Acute Respiratory Failure
Acute respiratory failure is a life-threatening condition where your lungs cannot get enough oxygen into your blood or cannot remove enough carbon dioxide from your body. It happens suddenly and requires immediate medical attention.
Table of contents
- What is acute respiratory failure?
- Types of acute respiratory failure
- Signs and symptoms
- What causes acute respiratory failure
- How is it diagnosed?
- Treatment approaches
- Recovery and living with the condition
What is acute respiratory failure?
Acute respiratory failure is a serious condition that develops suddenly, often without much warning, making it difficult to breathe on your own[1]. When you breathe, oxygen enters your lungs and passes into your blood, which carries it to your organs like your heart and brain. At the same time, your body produces carbon dioxide (a waste product) that needs to be removed from your blood and breathed out[3].
In acute respiratory failure, this normal exchange between oxygen and carbon dioxide does not happen properly. Your lungs may not be able to release enough oxygen into your blood, which can prevent your organs from getting what they need to work properly[4]. The condition is defined by acute and progressive low oxygen levels (hypoxemia) developing within hours, days, or up to a month, caused by various breathing, heart, or body-wide diseases in previously healthy patients[5][11].
You can think of respiration as passengers traveling from the air to your tissues. When you breathe in, oxygen molecules travel to your lungs and arrive at small air sacs called alveoli, where they are picked up by your blood. They travel through your blood to organs and muscles. After dropping off oxygen, your blood picks up carbon dioxide and carries it back to your lungs, where you breathe it out to make room for more oxygen. If any parts of this system fail, you will not have enough oxygen to keep your tissues healthy[1].
Types of acute respiratory failure
There are two main types of acute respiratory failure based on what goes wrong with your breathing: hypoxemic respiratory failure and hypercapnic respiratory failure. Both types can be serious, and they often occur together[6].
Hypoxemic respiratory failure, also called type 1 or hypoxic respiratory failure, happens when there is not enough oxygen in your blood. This can result from swelling of the lungs or fluid buildup that prevents oxygen from passing properly into your blood[4]. Heart and lung conditions are the most common causes. A person experiencing this condition will still have stable carbon dioxide levels in their blood[1].
Hypercapnic respiratory failure, also called type 2 or hypercarbic respiratory failure, occurs when you have too much carbon dioxide in your blood. This happens when the air sacs in your lungs cannot adequately get rid of the carbon dioxide your body produces[4]. If your body cannot remove carbon dioxide, there is not enough room in your blood to carry oxygen. Blood oxygen levels may remain steady or be lower than usual[1].
Other types include perioperative respiratory failure (type 3), which can happen during or after surgery when anesthesia keeps you from breathing properly or when air sacs in your lungs collapse[1]. Respiratory failure due to shock (type 4) can develop when conditions like sepsis, heart attack, or blood loss cause low blood pressure and fluid in the lungs[1].
Signs and symptoms
The symptoms of acute respiratory failure depend on the underlying cause and the levels of oxygen and carbon dioxide in your blood. Because this condition develops suddenly and is life-threatening, recognizing the warning signs is crucial[1].
Common symptoms include shortness of breath or feeling like you cannot get enough air, rapid breathing, and extreme tiredness. You may also experience a fast heart rate, feeling like your heart is racing[1][3].
A low oxygen level in the blood can cause a bluish color on your skin, lips, and fingernails. You may also feel confused, very sleepy, or even faint. Some people lose consciousness or develop an irregular heartbeat[3][6]. These symptoms occur when your brain and heart are not getting enough oxygen[3].
A high carbon dioxide level can cause rapid breathing and confusion. Excessive sleepiness is also a warning sign[1][4].
If you suddenly experience trouble breathing, feel confused, or if family or caregivers notice a bluish color on your skin or lips, call emergency services immediately. Acute respiratory failure requires emergency treatment[3].
What causes acute respiratory failure
Acute respiratory failure usually occurs when there is difficulty getting enough oxygen to the lungs, problems removing carbon dioxide from the lungs, or both. This can happen due to tissue damage, fluid buildup, muscle spasms, or other physical problems[4].
Many different conditions can cause acute respiratory failure. These include lung diseases such as pneumonia (infection of the lungs), chronic obstructive pulmonary disease or COPD, pulmonary embolism (blood clot in the lungs), and cystic fibrosis[1][4].
Conditions affecting the nerves and muscles that control breathing can also lead to respiratory failure. These include amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease), muscular dystrophy, stroke, and spinal cord injuries[4].
Problems with the spine, such as scoliosis (a curve in the spine), can affect the bones and muscles used for breathing[4]. Damage to the tissues and ribs around the lungs from a chest injury can also cause respiratory failure.
Other causes include drug or alcohol overdose, inhalation injuries such as inhaling smoke from fires or harmful fumes, and infections like COVID-19[3][4].
How is it diagnosed?
Your healthcare provider will diagnose acute respiratory failure based on your medical history, a physical exam, and diagnostic tests[3].
During the physical exam, your doctor will listen to your lungs to check for abnormal sounds and listen to your heart to check for irregular heartbeat. They will also look for a bluish color on your skin, lips, and fingernails[3].
Diagnostic tests are essential to confirm the diagnosis and measure how severe the condition is. Pulse oximetry uses a small sensor, usually placed on the end of your finger or on your ear, that uses light to measure how much oxygen is in your blood[3].
An arterial blood gas test measures the oxygen and carbon dioxide levels in your blood. The blood sample is taken from an artery, usually in your wrist. This test helps determine the type and severity of respiratory failure[3].
Once respiratory failure is diagnosed, your provider will look for what is causing it. A chest X-ray is often done to examine the lungs. If your provider thinks you may have an irregular heartbeat because of respiratory failure, you may have an electrocardiogram or EKG, a simple, painless test that detects and records your heart’s electrical activity[3].
Other tests may include lung function tests to check how well your lungs are working, including spirometry, which measures how much air you can breathe in and out[7].
Treatment approaches
Acute respiratory failure can be life-threatening and often requires emergency treatment in a hospital, typically in an intensive care unit[3][9]. Emergency treatment helps quickly improve your breathing and provides oxygen to your body to help prevent organ damage. Your healthcare provider will then treat the underlying cause of respiratory failure[9].
The first goal of treatment is to increase oxygen levels in the blood so that organs function better. One of the main treatments is oxygen therapy, which delivers oxygen through different methods[9].
For milder symptoms, oxygen may be delivered through a mask that fits over your nose and mouth, or through plastic tubes placed in your nose[9][13].
Noninvasive positive pressure ventilation or NPPV uses mild air pressure to keep your airways open. You wear a mask or another device that fits over your nose or your nose and mouth. A tube connects the mask to a machine that blows air into the tube. This method is now weakly recommended for initial management of certain conditions[5][9].
High-flow nasal cannula oxygenation is increasingly used as an alternative treatment. It delivers a high flow of humidified warm oxygen through a special nasal tube. This treatment is now weakly recommended for respiratory management in general[5][14].
Most people with acute respiratory failure need the help of a mechanical ventilator, a machine that supports breathing. It blows air, or air with increased amounts of oxygen, into your airways and then your lungs. Your healthcare provider may use a ventilator if the oxygen level in your blood does not increase with other treatments, or if you are still having trouble breathing[9]. The machine connects to your body through a tube placed in your windpipe.
In severe cases, extracorporeal membrane oxygenation or ECMO may be used. This process removes blood from your body and oxygenates it externally before returning it. ECMO functions as an artificial lung working in addition to your failing lungs[9][20].
Other treatments may include medicines delivered through an inhaler or nebulizer machine to open up airways, allowing your lungs to pick up oxygen more effectively[13]. Fluids may be given through an intravenous line to ensure you have the right amount in your body, supporting proper blood flow without causing fluid to build up in the lungs[13].
Recovery and living with the condition
Recovery from acute respiratory failure can take many weeks or months, particularly for older adults. The longer you were on a ventilator, the longer it may take to recover your strength and return to familiar routines[15][23].
As you recover, your oxygen and carbon dioxide levels may take time to return to a healthy range. You may continue to have shortness of breath or other symptoms for a few weeks or longer. You may need to do daily activities more slowly[15].
It is important to follow your treatment plan and get regular follow-up care. Keep regular appointments so your doctor can monitor your recovery. Take all medicines regularly as prescribed, and do not change the amount of your medicine or oxygen or skip a dose unless your doctor tells you to[15][23].
Your doctor may recommend working with therapists or other healthcare providers to gain strength and speed your recovery. Pulmonary rehabilitation is an exercise training, education, and counseling program that can help your lungs work better[15][18].
Many survivors experience physical and psychological challenges after hospitalization. Common issues include muscle weakness from being in bed for a long time, and psychological problems such as anxiety and depression[17][18].
Watch for warning signs if you had to use a mechanical ventilator, as using one for a long time may hurt your lungs and windpipe. Between visits, call your doctor if you have any new symptoms or if your symptoms suddenly get worse. Call emergency services for help if you suddenly have trouble breathing or talking[15].
If you continue to need oxygen at home, you may have to carry a portable oxygen tank and a tube that goes into your nose. Your healthcare team can support your recovery and suggest additional resources. Talk to your doctor about when you can resume normal activities[15].
