What is Acute Respiratory Distress Syndrome?

Causes of Acute Respiratory Distress Syndrome Explained

Acute Respiratory Distress Syndrome (ARDS) is a serious and potentially life‑threatening lung condition that causes fluid leakage in the lungs. This syndrome makes it difficult to breathe and prevents oxygen from reaching the body.

Accurate ARDS incidence estimates for India are limited; internationally, ARDS occurs in approximately 10–86 per 100,000 people annually.

Continue reading to learn more about this severe disease, along with its symptoms, causes, diagnosis, and treatment.

What Happens in the Acute Respiratory Distress Syndrome?

In acute respiratory distress syndrome, inflammation causes the lung's small air sacs (alveoli) to become filled with fluid due to injury to their protective membranes. This may restrict sufficient flow of air into the lungs, resulting in low oxygen content in the blood (hypoxia).

Consequently, essential organs such as the brain, heart, and kidneys cannot receive the oxygen they need to function properly. ARDS usually occurs quickly in ill or injured patients who need urgent medical intervention.

What are the Symptoms of Acute Respiratory Distress Syndrome?

The symptoms of ARDS vary based on the underlying cause and the severity of the condition, along with any pre-existing lung or heart issues. They consist of:

• Intense shortness of breath
• Increased heart rate
• A bluish tint to the fingernails and lips resulting from low blood oxygen levels
• Uncharacteristically laboured and rapid breathing
• Coughing
• Discomfort in the chest
• Confusion and profound fatigue

What are the Risk Factors of Acute Respiratory Distress Syndrome?

ARDS usually results from a severe illness or injury and is compounded by certain risk factors. Some notable causes and risk factors are:

• Toxic inhalation (e.g., smoke, chemicals, salt water, vomit)
• Severe infections of the lungs, for example, pneumonia
• Disseminated bloodstream infection (sepsis)
• Overdose on drugs, particularly sedatives or tricyclic antidepressants
• Severe trauma to the head or chest (e.g., motor vehicle accidents, sports injury)
• Age above 65 years
• Having a pre-existing chronic lung disease
• History of alcohol abuse or smoking
• Liver failure or toxic shock
• Critically ill or hospitalised with severe infection or trauma

How is Acute Respiratory Distress Syndrome Diagnosed?

Diagnosis for ARDS requires a history and physical evaluation of symptoms, excluding other conditions, imaging and lab tests for lung function and oxygen. Here’s a detailed overview:

• Physical Exam and History: Doctors will examine for symptoms like shortness of breath, rapid heart rate, etc., and perform a physical exam while searching for potential recent illness, infection, or trauma that could prompt ARDS.
• Chest X-ray: This test will demonstrate fluid in the lungs and allow the clinician to determine the extent of complete lung involvement.
• CT Scan: This examination will assess detailed cross-sectional images of the lungs and heart, both to evaluate structural damage and to exclude pleurisy or pneumonia.
• Arterial Blood Gas: This test measures the amount of oxygen and carbon dioxide in the blood, helping to identify the severity of hypoxia.
• Blood Tests: Blood tests will help identify possible underlying infections and assess organ function, as well as inflammation markers.
• Tests for Airway Secretions: This test identifies infections or pathogens in secretions that may have triggered the initial injury leading to ARDS.
• Electrocardiogram (ECG): It will be performed to better understand the electrical activity of the heart and exclude cardiac causes of respiratory distress.
• Echocardiogram: The doctor may perform an ultrasound of the heart to examine its structure and blood flow components, helping clinicians distinguish between ARDS and non-pulmonary aetiologies of respiratory distress (e.g., heart failure).

What is the Treatment for Acute Respiratory Distress Syndrome?

The following are the major treatment methods adopted to cure acute respiratory distress syndrome (ARDS):

• Supplemental Oxygen: Delivered by a face mask or nasal cannula in less severe cases to raise the oxygen level in the blood.
• Mechanical Ventilation: It is needed in most cases to support breathing, facilitate the delivery of oxygen into water-filled lungs, and lessen the workload on respiratory muscles.
• Extracorporeal Membrane Oxygenation (ECMO): ECMO provides temporary external oxygenation and carbon dioxide removal to support critically ill patients when ventilation is insufficient.
• Prone Positioning: Positioning a patient on their stomach with mechanical ventilation may enhance lung inflation and oxygenation.
• Fluid Management: Precise control of IV fluids is important to prevent fluid overload in the lungs while ensuring stable blood pressure and organ function.
• Medications: Acid‑suppressive medications may be used to reduce the severity of stress ulcers but do not prevent aspiration itself.

What are the 5 P’s of ARDS?

The 5 P's of ARDS (Acute Respiratory Distress Syndrome) treatment are:

• Perfusion
• Positioning
• Protective lung ventilation
• Protocol weaning
• Preventing complications
   

These standards guide supportive care provided to ARDS patients, aiming to improve oxygenation, minimise lung injury, and support recovery.

Acute Respiratory Distress Syndrome (ARDS) is a life-threatening condition that can be unpredictable, but with prompt identification and specialised treatment, a majority of patients can live through it and recover. Being aware of its aetiology, manifestations, and treatment helps individuals as well as healthcare specialists.

Also Read:

→ Acute Rheumatic Fever

→ Difference Between Rheumatoid Arthritis and Rheumatic Fever

→ Different Stages of Dengue Fever

→ Rheumatic Fever

→ Difference Between Fever and Hyperthermia