ACUTE RESPIRATORY DISTRESS SYNDROME

Introduction

• Acute Respiratory Distress Syndrome (ARDS) is a respiratory disorder - also known as non-cardiogenic pulmonary edema, increased-permeability pulmonary edema, stiff lung, shock lung or acute lung injury, is a major cause of acute respiratory failure. 
• In general, the oxygen supply to the blood is cut off due to inflammation in the lungs. The alveoli (air sacs) in the lungs are responsible for supplying oxygen to the blood, which delivers it to the cells of the body. This inability of the alveoli in delivering oxygen results in less oxygen supply – leading to shortness in breath or respiratory failure. 
• In 1994 the American-European Consensus Conference (AECC) used the term “acute respiratory distress syndrome” instead of “adult respiratory distress syndrome” because the syndrome occurs in both adults and children. Year 1967 marked the first official description of ARDS by a group of pulmonary and critical care physicians at the University of Colorado. They reported it to be a non-cardiogenic form of pulmonary edema (leakage of fluid) characterized by the accumulation of both protein and cells in the alveoli in the presence of normal left ventricular filling pressures.

Complications of Disease

• ARDS leads to a buildup of fluid in the air sacs. This fluid prevents enough oxygen from passing into the bloodstream.


• The fluid buildup also makes the lungs heavy and stiff, and decreases the lungs' ability to expand. The level of oxygen in the blood can stay dangerously low, even if the person receives oxygen from a breathing machine (mechanical ventilator) through a breathing tube (endotracheal tube).


• ARDS often occurs along with the failure of other organ systems, such as the liver or the kidneys.


• There are some diagnosis complications due to bacterial infection in lungs. Usually, an underlying chest X- ray is done to confirm ARDS for inflammation. Therefore, bronchoscopy is done for bacterial analysis.

Symptoms & Signs

There are two pathways leading to acute respiratory distress syndrome (ARDS): a direct (pulmonary) insult that directly affects lung parenchyma, and an indirect (extra pulmonary) insult that results from an acute systemic inflammatory response. In the latter case, it is majorly due to bacterial infection. 

It is a multifactorial syndrome – the causative factors vary from patient to patient. Some of the known causes of ARDS can be:

• Pneumonia
• Sepsis (an overwhelming infection in the body)
• Aspiration of fumes, or chemicals
• Breathing vomit into the lungs (aspiration)
• Trauma
• Swelling in lungs

Survival Rate

It is life-threatening disorder which has a high mortality rate (40 per cent people die every year due to respiratory failure). It can affect people of any age. However, younger people have better chances to survive than elderly.

Causes & Risk factors

Smoking can put you at risk of developing ARDS. From studies conducted, it is evident that cigarette use increased the risk of ARDS. Also, puts alcohol consumers at risk.

Treatment Options

No drug has proved beneficial in the prevention or management of acute respiratory distress syndrome (ARDS). However, to keep the patients calm and comfortable often pain management coupled with dose of sedatives is given for temporary relief. Other than this supportive care in the Intensive Care Unit (ICU), such as mechanical ventilation and oxygen therapy comprises the basic treatment.