Acute Respiratory Distress Syndrome Overview

Study Notes

Acute Respiratory Distress Syndrome (ARDS)

Characterized by damage to the alveolar membrane, leading to increased permeability and fluid accumulation in alveoli.
Results in decreased lung recoil and atelectasis, contributing to poor gas exchange.

Symptoms and Diagnosis

Refractory hypoxia occurs; significant oxygen deficiency despite oxygen supply.
Presents with bilateral infiltrates on imaging, indicating widespread lung involvement.
Non-cardiogenic pulmonary edema, distinct from cardiac causes due to altered permeability.

Risk Factors

Sepsis and COVID-19 among common triggers, with contributions from both direct and indirect lung injury.
Comorbidities play a crucial role in prognosis; increased fibrotic tissue leads to pulmonary hypertension.

Stages of ARDS

Injury Stage (Exudate): Initial damage and inflammatory response.
Reparative Stage (Proliferation): Opportunity for recovery, with most patients improving.
Fibrotic Stage: Characterized by worsening prognosis and persistent tissue damage.

Severe ARDS Symptoms

Indicators include decreased blood pressure (BP), decreased level of consciousness (LOC), metabolic acidosis, and reduced urine output (UO).
X-ray findings often show diffuse whiteout patterns, indicative of extensive lung involvement.
Auscultation may reveal crackles, with an imbalance leading to decreased oxygen (O2) and increased carbon dioxide (CO2).

Treatment and Management

Mechanical ventilation is often required for severe cases.
Prone positioning may enhance lung expansion and oxygenation, recommended for up to 16 hours.
Essential interventions include early ambulation and continuous renal replacement therapy (CRRT) for renal support.
Gastrointestinal ulcer prophylaxis is managed with H2 antagonists, proton pump inhibitors (PPIs), and sucralfate.
DVT prevention strategies include heparin or Lovenox, with alternatives like Eliquis if thrombosis occurs.

Infection Prevention Strategies

Maintain strict hand hygiene and elevate head of bed (HOB) at 30-45 degrees.
Conduct oral care using chlorhexidine (CHG) daily as part of a prevention bundle.
Consider sedation holidays to facilitate extubation when appropriate.

Complications of ARDS

Multiple Organ Dysfunction Syndrome (MODS) may occur, often associated with sepsis.
Respiratory complications include ventilator-associated pneumonia (VAP) and pulmonary embolism (PE).
Gastrointestinal issues such as ulcers, hemorrhage, and paralytic ileus are common.
Renal complications include acute kidney injury (AKI).
Central nervous system effects may present as delirium or PTSD.
Hematologic concerns involve disseminated intravascular coagulation (DIC) and anemia.
Cardiac complications may manifest as decreased cardiac output (CO) and dysrhythmias.
Long-term risks include tracheal complications from endotracheal tubes like ulcer stenosis and barotrauma.

Pharmacologic Therapy

Antibiotics for infection management.
Respiratory treatments and diuretics may be administered as needed.
Prone positioning is emphasized to improve respiratory outcomes.

Description

This quiz covers the essential aspects of Acute Respiratory Distress Syndrome (ARDS), including its progression from acute respiratory failure, the pathophysiology involved, and associated risk factors. Test your knowledge about how ARDS affects the alveolar membrane and its implications for oxygenation and pulmonary edema.