Acute Respiratory Distress syndrome (ARDS):
Common causes of Acute Respiratory Distress Syndrome mnemonic
Acute respiratory distress syndrome (ARDS) is respiratory failure from a systemic disease or an overwhelming lung injury which leads to severe hypoxia. ARDS causes Diffuse alveolar damage that causes an increase in alveolar capillary permeability which results in leakage of protein rich fluid into alveoli, forming intra-alveolar hyaline membrane.
ARDS is idiopathic. A large number of illnesses and injuries are associated with ARDS and they include:
- Aspiration of gastric content
- Acute pancreatitis
- Air embolism
- Amniotic embolism
- Radiography
- Drug overdose
- DIC
- near Drowning
- Sepsis
- Shock
- Smoke inhalation
Diagnostic Tests for ARDS:
ARDS is defined as having a pO2/FIO2 ratio under 300.
Imaging
- Chest X-ray. A chest X-ray can reveal which parts of your lungs have fluid in them and whether your heart is enlarged. Chest X-ray may also show Shows bilateral infiltrates “white out”.
- Computerized tomography (CT). A CT scan combines X-ray images taken from many different directions into cross-sectional views of internal organs. CT scans can provide detailed information about the structures within the heart and lungs.
Lab tests
- A test using blood from an artery in your wrist can measure your oxygen level. Other types of blood tests can check for signs of infection or anemia. If your doctor suspects that you have a lung infection, secretions from your airway may be tested to determine the cause of the infection.
Heart tests
Because the signs and symptoms of ARDS are similar to those of certain heart problems, your doctor may recommend heart tests such as:
- Electrocardiogram. This painless test tracks the electrical activity in your heart. It involves attaching several wired sensors to your body.
- Echocardiogram. A sonogram of the heart, this test can reveal problems with the structures and the function of your heart.
Treatments and drugs
The first goal in treating ARDS is to improve the levels of oxygen in your blood. Without oxygen, your organs can’t function properly.
Mechanical Ventilation
- Low tidal-volume mechanical ventilation is the best support while waiting to see if the lungs will recover.
- Positive end-expiratory pressure (PEEP) is used when the patient is undergoing mechanical ventilation to try to decrease the FIO2. Levels of FIO2 above 50% are toxic to the lungs.
Fluids
- Carefully managing the amount of intravenous fluids is crucial. Too much fluid can increase fluid buildup in the lungs. Too little fluid can put a strain on your heart and other organs, and lead to shock.
Medication
Patients with ARDS usually are given medication to:
- Prevent and treat infections
- Relieve pain and discomfort
- Prevent clots in the legs and lungs
- Minimize gastric reflux
References:
- ARDS: http://www.mayoclinic.com/health/ards/DS00944
- Master the boards 2nd edition 2o13 by Conrad Fischer.