transcript Chap 21 – Respiratory System

Chap 21 –
Respiratory
System
Learning Objectives (Part 1):
1.
Know the entire structures (and their associated functions) in
the respiratory system.
2.
Be able to explain common diseases of the respiratory system
including causes, symptoms, etc. (such as rhinitis, sinusitis,
laryngitis, pneumonia, tuberculosis, lung cancer, etc.)
Brainstorming
What are some of the deadliest lung
diseases?
Lung Cancer Kills Dana Reeves… Dead at 44
March 8, 2006 - 2:19PM
Did years of singing in smoky nightclubs kill Dana Reeve, the widow of paralysed
Superman actor Christopher Reeve? She died yesterday of lung cancer even though she
was not a smoker.
"Ten to 15 per cent of people who develop lung cancer are thought to be non-smokers. It
was said that she had, in the course of being an entertainer, spent a lot of time in pubs, in
nightclubs, in which there is a lot of cigarette smoke," said Dr James Mulshine from Rush
University Medical Centre in Chicago.
In the US more women die of lung cancer than breast cancer, and one in five American
women diagnosed with the disease have never lit a cigarette. "We know that 90 per cent of
lung cancer is linked to direct smoking, the other 10 per cent is tied to occupational
exposures, radon and secondhand smoke," said Pat McKone, a senior director of tobacco
control with the American Lung Association.
"Dana Reeve was not a smoker, but she did spend many years of her singing career in
smoke filled nightclubs.
Her death comes amid a worldwide debate on the danger of passive smoking and
attempts to ban smoking from bars, clubs and eateries.
Lung Cancer
• Accounts for 1/3 of all cancer deaths in the U.S.
• 90% of all patients with lung cancer were
smokers
• The three most common types are:
– Squamous cell carcinoma (20-40% of cases) arises in
bronchial epithelium
– Adenocarcinoma (25-35% of cases) originates in
peripheral lung area
– Small cell carcinoma (20-25% of cases) contains
lymphocyte-like cells that originate in the primary
bronchi and subsequently metastasize
Tuberculosis
• Infectious disease caused by the bacterium
Mycobacterium tuberculosis
• Symptoms include fever, night sweats, weight
loss, a racking cough, and splitting headache
• Treatment entails a 12-month course of
antibiotics
• For more on drug resistant TB:
http://www.cdc.gov/tb/pubs/tbfactsheets/mdrtb.ht
m
Pneumonia
Lungs fill with watery mucous secretions
from invasion of bacteria (or virus)
Some strains of pneumonia are very serious
and do not respond well to antibiotics
Chronic Obstructive Pulmonary
Disease (COPD)
• Exemplified by chronic
bronchitis and obstructive
emphysema
• Patients have a history of:
– Smoking
– Dyspnea, where labored
breathing occurs and gets
progressively worse
– Coughing and frequent
pulmonary infections
• COPD victims develop
respiratory failure
accompanied by hypoxemia &
carbon dioxide retention
Introduction: Functions of the Respiratory System
• Transport of O2 and CO2 between lungs &
tissues
To supply the body with oxygen and dispose of carbon
dioxide
Respiration – four distinct processes must happen:
Pulmonary ventilation – moving air into and out of the lungs
External respiration – gas exchange between the lungs and the
blood
Transport – transport of oxygen and carbon dioxide between the
lungs and tissues
Internal respiration – gas exchange between systemic blood
vessels and tissues
A Closer Look at the General Anatomy –
Major Respiratory Organs
Label your practice
diagram.
http://www.airwaycam.com/flash/fpsinterview.aspx
What Are The Structures of the Respiratory
System & What Do They Do?
Instructions: Working individually, match the structure with the function.
Write the letter of the answer. Refer to page 736.
1.
2.
3.
4.
5.
6.
7.
8.
Alveoli
Trachea
Larynx
Pleurae
Nose
Lungs
Pharynx
Bronchial
tree
a. connects trachea to alveoli
b. vital organs that house smallest passageways
c. site of gas exchange
d. cleans, warms, and moistens incoming air
e. passageway for air & food
f. area of voice production
g. houses smell receptors
h. produce lubricating fluid & compartmentalize lungs
Functions of the Nose
• The only externally visible part of the
respiratory system that functions by:
– Providing an airway for respiration
– Moistening and warming the entering air
– Filtering inspired air and cleaning it of foreign
matter
– Serving as a resonating chamber for speech
– Housing the olfactory receptors
Nose continued
• The nose is divided into two regions
– The external nose, including the root, bridge,
dorsum nasi, and apex
– The internal nasal cavity
• Philtrum – a shallow vertical groove
inferior to the apex
• The external nares (nostrils) are bounded
laterally by the alae
External Nose
Students: You don’t
have to know this
anatomy. Just
reference.
Nasal Cavity
• Lies in and posterior to the external nose
• Is divided by a midline nasal septum
• Opens posteriorly into the nasal pharynx
via internal nares
• The ethmoid and sphenoid bones form the
roof
• The floor is formed by the hard and soft
palates
Nasal Cavity continued
Respiratory mucosa
– Lines the balance of the nasal cavity
– Glands secrete mucus containing lysozyme and defensins to
help destroy bacteria
Vestibule – nasal cavity superior to the nares
– Vibrissae – hairs that filter coarse particles from inspired air
Olfactory mucosa
– Lines the superior nasal cavity
– Contains smell receptors
Nasal Cavity continued
Label your practice diagram.
Nasal Cavity continued
Label your practice diagram.
Part II – Respiratory System
Learning Objectives (part II):
3. Discuss the 3 regions of the pharynx.
4. Explain the 3 layers of the trachea as well
as the other major anatomical features.
5. Explain the special anatomy (types of
hyaline cartilage) as well as other featured
of the larynx.
6. Be able to identify & describe vocal cord
anatomy & function.
Pharynx
• Funnel-shaped tube of skeletal muscle
that connects to the:
– Nasal cavity and mouth superiorly
– Larynx and esophagus inferiorly
• Extends from the base of the skull to the
level of the sixth cervical vertebra
• It is divided into three regions
– Nasopharynx – strictly an air
passageway; closes during
swallowing to prevent food from
entering the nasal cavity
– Oropharynx - Extends inferiorly from
the level of the soft palate to the
epiglottis; common passageway for
food and air
– Laryngopharynx - Serves as a
common passageway for food and
air; lies posterior to the upright
epiglottis; extends to the larynx,
where the respiratory and digestive
pathways diverge
Trachea
• Flexible and mobile tube extending from
the larynx into the mediastinum
• Composed of three layers
– Mucosa – made up of goblet cells and ciliated
epithelium
– Submucosa – connective tissue deep to the
mucosa
– Adventitia – outermost layer made of Cshaped rings of hyaline cartilage
Trachea continued
Label your
practice
diagram.
Larynx (Voice Box)
• Attaches to the hyoid bone and opens into
the laryngopharynx superiorly
• Continuous with the trachea posteriorly
• The three functions of the larynx are:
– To provide a patent airway
– To act as a switching mechanism to route air
and food into the proper channels
– To function in voice production
Larynx continued
• Cartilages (hyaline) of the larynx
– Shield-shaped anterosuperior thyroid cartilage
with a midline laryngeal prominence (Adam’s
apple)
– Signet ring–shaped anteroinferior cricoid
cartilage
– Three pairs of small arytenoid, cuneiform, and
corniculate cartilages
• Epiglottis – elastic cartilage that covers the
laryngeal inlet during swallowing
Framework of the Larynx
Label your practice diagram.
Vocal Cords
• http://www.voicedoctor.net/media/video/index.html
Diagnosis Laryngitis
We know the familiar symptoms…
hoarseness, loss of vocal abilities, etc.
Maybe you talked too much or screamed for
your favorite team…
What is really going on?