Respiratory (RES-pih-rah-tor-e) failure is a condition in which not enough oxygen passes from your lungs into your blood. Your body's organs, such as your heart and brain, need oxygen-rich blood to work well. Respiratory failure also can occur if your lungs can't properly remove carbon dioxide (a waste gas) from your blood. Too much carbon dioxide in your blood can harm your body's organs. Both of these problems—a low oxygen level and a high carbon dioxide level in the blood—can occur at the same time. Diseases and conditions that affect your breathing can cause respiratory failure. Examples include COPD (chronic obstructive pulmonary disease) and spinal cord injuries. COPD prevents enough air from flowing in and out of the airways. Spinal cord injuries can damage the nerves that control breathing.
To understand respiratory failure, it helps to understand how the lungs work. When you breathe, air passes through your nose and mouth into your windpipe. The air then travels to your lungs' air sacs. These sacs are called alveoli (al-VEE-uhl-eye). Small blood vessels called capillaries run through the walls of the air sacs. When air reaches the air sacs, the oxygen in the air passes through the air sac walls into the blood in the capillaries. At the same time, carbon dioxide moves from the capillaries into the air sacs. This process is called gas exchange.
In respiratory failure, gas exchange is impaired. Respiratory failure can be acute (short term) or chronic (ongoing). Acute respiratory failure can develop quickly and may require emergency treatment. Chronic respiratory failure develops more slowly and lasts longer.
Signs and symptoms of respiratory failure may include shortness of breath, rapid breathing, and air hunger (feeling like you can't breathe in enough air). In severe cases, signs and symptoms may include a bluish color on your skin, lips, and fingernails; confusion; and sleepiness.
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.
Acute respiratory failure usually is treated in an intensive care unit. Chronic respiratory failure can be treated at home or at a long-term care center.
The outlook for respiratory failure depends on the severity of its underlying cause, how quickly treatment begins, and your overall health.
People who have severe lung diseases may need long-term or ongoing breathing support, such as oxygen therapy or the help of a ventilator (VEN-til-a-tor). 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.
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:
Normal Lungs and Conditions Causing 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?"
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.
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.
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.
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.
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.
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.
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 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.
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.
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.
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.
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.
Your doctor may prescribe medicines to relieve discomfort.
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.