Adult Respiratory Distress Syndrome 

ARDS develops when the small, elastic air sacs in the lungs, called alveoli, fill up with fluid. This occurs when the protective membrane of these alveoli become compromised due to inflammatory changes which occur under certain situations.

When the alveoli are filled with fluid, then oxygen can't be transported from the lungs to the bloodstream of the body. This problem is most probably the most common complication in critically ill patients or those who have sustained injuries which compromise their breathing.

The prognosis of patients with ARDS varies depending on the patient's age and how ill they are. It can therefore vary from the patient recovering completely to being fatal.

High risk patients for ARDS would then include those who are hospitalized, are critically ill and have sepsis, as well as those who have a chronic history of alcohol misuse.

Causes

These are the most common associated causes or ARDS:

• Severe pneumonia - this condition can affect all collective five lobes of the lungs.
• Breathing in of certain substances - inhaling high concentrations of chemical fumes or smoke can lead to ARDS.
• Aspiration - inhaling vomit or other stomach contents can cause issues such as aspiration pneumonia which complicates to ARDS.
• Major injuries - injuries, especially those involving the chest and the head, can result in ARDS due to direct damage to the lungs and the area of the brain involved with breathing, respectively.

Symptoms

The intensity of the symptoms of ARDS can vary depending on what the cause is, as well as how severely the lungs are affected. These can include the following:

• Severe shortness of breath (dyspnoea).
• Extreme tiredness and confusion.
• Unusually rapid and laboured breathing.
• Low blood pressure (hypotension).

READ Anxiety, Depression and Self-Abandonment

Complications

As mentioned, some patients can recover completely from ARDS. There are patients however who do develop complications, and these can include the following issues:

• Pneumothorax - ventilators are used to help the patient breath and at the same time apply pressure on the fluid in the alveoli so that it can be driven out of the lungs. These machines can unfortunately exert pressure, which forces gas through the outer membrane of the lung, and cause it to collapse.
• Pulmonary fibrosis - thickening or scarring of the tissue between the air sacs can occur a few weeks after ARDS developed in the patient. This can result in the lungs becoming stiffer which makes oxygen transport to the bloodstream more difficult.
• Infections - pneumonia can occur due to bacteria breeding in the airway secretions which can be transferred from the intubated pipe in the trachea to the lung tissue.
• Thromboembolic events - lying still in a bed while attached to a ventilator can increase the chances of developing clots in the deep venous system of the lower legs. These clots can then break off and lodge in the pulmonary arteries thus obstructing blood flow to the lungs.
• Cognitive, memory and emotional issues - ARDS can lead to low oxygen levels in the body and therefore compromise oxygen to the brain. This can result in cognitive issues and memory loss in these patients. These patients also report going through a period of depression.