Acute Respiratory Distress Syndrome

Overview


Plain-Language Overview

Acute Respiratory Distress Syndrome (ARDS) is a serious lung condition that affects the ability to breathe and get enough oxygen into the blood. It happens when the lungs become severely inflamed and filled with fluid, making it hard for oxygen to pass into the bloodstream. This condition mainly affects the lungs and can cause symptoms like severe shortness of breath, rapid breathing, and low oxygen levels. ARDS often occurs after a major injury, infection, or illness that triggers widespread inflammation. The damage to the tiny air sacs in the lungs, called alveoli, leads to fluid leakage and poor oxygen exchange. Because of this, people with ARDS may need help breathing with a machine called a ventilator. The condition can be life-threatening and requires urgent medical care.

Clinical Definition

Acute Respiratory Distress Syndrome (ARDS) is a form of non-cardiogenic pulmonary edema characterized by diffuse alveolar damage and increased permeability of the alveolar-capillary barrier. It results from a direct or indirect insult such as sepsis, pneumonia, trauma, or aspiration, leading to an intense inflammatory response in the lungs. The hallmark pathology includes damage to type I and type II pneumocytes, disruption of the alveolar-capillary membrane, and accumulation of protein-rich edema fluid in the alveoli. This impairs gas exchange and causes severe hypoxemia refractory to oxygen therapy. Clinically, ARDS presents with acute onset of bilateral infiltrates on chest imaging, decreased lung compliance, and severe hypoxemia without evidence of left atrial hypertension. The syndrome is a major cause of respiratory failure in critically ill patients and is associated with high morbidity and mortality.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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