Acute Respiratory Distress Syndrome: Causes, Symptoms, and Treatments
Acute respiratory distress syndrome (ARDS) is a severe respiratory disorder in which the air sacs (alveoli) of the lungs get filled up with fluid. The fluid interferes with the process of exchange of oxygen and carbon-dioxide between the lungs and the blood. This leads to decreased oxygen and increased carbon dioxide concentrations in the blood. If not treated promptly, this may lead to multi-organ failure.
ARDS is usually secondary to underlying conditions such as pneumonia, blood infections and other lung infections.
The common symptoms of ARDS include:
- Severe shortness of breath
- Extreme weakness
- Low blood pressure
- Rapid pulse rate
- Muscle fatigue
- Dry cough
The common causes of ARDS include:
- Severe blood infection
- Accidents causing chest, head, or neck injury
- Pneumonia or other chronic lung infections
- Overdose of sedatives or other antidepressant drugs
- Inhaling harmful toxic substances such as smoke, chemicals, saltwater or aspirating vomit
ARDS is a complication that may arise due to other disorders. The factors that increase the risk of ARDS include:
- Age over 65 years
- Underlying chronic lung disease
- Cigarette smoking
- Alcohol abuse
- Liver failure
- Toxic shock
- Recent surgery
- Recent chemotherapy
- Low protein levels in blood
- Using oxygen for a pre-existing lung condition
- Blood clots: The treatment for ARDS requires a hospital stay. Thus, lying in the hospital for a long duration may increase the risk of developing clots in the lower limbs. At times, these clots may get detached and reaches to the lungs and cause an obstruction of blood flow to the lungs. This life-threatening condition is referred to as pulmonary embolism.
- Infections: Longer hospital stay increases the risk of hospital-acquired infections. In addition, patients on an artificial airway (tracheostomy tube or endotracheal tube) are at increased risk of developing lung infections.
- Lung collapse (tension pneumothorax): In most cases of ARDS, when patient is on ventilator, the air volume and pressure of ventilator can force gas to leak through a small hole outside of the lung and causes lungs to collapse. When a patient is on mechanical ventilation, he/she is at high risk of lung injury. This will cause air to move from the lungs to the pleura (layer of tissue that envelopes the lung). The air does not allow the lungs to expand and causes lung collapse.
Diagnosis and Treatment
There is no specific test to confirm the occurrence of acute respiratory distress syndrome. The findings are based on the patient signs and symptoms and regular laboratory findings such as blood tests, image scans and heart tests.
- Image scan: Chest x-rays helps to reveal the affected portion of the lungs and how much it is affected and to see if there is enlargement of the heart. CT scan gives the detailed image of the heart and lung structures.
- Blood test: For ARDS, blood samples are collected from the artery rather than vein. This test is performed to evaluate the level of oxygen in the bloodstream. Other parameters evaluated may determine if you are anemic or suffering from any infections.
- Heart-related tests: Electrocardiography (ECG) and echocardiography are performed to rule out heart disorders, as the signs and symptoms of ARDS resemble cardiac disorders.
The goal of the treatment is to improve the oxygen-carrying capacity of the blood, treat infections and relieve symptoms such as pain and discomfort caused by the condition.
Oxygen supplementation enhances the volume of oxygen in the blood. This helps to regain the normal oxygen volume in the blood stream required for the tissues and organs to function normally.
- Supplemental oxygen: Oxygen is delivered through a mask fitted over the nose and mouth. Supplemental oxygen therapy is used to treat mild oxygen deficiency in blood.
- Mechanical oxygen: Oxygen is delivered through a mask fitted over the nose and mouth. In this procedure, the oxygen is forced into the lungs, which pushes out certain fluid from the air sacs.
The medication therapy is given to :
- Treat and prevent infections
- Relieve discomfort and pain
- Prevent clot formation in lungs and the lower limbs
- Reduces gastric reflux
Care should be taken to limit the administration of intravenous fluids. Too much of intravenous fluids can result in fluid accumulation within the air sacs, while too little intravenous administration may cause inadequate perfusion to the heart and to the vital organs of the body.
Long Term Management of ARDS
ARDS, although fatal in most cases, can be managed effectively. The overall health of the individual plays a major role in recovering from the condition. A young individual with trauma-induced ARDS may have better prognosis when compared to the older people.
Timely treatment, regular use of medications, and following certain lifestyle modifications are helpful in the long-term management of ARDS. However, it may take months to get completely cured from ARDS.
Prolonged treatment causes long-term damage such as:
- Damage to the lungs
- Muscle weakness
- Disturbed mental health
- Reduced quality of life
There is no specific way to prevent ARDS. However, timely treatment and preventing certain risk factors play a major role.
ARDS can be prevented through:
- Seeking complete treatment for injury, infection or trauma
- Avoiding cigarette smoking and second-hand smoke
- Avoiding alcohol consumption
- Getting vaccinated for common flu and pneumonia once a year and once in five years respectively
Nutrition plays a significant role in the management of acute respiratory distress syndrome. According to the recent research dietary oils, such as fish oil and borage oil, help balance pulmonary inflammation, thereby enabling to improve lung compliance and oxygenation.
1. Is discoloration of skin and nails common in people with acute respiratory distress syndrome?
Yes. Discoloration of skin and nails is one of the most common signs noticed in people with acute respiratory distress syndrome.
2. How can be a head injury associated with the risk of ARDS?
Accidents or sudden falls can cause damage to the portion of brain, which controls breathing, thus increasing the risk of acute respiratory distress syndrome (ARDS).
3. Can chronic pancreatitis cause acute respiratory distress syndrome (ARDS)?
Yes. Inflammation of the pancreas (pancreatitis) is often associated with increased risk of acute lung injury and ARDS.
4. Can ARDS cause pulmonary fibrosis?
ARDS could cause thickening or scarring of the lung tissue (pulmonary fibrosis). The scarring decreases the elasticity of the lung tissue and this affects the efficiency of the lungs.
5. Can people who survived ARDS experience problem with memory?
Yes. Individuals who are treated for ARDS might face cognitive problems and memory loss due to the use of sedatives and low oxygen levels in the blood.