What is acute respiratory failure?

Acute respiratory failure occurs when fluid builds up in the air sacs in your lungs. When that happens, your lungs can’t release oxygen into your blood. In turn, your organs can’t get enough oxygen-rich blood to function. You can also develop acute respiratory failure if your lungs can’t remove carbon dioxide from your blood.

Respiratory failure happens when the capillaries, or tiny blood vessels, surrounding your air sacs can’t properly exchange carbon dioxide for oxygen. The condition can be acute or chronic. With acute respiratory failure, you experience immediate symptoms from not having enough oxygen in your body. In most cases, this failure may lead to death if it’s not treated quickly.

The two types of acute and chronic respiratory failure are hypoxemic and hypercapnic. Both conditions can trigger serious complications and the conditions often coexist.

Hypoxemic respiratory failure means that you don’t have enough oxygen in your blood, but your levels of carbon dioxide are close to normal.

Hypercapnic respiratory failure means that there’s too much carbon dioxide in your blood, and near normal or not enough oxygen in your blood.

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

People with a high carbon dioxide level may experience:

People with low oxygen levels may experience:

People with acute failure of the lungs and low oxygen levels may experience:

Acute respiratory failure has several different causes:


When something lodges in your throat, you may have trouble getting enough oxygen into your lungs. Obstruction can also occur in people with chronic obstructive pulmonary disease (COPD) or asthma when an exacerbation causes the airways to become narrow.


An injury that impairs or compromises your respiratory system can adversely affect the amount of oxygen in your blood. For instance, an injury to the spinal cord or brain can immediately affect your breathing. The brain tells the lungs to breathe. If the brain can’t relay messages due to injury or damage, the lungs can’t continue to function properly.

An injury to the ribs or chest can also hamper the breathing process. These injuries can impair your ability to inhale enough oxygen into your lungs.

Acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a serious condition characterized by low oxygen in the blood. ARDS affects you if you already have an underlying health problem such as:

It can occur while you’re in the hospital being treated for your underlying condition.

Drug or alcohol abuse

If you overdose on drugs or drink too much alcohol, you can impair brain function and hinder your ability to breathe in or exhale.

Chemical inhalation

Inhaling toxic chemicals, smoke, or fumes can also cause acute respiratory failure. These chemicals may injure or damage the tissues of your lungs, including the air sacs and capillaries.


A stroke occurs when your brain experiences tissue death or damage on one or both sides of the brain. Often, it affects only one side. Although stroke does present some warning signs, such as slurred speech or confusion, it typically occurs quickly. If you have a stroke, you may lose your ability to breathe properly.


Infections are a common cause of respiratory distress. Pneumonia in particular, may cause respiratory failure, even in the absence of ARDS. According to the Mayo Clinic, in some cases pneumonia affects all five lobes of the lungs.

You may be at risk for acute respiratory failure if you:

  • smoke tobacco products
  • drink alcohol excessively
  • have a family history of respiratory disease or conditions
  • sustain an injury to the spine, brain, or chest
  • have a compromised immune system
  • have chronic (long-term) respiratory problems, such as cancer of the lungs, chronic obstructive pulmonary disease (COPD), or asthma

Acute respiratory failure requires immediate medical attention. You may receive oxygen to help you breathe and to prevent tissue death in your organs and brain.

After your doctor stabilizes you, he or she will take certain steps to diagnose your condition, such as:

  • perform a physical exam
  • ask you questions about your family or personal health history
  • check your body’s oxygen and carbon dioxide levels level with a pulse oximetry device and an arterial blood gas test
  • order a chest X-ray to look for abnormalities in your lungs

Treatment usually addresses any underlying conditions you may have. Your doctor will then treat your respiratory failure with a variety of options.

  • Your doctor may prescribe pain medications or other medicines to help you breathe better.
  • If you can breathe adequately on your own and your hypoxemia is mild, you may receive oxygen from an oxygen tank to help you breathe better. Portable air tanks are available if your condition requires one.
  • If you can’t breathe adequately on your own, your doctor may insert a breathing tube into your mouth or nose, and connect the tube to a ventilator to help you breathe.
  • If you require prolonged ventilator support, an operation that creates an artificial airway in the windpipe called a tracheostomy may be necessary.
  • You may receive oxygen via an oxygen tank or ventilator to help you breathe better.

You may see improvement in your lung function if you get appropriate treatment for your underlying condition. You may also require pulmonary rehabilitation, which includes exercise therapy, education, and counseling.

Acute respiratory failure can cause long-term damage to your lungs. It’s important to seek emergency medical care if you’re experiencing the symptoms of respiratory failure.