For more information, visit http://www.nhlbi.nih.gov/health/health-topics/topics/rf/

Other Names for Respiratory Failure

• When respiratory failure causes a low level of oxygen in the blood, it's called hypoxemic (HI-pok-SE-mik) respiratory failure.
• When respiratory failure causes a high level of carbon dioxide in the blood, it's called hypercapnic (HI-per-KAP-nik) respiratory failure.

What Causes Respiratory Failure?

Diseases and conditions that impair breathing can cause respiratory failure. These disorders may affect the muscles, nerves, bones, or tissues that support breathing, or they may affect the lungs directly.

When breathing is impaired, your lungs can't easily move oxygen into your blood and remove carbon dioxide from your blood (gas exchange). This can cause a low oxygen level or high carbon dioxide level, or both, in your blood.

Respiratory failure can occur as a result of:

• Conditions that affect the nerves and muscles that control breathing. Examples include muscular dystrophy, amyotrophic lateral sclerosis (ALS), spinal cord injuries, and stroke.
• Damage to the tissues and ribs around the lungs. An injury to the chest can cause this damage.
• Problems with the spine, such as scoliosis (a curve in the spine). This condition can affect the bones and muscles used for breathing.
• Drug or alcohol overdose. An overdose affects the area of the brain that controls breathing. During an overdose, breathing becomes slow and shallow.
• Lung diseases and conditions, such as COPD (chronic obstructive pulmonary disease), pneumonia, ARDS (acute respiratory distress syndrome), pulmonary embolism, and cystic fibrosis. These diseases and conditions can affect the flow of air and blood into and out of your lungs. ARDS and pneumonia affect gas exchange in the air sacs.
• Acute lung injuries. For example, inhaling harmful fumes or smoke can injure your lungs.

Normal Lungs and Conditions Causing Respiratory Failure

Figure A shows the location of the lungs, airways, diaphragm, rib cage, pulmonary arteries, brain, and spinal cord in the body. Figure B shows the major conditions that cause respiratory failure.

Who Is at Risk for Respiratory Failure?

People who have diseases or conditions that affect the muscles, nerves, bones, or tissues that support breathing are at risk for respiratory failure. People who have lung diseases or conditions also are at risk for respiratory failure. For more information, go to "What Causes Respiratory Failure?"

What Are the Signs and Symptoms of Respiratory Failure?

The signs and symptoms of respiratory failure depend on its underlying cause and the levels of oxygen and carbon dioxide in the blood.

A low oxygen level in the blood can cause shortness of breath and air hunger (feeling like you can't breathe in enough air). If the level of oxygen is very low, it also can cause a bluish color on the skin, lips, and fingernails. A high carbon dioxide level can cause rapid breathing and confusion.

Some people who have respiratory failure may become very sleepy or lose consciousness. They also may develop arrhythmias (ah-RITH-me-ahs), or irregular heartbeats. These symptoms can occur if the brain and heart are not getting enough oxygen.

How Is Respiratory Failure Diagnosed?

Your doctor will diagnose respiratory failure based on your medical history, a physical exam, and test results. Once respiratory failure is diagnosed, your doctor will look for its underlying cause.

Medical History

Your doctor will ask whether you might have or have recently had diseases or conditions that could lead to respiratory failure. 

Examples include disorders that affect the muscles, nerves, bones, or tissues that support breathing. Lung diseases and conditions also can cause respiratory failure.

For more information, go to "What Causes Respiratory Failure?"

Physical Exam

During the physical exam, your doctor will look for signs of respiratory failure and its underlying cause.

Respiratory failure can cause shortness of breath, rapid breathing, and air hunger (feeling like you can't breathe in enough air). Using a stethoscope, your doctor can listen to your lungs for abnormal sounds, such as crackling.

Your doctor also may listen to your heart for signs of an arrhythmia (irregular heartbeat). An arrhythmia can occur if your heart doesn't get enough oxygen.

Your doctor might look for a bluish color on your skin, lips, and fingernails. A bluish color means your blood has a low oxygen level.

Respiratory failure also can cause extreme sleepiness and confusion, so your doctor might check how alert you are.

Diagnostic Tests

To check the oxygen and carbon dioxide levels in your blood, you may have:  

• Pulse oximetry. For this test, a small sensor is attached to your finger or ear. The sensor uses light to estimate how much oxygen is in your blood.
• Arterial blood gas test. This test measures the oxygen and carbon dioxide levels in your blood. A blood sample is taken from an artery, usually in your wrist. The sample is then sent to a laboratory, where its oxygen and carbon dioxide levels are measured.

A low level of oxygen or a high level of carbon dioxide in the blood (or both) is a possible sign of respiratory failure.

Your doctor may recommend other tests, such as a chest x ray, to help find the underlying cause of respiratory failure. A chest x ray is a painless test that takes pictures of the structures inside your chest, such as your heart, lungs, and blood vessels.

If your doctor thinks that you have an arrhythmia as a result of respiratory failure, he or she may recommend an EKG (electrocardiogram). An EKG is a simple, painless test that detects and records the heart's electrical activity.

How Is Respiratory Failure Treated?

Treatment for respiratory failure depends on whether the condition is acute (short-term) or chronic (ongoing) and its severity. Treatment also depends on the condition's underlying cause.

Acute respiratory failure can be a medical emergency. It often is treated in an intensive care unit at a hospital. Chronic respiratory failure often can be treated at home. If chronic respiratory failure is severe, your doctor may recommend treatment in a long-term care center.

One of the main goals of treating respiratory failure is to get oxygen to your lungs and other organs and remove carbon dioxide from your body. Another goal is to treat the underlying cause of the condition.

Oxygen Therapy and Ventilator Support

If you have respiratory failure, you may receive oxygen therapy. Extra oxygen is given through a nasal cannula (two small plastic tubes, or prongs, that are placed in both nostrils) or through a mask that fits over your nose and mouth.

Oxygen Therapy

The image shows how a nasal cannula and portable oxygen container are attached to a patient.

Oxygen also can be given through a tracheostomy (TRA-ke-OS-to-me). This is a surgically made hole that goes through the front of your neck and into your windpipe. A breathing tube, also called a tracheostomy or trach tube, is placed in the hole to help you breathe.

Tracheostomy

Figure A shows a side view of the neck and the correct placement of a tracheostomy tube in the trachea, or windpipe. Figure B shows an external view of a patient who has a tracheostomy.

If the oxygen level in your blood doesn't increase, or if you're still having trouble breathing, your doctor may recommend a ventilator. A ventilator is a machine that supports breathing. It blows air—or air with increased amounts of oxygen—into your airways and then your lungs.

Ventilator

The illustration shows a standard setup for a ventilator in a hospital room. The ventilator pushes warm, moist air (or air with increased oxygen) to the patient. Exhaled air flows away from the patient.

Your doctor will adjust the ventilator as needed. This will help your lungs get the right amount of oxygen. It also can prevent the machine's pressure from injuring your lungs. You'll use the ventilator until you can breathe on your own.

Other Treatments To Help You Breathe

Noninvasive positive pressure ventilation (NPPV) and a rocking bed are two methods that can help you breathe better while you sleep. These methods are very useful for people who have chronic respiratory failure.

NPPV is a treatment that uses mild air pressure to keep your airways open while you sleep. You wear a mask or other device that fits over your nose or your nose and mouth. A tube connects the mask to a machine, which blows air into the tube.

CPAP (continuous positive airway pressure) is one type of NPPV. For more information, go to the Health Topics CPAP article. Although the article focuses on CPAP treatment for sleep apnea, it explains how CPAP works.

A rocking bed consists of a mattress on a motorized platform. The mattress gently rocks back and forth. When your head rocks down, the organs in your abdomen and your diaphragm (the main muscle used for breathing) slide up, helping you exhale. When your head rocks up, the organs in your abdomen and your diaphragm slide down, helping you inhale.

Fluids

You may be given fluids to improve blood flow throughout your body and to provide nutrition. Your doctor will make sure you get the right amount of fluids.

Too much fluid can fill the lungs and make it hard for you to get the oxygen you need. Not enough fluid can limit the flow of oxygen-rich blood to the body's organs.

Fluids usually are given through an intravenous (IV) line inserted in one of your blood vessels.

Medicines

Your doctor may prescribe medicines to relieve discomfort.

Treatments for the Underlying Cause of Respiratory Failure

Once your doctor figures out what's causing your respiratory failure, he or she will plan how to treat that disease or condition. Treatments may include medicines, procedures, and other therapies.

Living With Respiratory Failure

One of the main goals of treating respiratory failure is to treat the underlying cause of the condition. However, sometimes it's hard to cure or control the underlying cause. Thus, respiratory failure may last for weeks or even years. This is called chronic respiratory failure.

Oxygen therapy and other treatments can help you breathe easier. However, your oxygen and carbon dioxide levels still may not be normal. Thus, you may have one or more of the following symptoms:

• Shortness of breath
• Rapid breathing
• Tiredness and confusion

These symptoms may go away within a few weeks or last longer. Talk with your doctor about how to deal with these symptoms, and read the tips below.

Ongoing Care

If you have respiratory failure, see your doctor for ongoing medical care. Your doctor may refer you to pulmonary rehabilitation (rehab).

Rehab can involve exercise training, education, and counseling. Your rehab team might include doctors, nurses, and other specialists. They'll work with you to create a program that meets your needs.

If you smoke, quit. Talk to your doctor about programs and products that can help you quit smoking. Also, try to avoid secondhand smoke.

If you have trouble quitting smoking on your own, consider joining a support group. Many hospitals, workplaces, and community groups offer classes to help people quit smoking.

If you're on oxygen therapy, don't smoke. Oxygen isn't explosive, but it can worsen a fire. In the presence of oxygen, a small fire can quickly get out of control. Also, the cylinder that compressed oxygen gas comes in can explode when exposed to heat.

For more information about how to quit smoking, go to the Health Topics Smoking and Your Heart article. Although this resource focuses on heart health, it includes basic information about how to quit smoking.

Emotional Issues and Support

Living with respiratory failure may cause fear, anxiety, depression, and stress. Talk about how you feel with your health care team. Talking to a professional counselor also can help. If you're very depressed, your doctor may recommend medicines or other treatments that can improve your quality of life.

Joining a patient support group may help you adjust to living with respiratory failure. You can see how other people who have the same symptoms have coped with them. Talk to your doctor about local support groups or check with an area medical center.

Support from family and friends also can help relieve stress and anxiety. Let your loved ones know how you feel and what they can do to help you.

Prepare for Emergencies

If you have chronic respiratory failure, knowing when and where to seek help for your symptoms is important. You should seek emergency care if you have severe symptoms, such as trouble catching your breath or talking.

Call your doctor if you notice that your symptoms are worsening or if you have new signs and symptoms. Your doctor may change or adjust your treatments to relieve and treat symptoms.

Keep phone numbers handy for your doctor, hospital, and someone who can take you for medical care. You also should have on hand directions to the doctor's office and hospital and a list of all the medicines you're taking.

Clinical Trials

The National Heart, Lung, and Blood Institute (NHLBI) is strongly committed to supporting research aimed at preventing and treating heart, lung, and blood diseases and conditions and sleep disorders.

NHLBI-supported research has led to many advances in medical knowledge and care. Often, these advances depend on the willingness of volunteers to take part in clinical trials.

Clinical trials test new ways to prevent, diagnose, or treat various diseases and conditions. For example, new treatments for a disease or condition (such as medicines, medical devices, surgeries, or procedures) are tested in volunteers who have the illness. Testing shows whether a treatment is safe and effective in humans before it is made available for widespread use.

By taking part in a clinical trial, you can gain access to new treatments before they're widely available. You also will have the support of a team of health care providers, who will likely monitor your health closely. Even if you don't directly benefit from the results of a clinical trial, the information gathered can help others and add to scientific knowledge.

If you volunteer for a clinical trial, the research will be explained to you in detail. You'll learn about treatments and tests you may receive, and the benefits and risks they may pose. You'll also be given a chance to ask questions about the research. This process is called informed consent.

If you agree to take part in the trial, you'll be asked to sign an informed consent form. This form is not a contract. You have the right to withdraw from a study at any time, for any reason. Also, you have the right to learn about new risks or findings that emerge during the trial.

For more information about clinical trials related to respiratory failure, talk with your doctor. You also can visit the following Web sites to learn more about clinical research and to search for clinical trials:

• http://clinicalresearch.nih.gov
• www.clinicaltrials.gov
• www.nhlbi.nih.gov/studies/index.htm
• www.researchmatch.org

For more information about clinical trials for children, visit the NHLBI's Children and Clinical Studies Web page.

Links to Other Information About Respiratory Failure

NHLBI Resources

• ARDS (Health Topics)
• COPD (Health Topics)
• CPAP (Health Topics)
• Cystic Fibrosis (Health Topics)
• How the Lungs Work (Health Topics)
• Oxygen Therapy (Health Topics)
• Pneumonia (Health Topics)
• Pulmonary Embolism (Health Topics)
• Pulmonary Rehabilitation (Health Topics)
• Ventilator/Ventilator Support (Health Topics)

Non-NHLBI Resources

• Respiratory Acidosis (MedlinePlus)
• Respiratory Failure (MedlinePlus)

Clinical Trials

• Children and Clinical Studies
• Clinical Trials (Health Topics)
• Current Research (ClinicalTrials.gov)
• NHLBI Clinical Trials
• NIH Clinical Research Trials and You (National Institutes of Health)
• ResearchMatch (funded by the National Institutes of Health)