Diseases

Your doctor will diagnose ARDS based on your medical history, a physical exam, and test results.Medical HistoryYour doctor will ask whether you have or have recently had conditions that could lead to ARDS.Your doctor also will ask whether you have heart problems, such as heart failure. Heart failure can cause fluid to build up in your lungs.Physical ExamARDS may cause abnormal breathing sounds, such as crackling. Your doctor will listen to your lungs with a stethoscope to hear these sounds.He or she also will listen to your heart and look for signs of extra fluid in other parts of your body. Extra fluid may mean you have heart or kidney problems.Your doctor will look for a bluish color on your skin and lips. A bluish color means your blood has a low level of oxygen. This is a possible sign of ARDS.Diagnostic TestsYou may have ARDS or another condition that causes similar symptoms. To find out, your doctor may recommend one or more of the following tests.Initial TestsThe first tests done are:

• An arterial blood gas test. This blood test shows the oxygen level in your blood. A low level of oxygen in the blood may be a sign of ARDS.
• Chest X-ray. This test is used to take pictures of the structures in your chest, such as your heart, lungs, and blood vessels. It can show whether you have extra fluid in your lungs.
• Blood tests, such as a complete blood count, blood chemistries, and blood cultures. These tests help find the cause of ARDS, such as an infection.
• A sputum culture. This test is used to study the spit you've coughed up from your lungs. A sputum culture can help find the cause of an infection.

Other TestsOther tests used to diagnose ARDS include:

• Chest computed tomography (to-MOG-rah-fee) scan, or chest CT scan. This test uses a computer to create detailed pictures of your lungs. A chest CT scan may show lung problems, such as fluid in the lungs, signs of pneumonia, or a tumor.
• Heart tests that look for signs of heart failure. Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. This condition can cause fluid to build up in your lungs.

ARDS is treated in a hospital's intensive care unit. Current treatment approaches focus on improving blood oxygen levels and providing supportive care. Doctors also will try to pinpoint and treat the underlying cause of the condition.Oxygen TherapyOne of the main goals of treating ARDS is to provide oxygen to your lungs and other organs (such as your brain and kidneys). Your organs need oxygen to work properly.Oxygen usually is given through nasal prongs or a mask that fits over your mouth and nose. However, if your oxygen level doesn't rise or it's still hard for you to breathe, your doctor will give you oxygen through a breathing tube. He or she will insert the flexible tube through your mouth or nose and into your windpipe.Before inserting the tube, your doctor will squirt or spray a liquid medicine into your throat (and possibly your nose) to make it numb. Your doctor also will give you medicine through an intravenous (IV) line in your bloodstream to make you sleepy and relaxed.The breathing tube will be connected to a machine that supports breathing (a ventilator). The ventilator will fill your lungs with oxygen-rich air.Your doctor will adjust the ventilator as needed to help your lungs get the right amount of oxygen. This also will help prevent injury to your lungs from the pressure of the ventilator.You'll use the breathing tube and ventilator until you can breathe on your own. If you need a ventilator for more than a few days, your doctor may do a tracheotomy (tra-ke-OT-o-me).This procedure involves making a small cut in your neck to create an opening to the windpipe. The opening is called a tracheostomy (TRA-ke-OS-to-me). Your doctor will place the breathing tube directly into the windpipe. The tube is then connected to the ventilator.Supportive CareSupportive care refers to treatments that help relieve symptoms, prevent complications, or improve quality of life. Supportive approaches used to treat ARDS include:

• Medicines to help you relax, relieve discomfort, and treat pain.
• Ongoing monitoring of heart and lung function (including blood pressure and gas exchange).
• Nutritional support. People who have ARDS often suffer from malnutrition. Thus, extra nutrition may be given through a feeding tube.
• Treatment for infections. People who have ARDS are at higher risk for infections, such as pneumonia. Being on a ventilator also increases the risk of infections. Doctors use antibiotics to treat pneumonia and other infections.
• Prevention of blood clots. Lying down for long periods can cause blood clots to form in the deep veins of your body. These clots can travel to your lungs and block blood flow (a condition called pulmonary embolism). Blood-thinning medicines and other treatments, such as compression stocking (stockings that create gentle pressure up the leg), are used to prevent blood clots.
• Prevention of intestinal bleeding. People who receive long-term support from a ventilator are at increased risk of bleeding in the intestines. Medicines can reduce this risk.
• Fluids. You may be given fluids to improve blood flow through your body and to provide nutrition. Your doctor will make sure you get the right amount of fluids. Fluids usually are given through an IV line inserted into one of your blood vessels.

• Acute lung injury
• Adult respiratory distress syndrome
• Increased-permeability pulmonary edema
• Noncardiac pulmonary edema
• ARDS used to be called stiff lung, shock lung, and wet lung.

If you have ARDS, you can develop other medical problems while in the hospital. The most common problems are:

• Infections. Being in the hospital and lying down for a long time can put you at risk for infections, such as pneumonia. Being on a ventilator also puts you at higher risk for infections.
• Pneumothorax (collapsed lung). This is a condition in which air or gas collects in the space around the lungs. This can cause one or both lungs to collapse. The air pressure from a ventilator can cause this condition.
• Lung scarring. ARDS causes the lungs to become stiff (scarred) and makes it hard for them to expand and fill with air. Being on a ventilator also can cause lung scarring.
• Blood clots. Lying down for long periods can cause blood clots to form in your body. A blood clot that forms in a vein deep in your body is called a deep vein thrombosis. This type of blood clot can break off, travel through the bloodstream to the lungs, and block blood flow. This condition is called pulmonary embolism.

Many conditions or factors can directly or indirectly injure the lungs and lead to ARDS. Some common ones are:

• Sepsis. This is a condition in which bacteria infect the bloodstream.
• Pneumonia. This is an infection in the lungs.
• Severe bleeding caused by an injury to the body.
• An injury to the chest or head, like a severe blow.
• Breathing in harmful fumes or smoke.
• Inhaling vomited stomach contents from the mouth.

It's not clear why some very sick or seriously injured people develop ARDS and others don't. Researchers are trying to find out why ARDS develops and how to prevent it.

ARDS, or acute respiratory distress syndrome, is a lung condition that leads to low oxygen levels in the blood. ARDS can be life threatening because your body's organs need oxygen-rich blood to work well.People who develop ARDS often are very ill with another disease or have major injuries. They might already be in the hospital when they develop ARDS.To understand ARDS, 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. Oxygen passes from the air sacs into the capillaries and then into the bloodstream. Blood carries the oxygen to all parts of the body, including the body's organs.In ARDS, infections, injuries, or other conditions cause the lung's capillaries to leak more fluid than normal into the air sacs. This prevents the lungs from filling with air and moving enough oxygen into the bloodstream.As a result, the body's organs (such as the kidneys and brain) don't get the oxygen they need. Without oxygen, the organs may not work well or at all.People who develop ARDS often are in the hospital for other serious health problems. Rarely, people who aren't hospitalized have health problems that lead to ARDS, such as severe pneumonia.If you have trouble breathing, call your doctor right away. If you have severe shortness of breath, call 9-1-1.

More people are surviving ARDS now than in the past. One likely reason for this is that treatment and care for the condition have improved. Survival rates for ARDS vary depending on age, the underlying cause of ARDS, associated illnesses, and other factors. Some studies estimate that the mortality rate for ARDS is 36% to 52% per 100,000 people, depending upon their current health condition.Some people who survive recover completely. Others may have lasting damage to their lungs and other health problems.Researchers continue to look for new and better ways to treat ARDS.

People at risk for ARDS have a condition or illness that can directly or indirectly injure their lungs.Direct Lung InjuryConditions that can directly injure the lungs include:

• Pneumonia. This is an infection in the lungs.
• Breathing in harmful fumes or smoke.
• Inhaling vomited stomach contents from the mouth.
• Using a ventilator. This is a machine that helps people breathe; rarely, it can injure the lungs.
• Nearly drowning.

Indirect Lung InjuryConditions that can indirectly injure the lungs include:

• Sepsis. This is a condition in which bacteria infect the bloodstream.
• Severe bleeding caused by an injury to the body or having many blood transfusions.
• An injury to the chest or head, such as a severe blow.
• Pancreatitis (PAN-kre-a-TI-tis). This is a condition in which the pancreas becomes irritated or infected. The pancreas is a gland that releases enzymes and hormones.
• Fat embolism (EM-bo-lizm). This is a condition in which fat blocks an artery. A physical injury, like a broken bone, can lead to a fat embolism.
• Drug reaction.