respiratory system. components: nose pharynx (throat) larynx trachea bronchi lungs alveoli (in...
TRANSCRIPT
Components:
• Nose• Pharynx (throat)• Larynx• Trachea• Bronchi• Lungs • Alveoli (in lungs)
• All parts distribute the air except the alveoli
• Alveoli exchanges air(puts it in the blood)
Functions of the respiratory system:
• to move oxygen to the lungs so oxygen can enter the blood
• To move carbon dioxide out of the blood cells to the lungs (exhaled out of the body)
• Respiration- the term for the movement of oxygen into the lungs and the release of carbon dioxide from the lungs
blood vessels
Divisions of the respiratory System:
• 1. upper respiratory tract- includes nose, pharynx, larynx
• 2. lower respiratory tract- includes trachea, bronchial tree (primary bronchi, secondary bronchi, tertiary bronchi), lungs
Components of air you breath in:
• 78-79% nitrogen• 21% oxygen• Trace amounts of
carbon dioxide
and other gases
NOSE• Mostly made of cartilage• Includes the nasal cavity
nasal cavity- extends from external opening of nose to the pharynx
The nasal cavity has 2 parts:
1. external nares- nostrils
2. internal nares- openings to the pharynx
Nasal septum- divides nasal cavity in half
-pressure on the nasal septum may cause nose bleeds called
epistaxis. It is rich in blood.
Functions of the nose:
• Mucous and nose
hairs filter the air
• Humidifies the air/moistens air (air is 100% humidified when it passes through the nose
nasal cavity infections:
• If the nasal cavity or nasal sinuses become infected by bacteria and viruses, the passages become blocked by thick mucous and it accumulates in the sinuses causing headaches.
• Treatment: use decongestants to thin the mucous allowing it to drain out and decreasing pressure
Pharynx (throat):• Connects the passage of
air from the nasal cavity to larynx
• Connects the passage of food from the oral cavity to the esophagus
Parts of the pharynx:1. nasopharynx- 1st section of pharynx
-connects to nasal cavity
-in this region, the soft palate will rise to aid in swallowing. It closes off the nasal cavity to keep things from entering it.
2. oropharynx- 2nd segment- joins nasopharynx to
laryngopharynx
-where the oral cavity empties
3. laryngopharynx- 3rd segment-
-joins oropharynx to larynx
Larynx (voice box)
– Connects to the pharynx
– Has rings on the outside made of cartilage. The largest cartilage around the larynx is the thyroid cartilage (Adam’s apple). In females, this is not as large as in males.
– Has structure called epiglottis which is a flap-like piece of cartilage that closes to keep food out of the windpipe (It stays open until swallowing occurs)
Larynx functions:
1. Connect pharynx to trachea
2. Voice box produces sound
3. Removes particles using a ciliated mucous
4. Prevents solid and liquids from entering airway
Vocal cords called glottis:• Paired ligaments
that have folds that vibrate releasing sound by moving muscle.
• The length and the tension of the cords changes which changes the voice.
Trachea:• Also called the windpipe
• Function: passes air from larynx to the 2 bronchi
• Has C-shaped cartilage on the outside to protect and prevent the collapse of it if it is hit
• Obstruction of it can cause death (oxygen can’t get to cells)
Structures in lungs:• Hilum- where bronchi, vessels,
and nerves enter the lungs
• Upon entering the lungs, the bronchi branch to form the secondary bronchi and the branch to form the tertiary bronchi (bronchioles)
• The branched bronchi is called the bronchial tree because it branches like a tree)
• Alveoli-grape-like structures at the tip of the tertiary bronchi
Alveoli:
• Probably the most important respiratory structures
• They are where gas exchange occurs – Where oxygen enters
the blood– Where carbon dioxide
exits the blood
alveoli
Blood
Thoracic cavity:• Rib cage area/chest• Also called the thorax• 3 divisions:
– Right and left pleural (contains right and left lung)
– Mediastinum (houses the esophagus, trachea, large blood vessels, heart
– Parietal layer- lines the entire thoracic cavity
Function of the thoracic cavity:
• Fluctuates in size to bring about inhalation (breathing in) and exhalation (breathing out)
Pulmonary ventilation (breathing)
Has 2 phases:1. inhale2. exhale
How occurs?• Air moves in and out due to a pressure gradient
(pressure differences in and out of lungs)• Normal air pressure is 760 mm Hg (outside lungs)• When the pressure inside lungs is less than outside
lungs, air goes in lungs (breath in/inhale)• When pressure inside lungs is higher than outside lungs,
air goes out (breath out/exhale)
Inspiration/inhalaton:
• Breathing in • How does it occur?
– The diaphragm contracts which expands the thoracic cavity (rib cage lifts and expands)
– This makes the pressure less in the lungs allowing more air to flow in from the outside
Exhalation/expiration:• Breathing out
• How it occurs?• Muscles of the ribs and the diaphragm relax• Rib cage declines to normal position which decreases
the size of the lungs• The size of the lungs decreases which increases the
pressure in the lungs pushing the air out (exhalation, expiration)
Gases of ventilation:
• Purpose of breathing is to take in oxygen and give off carbon dioxide
• Every 5 seconds, we move 500 ml of air in and out of lungs
• The air that is breathed in is made of 21% oxygen
• The body uses 7% of the oxygen which leaves 14% to breath back out. Also, the Carbon dioxide output increases by 5.6%
• This is why you can do mouth to mouth and still have enough oxygen to give to someone else
Gas Exchange in the lungs:• Gas exchange in the lungs occurs between the air in the
alveoli and the blood flowing thru the capillaries
• Oxygen enters blood blood
• Carbon dioxide leaves
blood
lungs
• Air gets to the alveoli by the following pathNose pharynxlarynx trachea primary bronchi
secondary bronchi tertiary bronchi alveoli
• Air exits the lungs by reversing the above path
Oxygen transport in the blood:
• Once oxygen enters the blood from the lungs, it has to be taken to the cells of the body
• It is transported in 2 ways:
1. some is dissolved in the plasma
2. the rest is carried by red blood cells
(these cells have hemoglobin that attaches to and carries the oxygen)
Red blood cells
Breathing reflexes:
• Cough reflex- stimulated by foreign matter in the trachea or bronchi or accumulation of excess mucous
-The glottis and epiglottis close which holds air in increasing the pressure in lungs
-The epiglottis then opens suddenly resulting in an upward thrust of air that removes the particle
Sneezing reflex:
• Stimulated by contaminates in the nasal cavity such as dust, mucous, other particles
• The same process occurs like a cough except the burst of air goes thru the nose
Hiccup reflex
• Due to spasmatic contraction of the diaphragm
• Cause unknown• The spasms cause
the glottis to close during inspiration which makes the sound
Yawn reflex:
• Unusual widening of the mouth which lets air in to the lungs
• Reason is unknown • Sometimes it is
thought to be a result of boredom (the brain wants more air to wake up)
Respiratory Disorders:
• Rhinitis- due to inflammation of the mucosa
of nasal cavity
-It is due to a virus ex. Common cold-symptoms: excessive dripping of fluid into
the lower respiratory tract or out nostrils
-this may cause sore throat, coughing or upset stomach
-the nasal lining is irritated so it may cause sneezing to clear the nose
Treatment: antihistimines and decongestants
Laryngitis:
• Due to inflammation of the vocal cords and swelling• Voice production becomes inhibited• Caused by infections, toxic fumes like smoking, vocal
abuse, and alcohol ingestion
Pharyngitis• Sore throat• Due to infection of the
pharynx due to a virus or bacteria
• Strep throat – due to infection of the streptococcus bacteria
• Treatment of pharyngitis: lozengers, rest, fluids, antibiotics, pain med.
Deviated septum
• nasal septum is off center
• Impairs proper breathing due to it being off midline
• If it is extreme, it is corrected with surgery
Bronchitis:• Inflammation of the trachea and
bronchial tree • Due to infection such as
bacteria• Excessive fluid/mucous
accumulates in bronchi and the airway seems to narrow
• Results in a lot of coughing to clear the mucous out and difficulty breathing
• Treatment: antibiotics and breathing treatments
Pneumonia:• Inflammation that affects
the airways of the lungs
• Due to infection such as bacteria, viruses, and chemicals
• Alveoli and bronchi become plugged with thick fluid (pus)
• Symptoms: coughing, breathing faster
• Treatment: antibiotics, acetaminophen, breathing treatments
Tuberculosis (TB)• Chronic infection due to
myobacterium tuberculosis
• Highly contagious• Lesions (large open
sores) occur in the lungs causing coughing, fatigue, chest pain, fever, weight loss
• Damage to the lung tissue makes the lung capacity smaller
• If treated, it can be cured
Lung cancer
• Destroys the alveoli of the lungs
• Most common cause is cigarette smoke
• Lobectomy- removal of damaged area of lung
Asthma
• Due to spasms in the
muscle of the walls of
bronchi• It narrows the airways making breathing difficult• Spasms are triggered by stress, exercise,
infection, allergic reactions• Typically inherited• Treatment: inhalers that stop muscle spasms
Emphysema
• Enlarged alveoli due to damaged lung connective tissue
• Alveoli enlarge and rupture
• Alveoli are where gases enter the blood(decreased alveoli decreases oxygen in blood)
• Symptoms: panting even with mild exertion• Due to enzymes damaging alveoli
Heimlech maneuver• Used to free foreign objects from the respiratory tract
(choking)• Places arms around the
person and thrust the fists
up into the diaphragm area• This pushes air out rapidly
which sometimes blows out
the foreign object• Problem: may break some ribs if done to hard and if can
not do it if the patient is unconscious• Use another type if unconscious