Section 11.1 The Function of Respiration RESPIRATORY SYSTEM – the group of organs that provides living things with oxygen from outside the body and disposes of waste products such as carbon dioxide

- Ensures that oxygen is brought into the body and made available to all cells that need it, and carbon dioxide can leave cells and be removed from the body

RESPIRATION – all the processes involved in bringing oxygen into the body, making it available to each cell, and eliminating carbon dioxide as waste

RESPIRATORY AND GAS EXCHANGE- Several stages, each stage has specialized structures to facilitate it

Breathing External respiration Internal respiration Cellular respiration

- First stage (Breathing): involves two basic processes: inspiration (breathing in, inhaling) and expiration (breathing out, exhaling)

INSPIRATION – action of drawing oxygen rich air into the lungsEXPIRATION – action of releasing waste air from the lungs

- Inspiration moves air from outside the body into the lungs inside the body- Expiration moves air from lungs back outside the body

- Second stage (external respiration): exchange of oxygen and carbon dioxide between the inspired air inside the lungs and blood

- Vital function of gas exchangeGAS EXCHANGE – transfer/delivery of oxygen from inhaled air into the blood, elimination of carbon dioxide from blood into lungs, primary function of lungs

- Third stage (internal respiration): exchange of oxygen and carbon dioxide between blood and body’s tissue cells

- Fourth stage (cellular respiration): series of energy releasing chemical reactions that take place within cells, sole means of providing energy for all cellular activities

RESPIRATORY SURFACES- Two main requirements for respiration

Respiratory surface must be large enough for the exchange of oxygen and carbon dioxide to occur quickly enough to meet the body’s needs

Respiration must take place in a moist environment so oxygen and carbon dioxide are dissolved in water

RESPIRATORY SURFACE – area of an animal’s body where gases are exchanged with the environment

- Some animals exchange gases through their outer body surface, gills or trachea

- As with nutrients, gases involved in respiration are transported to and from the cells throughout the body by the circulatory system

- All organisms use ventilation to increase the efficiency of respirationVENTILATION – the process of drawing, or pumping, an oxygen containing medium (water or air) over a respiratory surface (gills, trachea, lungs)

TYPES OF RESPIRATORY SURFACES IN ANIMALSDescription of Respiratory Surfaces ExampleOuter Skin

- Animals (Ex. Earthworms) don’t have specialized gas exchange organs

- Use their outer skin as a respiratory surface

- Oxygen diffuses into a network of thin walled capillaries below the skin, carbon dioxide diffuses out

- Animals that breathe though their skin usually have a high ratio of respiratory surface to body volume

- Must live in damp places or in water to keep their respiratory surface (skin surface) moist

- Amphibians

Gills- Fish, aquatic invertebrates, clams,

mussels, crayfish, crabs exchange gases through gills

- Gills are the extensions or folds in the body surface that increase that increase the surface area through which gases are exchanged

- Oxygen in water diffuses across gill surfaces into capillaries, carbon dioxide diffuses out into the external environment

- Surrounded by water, therefore respiratory surfaces are always moist

Tracheal System- Insects exchange gas through a

tracheal system, internal system of branching respiratory tubes called tracheae

- Tracheae connects body cells directly to the environment outside of the insect’s body by smaller tubes called spiracles

- Oxygen enters body through the spiracles, then diffuses into the tracheae

- Carbon dioxide diffuses out of the body in the opposite direction

- Insect’s circulatory system not involved in transporting oxygen, gas is exchanged directly with the body cells

Lungs- Due to large size and higher

activity levels, most land animals need large amounts of oxygen that can’t be delivered by gills or a tracheal system

- Mammals, birds, reptiles, most amphibians exchange gases through an internal respiratory system

- Consists of trachea (windpipe) that branches into lungs

- Lungs are sacs lined with moist epithelium

- Folds in lung lining increase the surface area for diffusion

- Oxygen diffuses across epithelium into capillaries

- Carbon dioxide diffuses in the opposite direction into external environment

GAS EXCHANGE IN AQUATIC ENVIRONMENTS- Aquatic environments contain oxygen in the form of dissolved gas- Fish, lobster, clams, molluscs take in oxygen through gills

GILLS – physical adaptations that enable organisms to carry out gas exchange in aquatic environments

- Fish exchanges gas by taking water into its mouth, then ventilating (pumping) it over the gills

- As water flows across the gills, dissolved oxygen in the water diffuses, from high concentration (water) to low concentration (blood), into the blood circulating through the surrounding capillaries

- Carbon dioxide diffuses from the blood across the gill tissue, intro the water and is carried out of the fish’s body as water passes out of the gill openings

- Fish also have a counter current exchange mechanism: oxygen diffuses along a gradient (diffusion gradient)

DIFFUSION GRADIENT – describes the relationship in which a dissolved substance moves from a region of high concentration to a region of low concentration

- Blood and water flow in opposite directions, thus the diffusion gradient of oxygen is kept high

GAS EXCHANGE ON LAND, MECHANICS OF BREATHING- Air breathing vertebrates (Ex. Reptiles, birds, mammals) rely on lungs for gas

exchange- These vertebrates have a specialized system in their respiratory system that

provides a passage for air to move from outside to inside the body, where gas exchange occurs

- Air doesn’t flow in/out of the lungs on its own- Brain acts as a respiratory control centre to co-ordinate breathing

movements, regulate breathing rate, monitors the volume of air into the lungs, monitors gas levels in blood

- Two sets of structures: muscular diaphragm and rib muscles, control the air pressure inside the lungs

- Changes in air pressure causes air to move in/out of lungsDIAPHRAGM – dome shaped sheet of muscle that separates the region of lungs (thoracic cavity) from the region of stomach and liver (abdominal cavity)

- Rib muscles (intercostal muscles) found between ribs and along the inside surface of the rib cage

AIR PRESSURE IN THE LUNGS- Regular signals from the brain triggers the diaphragm and intercostal muscles

to work together at the same time, thus causing air to move in/out of the lungs

- Air pressure within lungs is controlled by these 2 structures- Inhalation begins when external intercostal muscles and diaphragm contract;

diaphragm moves down- This expands rib cage upwards and outwards, floor of chest cavity moves

downward- Chest cavity is airtight, thus its volume increases- Increase in volume means the same amount of air contained in a larger space

- When molecules of a gas are moved father apart (as they are when volume of the chest cavity increases), gas molecules exert less outward pressure, thus air pressure in thoracic cavity decreases

- Lungs are suspended in the chest cavity, sensitive to changes in the air pressure of the cavity

- As air pressure in the cavity decreases, walls of lungs are drawn outward into the chest cavity and the lungs expand

- Expansion causes air pressure in the lungs to be lower than the air pressure outside of the body

- Since air moves from regions of higher pressure to regions of lower pressure, air rushes into the lungs from the external environment

- Opposite muscle movements expel air from lungs- Exhalation starts when diaphragm and rib muscles relax, volume of chest

cavity and lungs decreases, air pressure inside lungs increases, air moves from lungs to lower pressure environment outside the body

- Change in air pressure causes air to move from an area of high pressure (lugs) to an area of lower pressure (outside the body)

THE SPIROGRAPHSPIROGRAPH – graph representing the amount (volume) and speed (rate of flow) of air that is inhaled and exhaled, measured by a spirometer

- Represents the amount of air that moves in/out of the lungs with each breathTIDAL VOLUME – volume of air inhaled and exhaled during normal breathing movement when the body is at restINSPIRATORY RESERVE VOLUME – the additional volume of air that can be taken into the lungs beyond a tidal inhalation

EXPIRATORY RESERVE VOLUME – additional volume of air that can be forced out (expelled) from the lungs beyond a tidal exhalationVITAL CAPACITY – total maximum volume of air that can be moved in/out of the lungs during a single breath (tidal volume + inspiratory reserve volume + expiratory reserve volume)RESIDUAL VOLUME – volume of air that remains in the lungs/passageway after a complete exhalation

- This gas never leaves the respiratory system, if it did, lungs/respiratory passageways would collapse

- Residual volume has little value for gas exchange because it isn’t exchanged with air from outside the body

SECTION 11.2 – THE HUMAN RESPIRATORY SYSTEM: A CLOSER LOOK

- Humans: lungs are the main organs of respiration- Respiratory tract is a passage necessary for air to move from outside the body

to the respiratory surface inside the body

THE PASSAGE OF AIR THROUGH THE UPPER RESPIRATORY TRACT- Air enters respiratory system through nostrils, can also enter through mouth

especially if breathing is rapid- Air is warmed and cleansed of dust/small particles inside the nasal passages

at the back of the nose- Thin bones, turbinate bones, project into the nasal passages and increase

the surface area of these chambers- Thin membrane covering the turbinate bones secretes mucus, moistens air

and traps particle of dust, bacteria, other foreign matter- Ciliated cells found in the membrane have waving hair-like projections that

move the trapped particles into the nose or throat where they can be expelled by sneezing/coughing

- Dense network of capillaries in lining of turbinates supplies warm blood to the nasal passages, heats air in nasal passages to body temperature, protects delicate structures in the lower respiratory tract from damage by cold air

- Warm, cleaned, moist air passes from the nasal passages through the pharynx (throat)

PHARYNX – passageway just behind the mouth that connects the mouth and nasal cavity to the larynx and esophagus

- Base of pharynx, behind the tongue, is the entrance to the trachea (windpipe)

TRACHEA – tube that carries air from the nasal passages or mouth to the bronchi, and then to the lungs

- Opening of the trachea is called the glottis GLOTTIS – opening of the trachea through which air enters the larynx

- Glottis can be closed by the epiglottis, which is normally upright to allow air to pass freely into the trachea

- When you swallow food, epiglottis covers the glottis to prevent food from entering the trachea into the lungs

THE LARYNX - Between the glottis and trachea, air passes through larynx (voice box)

LARYNX – structure between glottis and trachea that contains vocal cords- Structure is made of cartilage, rough, firm connective tissue- Larynx used for producing sound in mammals- Vocal cords consist of 2 folds of membrane stretched across the larynx- During normal breathing, muscular tissue holds vocal cords apart, air passes

freely through larynx - To make sounds, vocal cords move closer together so the pressure from air

expelled from the lungs causes the cords to vibrate- Pitch of sound varies with length of the vocal cords- Long cords produces a long sound, Shorter cord produces a higher sound- At puberty, vocal cords of males grow quickly, often causes “breaking” quality

in voice- Breaking sound disappears once the vocal cords are finished growing - Air moves down trachea after passing through the larynx- Flexible tube is strengthened and held open by semicircular loops of cartilage- Trachea: 10-12cm in length, runs from throat to middle of chest, then splits

into 2 branches

LOWER RESPIRATORY TRACT- 2 tubes that branch from the trachea called bronchi (singular bronchus)

BRONCHUS – passageway that branches from the trachea to the lungs- One bronchus enters each lung- Humans: lungs divided into regions called lobes- Right lung has 3 lobes, left lung has 2 to leave space for the heart in the

thoracic cavity- Each lung surrounded by a thin, flexible, double layered sac called pleural

membrane - Outer layer of this membrane attached to the inside of the chest wall, inner

layer covers lungs - Thin space between these 2 layers contains lubricating fluid that allows layers

to slide easily against each other during the movements of breathing - Inside lungs, each bronchus subdivides many times to form bronchioles

BRONCHIOLES – the passageway that branches from each bronchus inside the lung into increasingly smaller thin-walled tubesALVEOLI – (alveolus) tiny sac, with a wall that is one cell thick, found at the end of a bronchiole; respiratory gases are exchanged in this sac

- Estimated 500 million alveoli in an average adult human lung- Network of fine capillaries and walls of alveoli are only one cell thick- Must have thin membranes so that the respiratory/circulatory system can

interact; oxygen from air diffuses into the blood and carbon dioxide from the blood diffuses into the lungs

DETAILED LOOK AT GAS EXCHANGE IN HUMANS

- During external respiration, thin walls of alveoli and capillaries allow gases to diffuse through their cell membranes easily

- Air that enters the alveoli after inhalation has a higher concentration of oxygen than the blood in the capillaries next to the lungs (oxygen in blood in capillaries has diffused out of the tissue cells)

- Oxygen diffuses out of the alveoli into the blood in the capillaries- Blood in the capillaries has a higher concentration of carbon dioxide than the

air in the alveoli as blood that diffuses into the capillaries is returning from the body tissue cells

- Thus carbon dioxide diffuses into the alveoli fro the capillaries- Carbon dioxide is exhaled into air

- Once oxygen and carbon dioxide exchange has occurred between the capillaries and alveoli, blood in the capillaries goes back to the heart then to the tissue cells

- Oxygen diffuses from the blood into the tissue cells and is exchanged for carbon dioxide once again

HOW BLOOD TRANSPORTS RESPIRATORY GASES- During respiration, both oxygen and carbon dioxide are transported through

the bloodstream- 99% of oxygen that reaches cells is carried by hemoglobin

HEMOGLOBIN – an iron containing protein found in red blood cells, which binds to and transports oxygen from the lungs to the rest of the body

- 1% dissolved in the watery blood plasma- When carbon dioxide leaves tissue cells and diffuses into the capillaries, it

enters the red blood cells- 23% of carbon dioxide is carried in the blood by hemoglobin- 77% carried by blood fluids- When carbon dioxide reaches the lungs, it diffuses into the air in the alveoli

and is exhaled

11.3 RESPIRATORY SYSTEM DISORDERS- Similar to the digestive system the respiratory system links the internal

environment of the body with the outside environment- Quality of both environments plays a key role in the health of the respiratory

system– Changes outside the body can influence how well the respiratory system

functions and how well the whole body functions

DISORDERS OF THE UPPER RESPIRATORY TRACT- Most common throat ailments caused by viruses and bacteria carried in the

airTONSILLITIS – an infection of the tonsils caused by a virus or by bacteriaTONSILS – 2 oval shaped organs located in the pharynx at the back of the throat

- Function of tonsils to help prevent bacteria and other harmful substances from entering the respiratory system

- Symptoms: red, swollen tonsils, sore throat, fever, swollen neck glands- Tonsils are naturally large in children but shrink with age- Severe tonsillitis treated surgically by removing all or part of the tonsils- Removing tonsils can increase the risk of throat infections later in life

LARYNGITIS – inflammation of the larynx that can cause the voice to be raspy or hoarse, caused by infection, allergy or overstraining the voice (prolonged yelling)

- Larynx contains vocal cords- When larynx is inflamed, vocal cords cannot vibrate as they usually do, thus

people may lose their voice or speak in a hoarse whisper- Not serious, clears up on its own after a few days

DISORDERS OF THE LOWER RESPIRATORY TRACT- Can damage the bronchi and lungs- Public Health Agency of Canada estimates that over 3 million Canadians of all

ages are affected by chronic respiratory diseases- Several main causes of respiratory disorders:

Exposure to air pollutants that block parts of the respiratory tract, obstructing airflow or impeding exchange of gases

Exposure to infections pathogens (viruses, bacteria, fungi)

PNEUMONIA- When the alveoli in lungs become inflamed and fill with fluids

PNEUMONIA – disease that causes inflammation in one or both lungs; usually caused by viral infection or bacterial infection

- Interferes with gas exchange, body becomes starved for oxygen- Two main types of pneumonia:

Lobular pneumonia Bronchial pneumonia

- Lobular pneumonia affects a lobe of the lung- Bronchial pneumonia affects patches through both lungs

- Several causes of pneumonia Bacterial infection Viral infection

- Lobular pneumonia caused by the bacterium Streptococcus pneumonia, can spread out of the lungs by way of the bloodstream and can affect other tissues

- Preventative vaccine called pneumococcal vaccine exists that can provide long term protection from the bacterium

- Viral pneumonias usually less severe than bacterial pneumonias, can be treated with anti-viral medications but secondary bacterial infections can follow

- Secondary infection must be treated separately with antibiotics or with preparations that have antibiotic properties

- People with AIDS often experience a rare type of pneumonia that is rare in people with strong immune systems

BRONCHITISBRONCHITIS – respiratory disease that causes inflammation of the mucous membranes of the bronchi, classified as either acute (due to infection) or chronic (due to an irritant); when bronchi become red, inflamed, filled with mucus, which the person expels by coughing

- Short term from of bronchitis called acute bronchitis, usually caused by bacterial infection treatable with antibiotics

- Chronic bronchitis is a long term disorder caused by regular exposure to concentrations of dust or chemical compounds (often in workplaces) or cigarette smoke

- Cilia lining the bronchi gradually destroyed because exposure takes place over a long period of time Without the cleansing action of the cilia, bronchi grow increasingly inflamed and vulnerable to infection

- Mucus accumulates in the bronchi, person develops a persistent cough in an attempt to clear it

- Chronic bronchitis is referred to as a chronic obstructive pulmonary disease (COPD); one of a few lung diseases that is usually caused by smoking

- COPD cannot be cured but can be treated by quitting smoking, taking medications and participating in special exercise programs

ASTHMAASTHMA – lung disease that causes chronic inflammation of the lungs nad overproduction of mucus in the lungs

- Inhaled irritants such as pollen, dust, smoke can trigger an inflammation of the bronchi and bronchioles

- Inflammation narrows air passages of bronchi and bronchioles, reducing airflow

- People with asthma experience wheezing, coughing, tightness in the chest and shortness of breath

- During an asthma attack, muscles around the airways contract and cells in the airways may increase mucus production, blocking airflow even more

- Asthma often starts in childhood, cannot be cured but can be managed; many people use a hand-held inhaler: device that delivers medications deep into the lungs

- Two common types on inhalers Metered dose inhaler: pressurized canister fitted to a mouthpiece;

person fits the mouthpiece, triggers the release and inhales a measured amount of liquid medication into a fine mist to relieve symptoms

Dry powder inhaler: doesn’t use a propellant to push the medication out of the container; person obtains a fine powdered dose of medication using a deep slow inhalation

- Asthma medications act by relaxing the bronchiole muscles and reduce inflammation to open up airways

- People with asthma can monitor their lung capacity to give advance warning of reduced airflow

- Lung capacity can be measured by exhaling into a peak flow meter

EMPHYSEMA- Respiratory disorder in which the walls of the alveoli lose their elasticity

EMPHYSEMA – a chronic respiratory disease that affects the ability of the lungs to expel air

- Loss of elasticity reduces the respiratory surface for gas exchange and causes an oxygen shortage in the tissues

- Exhaling becomes difficult; small airways collapse during exhalation, trapping air in the lungs and blocking airflow

- Most common cause of this condition is smoking- Emphysema is classified as a COPD, incurable but symptoms can be relieved

by using an inhaler to open up the bronchioles and a low-flow oxygen tank to boost the supply of oxygen to the body

- Treatment: stop smoking, avoid airborne irritants (dust, second-hand smoke)

CYSTIC FIBROSISCYSTIC FIBROSIS – genetic disease causing a thick buildup of mucus in the lungs, resulting in infection, inflammation and damage to the lung tissue

- Mutation of a single gene causes a multi-system- Genetic condition that causes cells lining the airways to release thick, sticky

mucus that clogs the lungs, leading to difficulty in breathing- Mucus traps disease-causing agents, making it difficult to clear bacteria

causing lung infections- Mucus also blocks pancreatic ducts, preventing digestive enzymes from

reaching the intestines to digest food- No cure for cystic fibrosis but symptoms can be relieved by medicines that

thin the mucus and antibiotics that reduce bacterial infections- Normal version of the cystic fibrosis gene causes cells to produce a protein

that helps govern the cell’s balance of salt and water- Mutated version of this gene causes the production of a slightly different

protein, which doesn’t function in the same way- Lack of normal protein causes cells to secrete the thick sticky mucus- Gene therapy being explored, treating patients with copies of the normal

gene, first done in 1993- Newer methods: using capsules, sprays, nose drops to deliver the unmutated

gene to cells lining the airways to lungs - Tiny bubbles called liposomes in the sprays and drops contain DNA without

the mutation- Bubbles fuse with outer surfaces of cells that line the airways and DNA passes

through the membranes into the cells- The added DNA instructs the cells to make the correct protein

LUNG CANCER- Disease in which uncontrolled cell growth and division occurs in the lungs- As lung cells continue to grow and divide in an uncontrolled way, they can

create a rapidly growing mass of cells that form a tumour or carcinomaCARCINOMA – a tumour made up of rapidly multiplying cells

- Carcinomas can grow as large as 8cm, significantly reducing the respiratory surface of lungs

- Cancerous cells can also break away from a tumour and travel, spreading cancer to other parts of the lungs and to other organs and tissues

- Spread of cancer from its original site is called metastasis METASTASIS – the spread of cancerous cells from their original site to other parts of the body

- Lung tissues located deep within the thoracic cavity, lung cancer is difficult to detect in its early stages, difficult to treat

- Symptoms: persistent cough, difficulty breathing, chest pain, loss of appetite- Chest X-ray doesn’t show presence of tumours until they are large and

starting to spread- 90% of people die within 5 years of diagnosis, leading cause of cancer deaths

in Canada- Main causes:

Smoking tobacco, tobacco smoke is a carcinogen (cancer causing agent)

Second hand tobacco smoke, other pollutants Radioactive gas radon, found naturally in rocks/soils that can enter

buildings through foundation cracks Asbestos, fibrous heat resistant mineral once commonly used as

insulation in buildings and in break linings

DIAGNOSING RESPIRATORY SYSTEM DISORDERS- Main tool used to detect serious respiratory systems such as lung cancer is a

specialized X-ray technique called computed axial tomographyCOMPUTED AXIAL TOMOGRAPHY – specialized X ray techniques for imaging organs and other tissues in the body, also known as a CAT or CT scan

- CT scans conducted by a CT scanner; person lies in a special bed while a rotating X ray device takes multiple images of the body through 360 degrees

- Images processed by a computer to produce a complete set of cross sectional pictures of the body’s interior, including soft tissue, bone and blood vessels

- Dyes can be use to highlight a particular organ- Technique provides images of parts of the body that cannot be seen on a

standard chest X ray- Allows physicians to make an earlier and more accurate diagnosis of lung

cancer and to plan treatment- From a CT scan, physicians can confirm the presence of a tumour and

measure its size, precise location and relationship to surrounded tissue- About 1000 photographs in one complete rotation

- Spiral CT scanning developed in the mid 1980s- Scanner rotates continuously around the body in a spiral path- Spiral CT scanning produces clear, detailed views of blood vessels and internal

tissues such as those within the chest cavity- Enables doctors to detect lung cancers earlier, while at a more curable stage- Also helpful in severe chest injuries (Ex.. car injuries)- Produces spiral sequences of cross sections through the body that can be

reconstructed using computer software into 3D images of organs and tissues- This additional info increases the chance that even carcinomas as small as 2-

3mm across will be detected

TWO – PHOTON MICROSCOPYTWO-PHOTON MICROSCOPY (TPM) – technique that uses photons to form images of living tissue up to a depth of 1mm, uses special microscopes that emit photons (particles of light) to penetrate samples of biological tissue

- In traditional light microscopy, it isn’t possible to look into solid tissue- In TPM, a fluorescent “marker” added to the tissue sample allows the scientist

to target a particular point in the sample - TPM produces a 3D image of cells in the body without having to extract a

physical sample- Not only gives information about cell structure but reveals how biochemical

processes take place in living cells- TPM used to observe how different drugs applied into the skin are absorbed

and used by tissues- Exploring this technology to locate and analyze rare types of cancerous cells

BRONCHOSCOPY – bronchial endoscopy, technology for viewing, diagnosing and treating the tissues and organs of the respiratory system, uses a special type of endoscope to examine the trachea and lungs to diagnose lung disorders

- While the patient is under general anesthesia, the doctor inserts the bronchoscope through the mouth or nose and into the lungs

- Special attachments to the bronchoscope allows doctors to take mucus and tissue samples for biopsy, remove tumours and repair damaged blood vessels

- Bronchoscopy also frequently used to diagnose asthma

Respiratory Disorder Diagnostic TechnologiesPneumonia - Chest X ray

- Lab tests on blood and sputum (phlegm, mucus)

- Spirometry- Bronchoscopy (severe cases)- Removal of fluid from pleural

membrane (via needle)Chronic bronchitis - Chest X ray to look for lung

damage- Blood gas analysis (measure

oxygen and carbon dioxide in lungs)

- Lab tests in sputum- CT scan- Spirometry- Other lung function tests

Asthma - Stethoscope (listening), physical exam

- Chest X ray

- Lab tests on blood and sputum- Allergy (skin prick) tests- Spirometry- Peak flow meter- Determine over-responsiveness of

airwaysEmphysema - Chest X ray to look for lung

damage- Blood gas analysis (oxygen and

carbon dioxide in lungs)- Lab tests on sputum- Spirometry- Other lung test function tests

Cystic Fibrosis (CF) - Swear test to measure salt content in sweat (high salt content with other symptoms confirms CF)

- Genetic tests (DNA) from cheek swab or blood sample

- Chest X ray to look for inflammation or scarring of lungs

- Sinus x ray to look for sinusitis, complication of CF

- Lung function tests to measure size of lungs, how much air can be inhaled/exhaled, how well lungs deliver oxygen to blood

- Sputum culture to look for Pseudomonas bacteria

Lung Cancer - Chest X ray- CT scan- Lab test on sputum- Blood tests to look for lung cancer

“markers” in the blood- Biopsy of lung tissue by needle

aspiration- Examination and biopsy by

bronchoscopy- Bone scan to rule out metastasis

in bones- Surgical inspection by opening

chest, examining lungs with an endoscope

TECHNOLOGIES FOR TREATING LUNG CANCER- 3 main techniques for treating lung cancer: radiation, chemotherapy, surgery- Killing/removing cancerous cells, choice of treatment depends on type and

extent of cancer, age/health of patient- Radiation therapy uses X rays or other types of radiation to destroy cancer

cells, can be given externally/internally for lung cancer- Most common type of external therapy delivered by high dose radiation from

a machine- Radiation is delivered internally though thin plastic tube inserted into the

lungs during bronchoscopy

- Small amount of radioactive material passed through plastic tube to the cancer site, tube removed after treatment

- Can be used in combination with chemotherapy and after surgery

- Chemotherapy is a treatment in which drugs that destroy cancer cells either taken by mouth or injected into the body

- Chemotherapy used in more advanced stages of cancer- Drugs work by stopping/slowing the growth of cells that are dividing rapidly

such as skin, mouth, digestive tract- Side effects: loss of hair, nausea, mouth sores- Lung surgery involves removing area of lung containing tumours (small part,

lobe, entire lung)- If all cancerous cells are successfully removes, person will be cancer free- If some metastatic cells remain in the body, cancer may begin to spread after

operation

- Laser surgery uses lasers to destroy lug tumours, helps reduce damage to lungs, minimizes scarring, speeds up healing process

- Laser emits high energy beam of light, focuses on a tumour with minimal impact on surrounding tissues

- Energy heats the target cells until they burst- Heat seals blood vessels and reduces blood loss and swelling- 1980s, surgeons modified a YAG (yttrium aluminum garnet) laser to emit a

particular wavelength to use a heat dispersing attachment so the laser can be used in lung surgery

- Can vaporize tumours as small as 1mm in diameter