What is Acute Respiratory Distress Syndrome?
Acute respiratory distress syndrome, or ARDS, the malignant inflammation of the lungs, and develops as a response to an infection or infection. Recently, our understanding of the pathophysiology of this condition has improved a lot and has led to better medical interventions. Since this is one of the major causes of respiratory failure and morbidity in a hospital setting, nurses should ideally have a good knowledge about this acute lung injury.
Causes
- Pneumonia
- Aspiration
- Sepsis
- Shock
- Multiple trauma
- Pulmonary trauma
- Multiple transfusions
- Pancreatitis
The inflammatory response seen in ARDS is most often out of control and it may damage the healthy tissues in the body. It may lead to tissue damage even before repair sets in.
Malignant inflammation of the lungs may lead to any one of the following four events:
- Vasodilation
- Capillary permeability
- Clotting
- Vasoconstriction
As vasodilation is the first event in ARDS, it may maintain the oxygen supply for the patient. Capillary permeability allows the leakage of white blood cells and proteins into the injury area. This results in pulmonary edema which may be manifested as the ‘white out’ area in a chest x-ray. Once the clotting events are activated, it results in numerous microclotting throughout the lungs. A large number of pulmonary emboli develop, leading to hypoxemia. The lungs respond to the low oxygen supply by constricting the vessels or vasoconstriction.
Diagnosis
Some of the criteria for the diagnosis of this condition include:
- Presence of identifiable risk factor
- Diffuse, bilateral lung infiltrates on CXR
- Refractory hypoxemia
- pO2:FiO2
