Dec 25, 2008

Acute Respiratory Distress Syndrome

(ARDS, Acute Respiratory Distress Syndrome, Non-cardiogenic Pulmonary Edema)

Adult respiratory distress syndrome (ARDS) is a life-threatening lung condition. It is a form of breathing failure that can occur in very ill or severely injured people. It is not a specific disease. It starts with swelling of tissue in the lungs and build up of fluid in the tiny air sacs that transfer oxygen to the bloodstream. This leads to low blood oxygen levels.
ARDS is similar to infant respiratory distress syndrome, but the causes and treatments are different. ARDS can develop in anyone over the age of one year old.
If you suspect you or someone else has this condition, get medical help immediately.
Adult Respiratory Distress Syndrome

ARDS can be caused by many types of injuries, including:
• Direct injury to the lungs:
o Chest trauma, such as a heavy blow
o Breathing vomit
o Breathing smoke, chemicals, or salt water
o Burns
• Indirect injury to the lungs:
o Severe infection
o Massive blood transfusion
o Pneumonia
o Severe inflammation of the pancreas (pancreatitis)
o Overdoses of alcohol or certain drugs (eg, aspirin, cocaine, opioids, phenothiazines, and tricyclic antidepressants)
Lung and bone marrow transplantation–within few days of a lung transplant, the recipient is prone to development of ARDS.
Risk Factors
ARDS usually develops in people who are already in the hospital and are being treated for an injury listed above. However, only a small number of people who have these injuries actually develop ARDS. While no one can predict who will get ARDS, cigarette smokers, those with chronic lung disease, or those who are over age 65 are more at risk of developing ARDS.
If you experience any of these symptoms do not assume it is due to ARDS. These symptoms may be caused by other, more or less serious health conditions. If you or someone else is experiencing any one of them, seek medical help immediately:
• Shortness of breath
• Fast, labored breathing
• Bluish skin or fingernail color
• Rapid pulse
ARDS symptoms usually develop within 24-48 hours of the original injury.
Doctors may suspect ARDS when:
• A person suffering from severe infection or injury develops breathing problems
• A chest x-ray shows fluid in the air sacs of both lungs
• Blood tests show a low level of oxygen in the blood
• Other conditions that could cause breathing problems have been ruled out
The doctor will ask about symptoms and medical history, and perform a physical exam. People who develop ARDS may, however, be too sick to complain of symptoms. If a patient shows signs of developing ARDS, tests may include the following:
• Blood pressure check
• Blood tests for oxygen levels and signs of infection as well as levels of BNP (brain natriuretic peptide) a marker of heart failure
• Chest x-ray
• Analysis of coughed-up matter
• Occasionally, an echocardiogram (heart ultrasound), to rule out congestive heart failure
• Pulmonary artery catheterization to aid in diagnostic work-up
• Bronchoscopy to analyze airways. A labolatory examination may indicate presence of certain viruses, cancer cells etc.
• Open lung biopsy is reserved for cases when diagnosis is difficult ot establish
Talk with the doctor about the best treatment plan. Treatment options include the following:
• Treating the underlying cause or injury
• Providing support until the lungs heal:
o Mechanical ventilation (a breathing machine) through a tube placed in the mouth or nose, or through an opening created in the neck
o Monitoring blood chemistry and fluid levels
Often, ARDS patients are sedated to tolerate these treatments.
To help reduce your chances of getting ARDS, seek timely treatment for any direct or indirect injury to the lungs.