Acute respiratory distress syndrome (ARDS)

Recommend to others!


ARDS or acute respiratory distress syndrome is a lung condition characterized by low levels of oxygen in the blood. This may endanger a person’s life.

The condition is caused by the fact that body organs such as the kidneys and brain, need oxygen-rich blood to function properly.

ARDS usually occurs in people who are very ill, suffering from severe diseases or have other major injuries. Most people are already in the hospital when developing acute respiratory distress syndrome.


1. Overview
2. Acute respiratory distress syndrome and lung functionality
3. Cause
4. Risk factors
5. Symptoms
6. Complications
7. Diagnosis
8. Investigations
9. Treatment
10. Supportive care
11. Living with acute respiratory distress syndrome

Acute respiratory distress syndrome and lung functionality

To understand ARDS, you must know how the lungs work. When you breathe, air passes through the nose, mouth, trachea and then to the pulmonary alveoli. Air-bag walls are crossed by small blood vessels called capillaries. Oxygen flows through pulmonary alveoli’s capillaries and then into the bloodstream. Blood carries oxygen to all parts of the body, including its organs.

In ARDS, infections, injuries or other conditions cause pulmonary capillary leakage of air sachets, a larger quantity of liquid than normal. This prevents the lungs to fill with air and to carry enough oxygen in the bloodstream. When this happens, body organs do not receive necessary oxygen and without oxygen, they can’t work properly or work incompletely.

Most people who develop ARDS are hospitalized. Rarely those who are not in hospital suffer from other serious health diseases that cause ARDS, such as severe pneumonia. It is important that any person suffering from breathing problems to call emergency medical services.

Other synonyms of acute respiratory distress syndrome are acute lung injury, adult respiratory distress syndrome, pulmonary edema by increasing permeability, non-cardiac pulmonary edema.


Many conditions or factors may directly or indirectly affect the lungs and can lead to the development of ARDS. These could include:
- Sepsis – a condition characterized by bacterial infection of the blood flow
- Pneumonia – infection of the lungs
- Severe bleeding caused by an injury to the body
- Trauma in the upper body or head injury after a severe blow
- Breathing harmful vapors or fumes
- Inhalation of gastric contents after vomiting.

It is not clear why some people seriously ill or injured manifest ARDS and others do not. Researchers are still trying to find the causes of ARDS development and try to find new methods of treatment.

Risk factors

People who have a high risk of ARDS manifest, suffer from a disease or condition that may affect the lungs in a directly or indirectly manner.

- Direct lung injury – Among the diseases that can directly affect the lungs, include:

> breathing harmful vapors or fumes
> inhalation of gastric contents after vomiting
> use of a ventilator that supports breathing (sometimes this pressure can damage the lungs).
> situation in which a person drowns in a food, liquid or an object.

- Indirect injuries that can affect the lungs include:

> serious bleeding – caused by damage to the body after several blood transfusions
> chest or head trauma such as a severe blow
> pancreatitis – condition in which the pancreas becomes irritated or infected (pancreas is a gland that releases enzymes and hormones).
> fat embolism – condition in which fat is blocking an artery. It can be triggered by physical injury such as a broken bone.
> reaction to a drug.


Initial signs and symptoms of acute respiratory distress syndrome would be insufficient air reaches the lungs, shortness of breath and low blood oxygen. Other signs and symptoms depend on the cause of ARDS. They may occur before develop acute respiratory distress syndrome.

For example, if pneumonia is due to ARDS, it is possible that the patient to show cough and fever before this rapid breathing. Some people who develop acute respiratory distress syndrome have other signs and symptoms such as low blood pressure, confusion and extreme fatigue. This can mean that the body organs such as the kidneys and heart are not supplied with enough oxygen-rich blood.


If a person is diagnosed with ARDS, this can be caused by other medical problems during hospitalization. Most frequently may occur:

- Infections – being in hospital for a long time, there is risk of getting certain infections, such as pneumonia. Use of a ventilator for breathing increases the risk of infection.

- Pneumothorax – infection in whose case the air or gas is collected, in the space around the lungs, which could cause a lung dysfunction or both. Air pressure from a breathing ventilator can cause this condition.

- Lung scarring – ARDS causes stiffness (scarring) lungs. In this situation it will be difficult for the lungs to expand and fill with air. Using a fan can cause lung scarring.

- Blood clots – the horizontal position, maintained for long periods can cause blood clots in a person’s body. A blood clot that forms in a deep vein of the body is called deep vein thrombosis. This type of blood clot may detach, will travel to your lungs and block blood flow. This condition is called pulmonary embolism.


The doctor will diagnose acute respiratory distress syndrome based on medical history, physical examination and investigation results.

Medical history – the doctor will ask the patient if he suffer or if he has suffered from conditions that could lead to the development of ARDS. Also may request information about the presence of heart problems such as heart failure. Heart failure can cause fluid buildup in the lungs.

Physical examination – ARDS can cause abnormal sounds during breathing. The doctor will listen to your lungs with a stethoscope to detect the sounds. Also, the specialist will try to detect specific signs of fluid accumulation in various body parts. The doctor will see if the patient has bluish lips or skin. This means that blood has a low oxygen level, and this event is a possible sign of ARDS.


It is possible that the symptoms that a person manifests to belong to both ARDS and also other medical conditions, so the doctor may recommend one or more of the following tests:

- Initial tests – Measurement of gas pressure – this test measures blood oxygen levels from a blood sample taken from an artery. A low level of oxygen in the blood could be a sign of ARDS.

- X-ray radiography – Thanks to this investigation results images of structures in the chest, heart, lungs and blood vessels. By watching an X-ray image, the doctor can see if excessive fluid is present in the lungs.

- Blood tests – complete blood count, blood biochemistry and cultures help find the causes of ARDS, such as an infection.

- A sputum culture – this test is used to analyze sputum from the lungs resulting from cough. A sputum culture may help identify the cause of infection.

Other tests may include:

- Chest computerized tomography, or CT chest scan – this uses a computer to play detailed images of the lungs. A chest CT may show any lung problems such as fluid in the lungs, signs of pneumonia, a tumor, etc.

- Tests of the heart – with their help the doctor cab try to detect any signs of heart failure (a condition in which the heart can’t pump enough blood to meet the body’s needs). This condition can cause fluid buildup in the lungs.


ARDS is treated in a hospital unit, the intensive care unit. Current treatment approaches focus on improve blood oxygen levels and providing care measures. Doctors will try to identify and treat the primary cause of the disease.

Oxygen therapy – One of the main objectives of ARDS treatment is to deliver oxygen to the lungs and other organs (such as brain and kidney). Organs need oxygen to function properly. Usually oxygen is administered by nasal tube or through a mask that will be applied over the nose and mouth.

However, if the oxygen level does not rise or if the patient has difficulty breathing, the doctor will provide oxygen through a breathing tube, inserting the hose inside the mouth or nose and into the trachea. Before inserting the tube, the doctor will apply a local anesthetic to the patient’s neck and will provide an intravenously drug that will relax.

Breathing tube will be connected to a device (ventilator) to fill the lungs with oxygen-rich air. Your doctor will adjust the ventilator as needed to help the lungs to obtain the necessary amount of oxygen. If the patient requires long-term ventilator use, the doctor will make him a tracheotomy. Breathing tube will be inserted directly into the trachea and then will be connected to the ventilator.

Supportive care

Supportive care refers to treatment that may help relieve symptoms, prevent complications and improve quality of life. Among the support approaches used in ARDS treating, include:

- Medicines that help the patient relax, improve discomfort and pain treatment

- Continuous monitoring of heart and lung function

- Supplements – those who suffer from ARDS often suffer from malnutrition. Therefore, they will receive nutritional supplements through a tube.

- Treatment for infections – those who manifest ARDS have an increased risk of developing infections such as pneumonia. Using a ventilator, also increase the risk of infection. Doctors use antibiotics to treat pneumonia and so other infections.

- Preventing blood clots – maintaining body in a lying position for a long period of time can cause the formation of clots in the deep veins of the body. These clots can break off, can reach to the lungs and block blood flow. Anticoagulant medications and other treatments such as the application of compression stockings are used for their role to prevent blood clots.

- Prevention of intestinal bleeding – patients using long-term ventilator to support breathing have an increased risk of intestinal bleeding. Drug treatment may reduce this risk.

- Administration of fluids – to improve blood flow, hydration and nutritional purposes, the patient will be given fluids intravenously.

Living with acute respiratory distress syndrome

After treatment, some people heal of ARDS, but others continue to have long-term health problems. After the patient is discharged, on his home he may manifest one or more of the following problems:

- Shortness of breath – after treatment, pulmonary function recovers completely after 6 months. For some, this may take longer. In some cases, breathing problems may persist for the whole life.

- Fatigue and muscle weakness – ventilator use during hospitalization, can cause muscle weakness. Fatigue can also occur due to following treatment.

- Depression – many people who have suffered from ARDS feel depressed for a while after treatment.

- Memory difficulties and impaired clarity of thought – certain medications and low blood oxygen can cause these problems.

All these unpleasant events may disappear in a few weeks or a longer period of time.



Speak Your Mind


Current day month ye@r *