Respiratory system diseases

Types of pulmonary diseases

Learn what the main classifications of lung diseases are: obstructive, restrictive, ventilation, and perfusion. Discover the classification of common diseases like asthma, emphysema, and pneumonia.

Respiratory distress

How can you tell someone is having troubles breathing? Increased work of breathing, the feeling of shortness of breath, and cyanosis are all common symptoms of respiratory distress. Learn what these symptoms look like and why they occur.

Streptococcus pneumoniae and flu vaccines

Why do we need a new flu vaccine every year? Learn about the pneumonia and flu vaccines and how they help your body fight off infection.

What is the flu?

Learn the difference between the cold and the flu, and how we sometimes can get fooled by viruses! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Catching and spreading the flu

Find out how the flu spreads from person to person, and who is at the greatest risk of getting complications of the flu. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

When flu viruses attack!

Learn how flu viruses get into and out of your cells using Hemagglutinin and Neuraminidase proteins on their surface. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Three types of flu

Learn about the three types of influenza virus (Type A, Type B, and Type C) and what makes them differ from one another. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Naming the flu: H-something, N-something

We've all heard of H1N1 or H3N2; now you can understand what all of those names mean and find out why they are helpful in keeping track of the different flu virueses! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Testing for the flu

Learn when testing for influenza makes sense, and the most common test that is used. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Antiviral drugs for the flu

Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Genetic shift in flu

Find out how the genetic material in the Type A flu virus can get shuffled around to create brand new types of viruses! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Flu vaccine efficacy

Find out just how useful the flu vaccine actually is at preventing the flu! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Flu shift and drift

Learn how Type B Influenza virus has genetic drift, whereas Type A Influenza virus has genetic drift AND shift. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Two flu vaccines (TIV and LAIV)

Understand the differences between TIV (dead virus) and LAIV (alive, but weakened virus) and who should get which one. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Flu vaccine risks and benefits

Learn about some of the common and uncommon risks and benefits associated with the flu vaccine! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Making flu vaccine each year

Learn about how the flu vaccine is made every year and how they name the strains that they put inside. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

5 common flu vaccine excuses

Many people choose to avoid the flu vaccine each year. Review five popular excuses, and how they relate to common misunderstandings about the flu. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Vaccines and the autism myth - part 1

The infamous Wakefield study kickstarted the Autism Myth, but many studies have since shown that there is no link between the MMR Vaccine and autism. Find out how it all got started. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Vaccines and the autism myth - part 2

The infamous Wakefield study kickstarted the Autism Myth, but many studies have since shown that there is no link between the MMR Vaccine and autism. Find out how it all got started. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Flu surveillance

Find out how many people get hospitalized and die from the flu each year, and learn how we can use the internet to keep tabs on the flu! Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

What is TB?

Find out the basics of TB, where it comes from and where it goes. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

TB epidemiology

Find out how many lives are affected by TB around the world. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

TB pathogenesis

Find out exactly how TB causes damage to the lungs. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Primary and Secondary TB

Learn some key features of primary TB and how it differs from secondary TB. Rishi is a pediatric infectious disease physician and works at Khan Academy.These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Pulmonary TB

Learn the effects that TB has on the lungs and some important clinical clues. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Extrapulmonary TB (part 1)

Learn about how TB can spread beyond your lungs. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Extrapulmonary TB (Part 2)

Learn about how TB can spread beyond your lungs. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Mantoux test (aka. PPD or TST)

Learn how the Mantoux test is done and how it works. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Interpreting the PPD

Find out how the cutoff for a "positive PPD" depends on clinical clues. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Diagnosing active TB

Find out how we can use clinical clues to help figure out if someone has active TB infection. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Preventing TB transmission

There are a number of ways that we can help to prevent TB from spreading, learn some of the most common ones. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Preventing TB using the "4 I's"

Learn how to help prevent TB disease using Intensive case finding, Isoniazid, Isolation, and Immunization. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Treatment of Active TB

Learn which medications help prevent active TB disease. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

Drug-resistant TB

Learn the different types of drug-resistant TB These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

TB and HIV

Two deadly diseases, HIV and TB, can often co-exist in the same patient. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

What is emphysema?

Emphysema is a chronic medical condition (most often caused by smoking and air pollution) where lung tissue is damaged and traps air inside the lung. Learn how shortness of breath, persistent cough, and wheezing are common symptoms of this condition and why they occur in emphysema.

Emphysema pathophysiology

Smoking and air pollution cause the alveoli in the lungs stiff and less stretchy, making it difficult for air to escape during exhalation. Learn how the destruction of the protein elastin is key to the progression of emphysema, and how the over production of elastase occurs.

Emphysema diagnosis

How do we know a patient has emphysema? Learn how the lungs in chest x-rays look hyperinflated, how spirometry can reveal decreased lung function, and what all those blood tests mean.

Diffusing capacity of the lung for carbon monoxide (DLCO)

Diffusing capacity of the lungs for carbon monoxide (DLCO) is a medical test that determines how much oxygen travels from the alveoli of the lungs to the blood stream. Learn what DLCO is, how DLCO a good measure of lung disease severity, and why we use carbon monoxide instead of oxygen or carbon dioxide.

Centriacinar emphysema vs panacinar emphysema

Centriacinar and panacinar are different classifications of disease emphysema based on the location of the damaged lung tissue. Learn how inflammation can give rise to centriacinar emphysema, and how a deficiency in alpha-1-antitrypsin can lead to panacinar emphysema.

Emphysema treatment

The best way to prevent and manage emphysema is to stop smoking. Learn how drugs such as bronchodilators, antibiotics, and steroids can be used to manage the symptoms of emphysema.

What is lung cancer?

Lung cancer is a disease where cells in the lungs multiply uncontrollably. The extra cells take up space in the lungs and impair gas exchange and the lung’s ability to expel dirt. Learn how smoking, radon gas, and air pollution increase the risk of lung cancer.

Lung cancer diagnosis

How do we know a patient has lung cancer? Learn how health professionals use x-rays, computed tomography (CT scans), positron emission tomography (PET scans), and blood results to confirm lung cancer in patients.

Lung cancer types

There are several different types of lung cancer, such as small cell lung cancer, non-small cell lung cancer, adenocarcinoma, squamous cell carcinoma, large cell carcinoma, and carcinoid . Learn how each type of lung cancer occurs, and how common they are amongst other lung cancers.

Lung cancer complications

Learn how the mass of a tumor, the spread of cancer cells, the immune system’s response, and the hormones released from cancer cells contribute to the complications of lung cancer.

Lung cancer metastasis

Metastasis is the spread of cancer cells from one area of the body (such as an organ) to another. As cancerous cells multiply, some cells may find their way into the circulating blood or lymphatic systems, where they’re transported around the rest of the body. They may eventually land in another organ where they continue to multiply and spread.

Lung cancer staging

Health professionals use special terminology referred to as stages to concisely communicate the progression of cancer disease. Learn how cancer is classified based off the size of the tumor, the involvement of lymph nodes, and whether metastasis has occurred.

Lung cancer treatment

Lung cancer is treated using a combination of treatments such as chemotherapy, radiation, and a variety of surgical procedures (such as wedge resections, pneumonectomies, and segmental resections). Learn about the complications and side effects of treatment options and why they occur.

What is pneumonia?

Pneumonia is a medical condition where lung tissue becomes inflamed, usually caused by a virus or bacteria. Learn how shortness of breath, cough, and fever are common symptoms of this condition and why they occur in pneumonia.

Streptococcus pneumoniae and flu vaccines

Why do we need a new flu vaccine every year? Learn about the pneumonia and flu vaccines and how they help your body fight off infection.

Pulmonary abscess

Pulmonary abscesses occur when part of the lung tissue dies (caused by damage or infection) and gets trapped in a layer of hard tissue in the lung. Learn what causes abscesses, how they are diagnosed, and how health professionals treat them.

Pneumonia vs. pneumonitis

Pneumonitis is a term used to describe inflammation of the lung tissues without the presence of an infection, whereas pneumonia is inflammation caused by an infection. Learn what the symptoms of pneumonitis are, and why pneumonitis is more common with bird handlers, farmers, and people who regularly use humidifiers.

What is a pleural effusion?

Pleural effusions are when excess fluid get caught between two layers of tissue (the visceral and parietal pleurae) surrounding the lungs. This fluid can build up over time, taking up space in the lung and impairing a person’s ability to breath. Learn about the signs and symptoms of pleural effusions such as chest pain, shortness of breath, and dry coughing.

Pleural effusion diagnosis and treatment

How do we know a patient has a pleural effusion? Health professionals use x-rays, and computed tomography (CT scans) to look for extra fluid inside the body. Learn how pleural effusions are treated using techniques such as a thoracentesis, pleurodesis, and pleuroperitoneal shunts.

Transudate vs exudate

In a pleural effusion, different fluids can enter the pleural cavity. Transudate is fluid pushed through the capillary due to high pressure within the capillary. Exudate is fluid that leaks around the cells of the capillaries caused by inflammation. Learn why transudative fluid does not contain proteins, why exudate does contain proteins, and how health professionals can differentiate between the two using Light’s criteria.

Neurovascular bundle

The neurovascular bundles located underneath the ribs are small collections of blood vessels (veins and arteries) and nerves which supply the tissues of the chest wall. When procedures such as a thoracentesis are performed, health professionals must avoid hitting this bundle. If they do, the patient may have significant bleeding, hypotension, shock, and decreased respiratory function.