Respiratory System

Parts

• Lungs • Air passages

Functions

• Takes in oxygen

• Removes carbon dioxide

• Body has 4-6 minute supply of oxygen

Air PassagesNose

• 2 nostrils or nares• Nasal septum

– Divides nose into 2 nasal cavities

• Lined– With mucous membrane with a rich blood supply

• Functions– Warms– Moistens– Filters

• Cilia– Tiny hair-like structures

that help move dirt trapped in mucous to the esophagus

• Olfactory Receptor– Receptors for sense of

smell

• Lacrimal Ducts– Tear ducts– Drain tears from the

eye into the nose

Olfactory Receptors

Sinuses

• Cavities in the skull that surround the nasal area

• Connected to nasal cavities by short ducts

• Function– Warms and moistens

air• Lined with mucous

membrane• Provides resonance for

the voice

Pharynx

• Throat• Lies behind the nasal

passages• 3 sections

– Nasopharynx– Oropharynx– Laryngopharynx

Larynx• Voice box• Layers of cartilage

– Largest is the thyroid cartilage commonly called the Adam's apple

• Contains– Vocal chords

• Vibrate on exhaled air to produce sound

• The tongue and lips act on the sound to produce speech

– Epiglottis• Flap of cartilage that closes the

larynx during swallowing and prevents food and liquids from entering the trachea

Trachea• Windpipe• Series of “C” shaped

cartilage to keep the tube open to the back

• Divide into the right and left bronchi

• Continues to divide into smaller bronchioles

• End in the alveoli– Air sacs

Alveoli

- One cell thick and surrounded by capillaries

- Look like a cluster of grapes

- Allow the exchange of oxygen and carbon dioxide

Surfactant

- Surfactant- Reduces surface

pressure and prevents alveoli from collapsing

Exchange of Gases

Lungs

• Right lung 3 lobes• Left lung 2 lobes due

to the heart

Pleura

• Covered by a double layer sac called the pleura

Ventilation

• Process of breathing• Diaphragm

– Muscle of respiration

– Assisted by the intercostal muscles

• Phases of respiration– Inspiration

• Inhale– Expiration

• Exhale

Diaphragm

Dome-shaped muscle that separates the thoracic cavity from the abdominal cavity

Process of Respiration

• Controlled by the medulla oblongata in the brain

• An increase in amount of CO2 in the blood , increases the rate of respiration

• Both involuntary and voluntary process

Stages of Respiration

• External Respiration– Exchange

of gases between air in the lung and the blood

Internal Respiration

– Exchange of gases between the blood and the cells

Cellular Respiration

– Use of gases to make energy, water and CO2

Diseases• Asthma

– Inflammation of airways with increased mucous production and muscle constriction

– Cause – allergen, exercise, stress, chemical

– S/S - wheezing, coughing, dyspnea, shortness of breath

– Tx - bronchodilators, steroids

Nebulizer Inhaler

Bronchitis• Inflammation of the

bronchi and bronchial tubes

• Acute – infection• Chronic – longtime

exposure to smoking• S/S productive cough,

dyspnea, fever, chest pain

• Tx – antibiotics, bronchodilators, oxygen

Emphysema

Emphysema

• Non infectious, chronic respiratory condition when walls of alveoli deteriorate and loss elasticity

• CO2 remains trapped in the alveoli

• Poor exchange of gases• S/S dypnea, feeling of

suffocation, barrel chest• TX – No cure

Epistaxis

• Nosebleed• Congested capillaries

bleed• Due to injury, blowing

too hard, hypertension

• TX – pinch nostrils lean forward slightly

Influenza

• Flu• Viral infection of the

lungs• Spread by respiratory

droplet• S/S - fever, malaise,

chills, cough, sore throat, muscle pain

• Tx - symptomatic

Lung Cancer

• Leading cause of death of men and women

• S/S no symptoms in early stages, later cough hemoptysis

• Tx – surgical removal, radiation, chemotherapy

Pneumonia• Inflammation or

infection of the lungs• Build up of exudates

(fluid) in the alveoli• S/S cough, chest

pain, fever, dyspnea• Tx – antibiotics, bed

rest, fluids, respiratory therapy, pain medication

Rhinitis, Laryngitis, Sinusitis

Tuberculosis• Infectious lung disease

caused by the bacteria Mycobacterium tuberculosis

• Can be walled off in a tubercle and become dormant

• New strains are drug resistant

• S/S fatigue, fever, night sweats, hemoptysis weight loss, chest pain

• Tx - several drugs over a period of two years