Acute Respiratory Distress Syndrome (ARDS)


Epidemiology

History

  • In 1967, Ashbaugh Introduced the Term “Respiratory Distress Syndrome”
    • Acute Onset of Tachypnea
    • Hypoxemia (see Hypoxemia, [[Hypoxemia]])
    • Diffuse Pulmonary Infiltrates
    • Decreased Lung Compliance
    • High Short-Term Adult Mortality Rates

Prevalence

  • LUNG SAFE Global Observational Study of ARDS in 50 Countries (JAMA, 2016) [MEDLINE]
    • Epidemiology
      • Approximately 10.4% of ICU Admissions Fulfilled ARDS Criteria
      • Approximately 23.4% of Mechanically Ventilated Patients Met ARDS Criteria
    • Clinical
      • Clinical Recognition of ARDS Ranged from 51.3% in Mild ARDS to 78.5% in Severe ARDS
    • Therapy
      • Less Than 66% of the Patients Received Tidal Volume <8 mL/kg
      • Proning was Only Used in 16.3% of Patients with Severe ARDS
    • Hospital Mortality Rates
      • Mild ARDS: 34.9%
      • Moderate ARDS: 40.3%
      • Severe ARDS: 46.1%
    • Conclusions: ARDS recognition and management has room for potential improvement

Risk Factors

  • Lung Injury Prediction Score (LIPS) Study (Am J Respir Crit Care Med, 2011) [MEDLINE]: multicenter observational cohort study (n = 5,584 patients at risk)
    • Acute Lung Injury Occurred at a Median of 2 Days in 6.8% of Patients
    • Acute Lung Injury Can Be Predicted Early in the Course of Illness Using Clinical Parameters
      • Aspiration: LIPS points +2
      • High-Risk Surgery
        • Aortic/Vascular: LIPS points +3.5
        • Cardiac: LIPS points +2.5
        • Acute Abdomen: LIPS points +2
        • Orthopedic Spine: LIPS points +1
      • High-Risk Trauma
        • Traumatic Brain Injury: LIPS points +2
        • Smoke Inhalation: LIPS points +2
        • Near Drowning LIPS points +2
        • Lung Contusion: LIPS points +1.5
        • Multiple Fractures: LIPS points +1.5
      • Pneumonia: LIPS points +1.5
      • Shock: LIPS points +2
      • Sepsis: LIPS points +1
      • Negative Risk Modifiers (Decrease the Risk of Acute Lung Injury)
        • Diabetes Mellitus: LIPS points -1 (Note: diabetes mellitus is the only risk factor which decreases the risk of developing ARDS)
      • Positive Risk Modifiers (Increase the Risk of Acute Lung Injury)
        • FIO2 >35%: LIPS points +2
        • pH <7.35: LIPS points +1.5
        • Tachypnea with RR >30: LIPS points +1.5
        • Alcohol Abuse: LIPS points +1
        • Obesity with BMI >30: LIPS points +1
        • Hypoalbuminemia: LIPS points +1
        • Chemotherapy: LIPS points +1
        • SpO2 <95%: LIPS points +1
  • Emergency Department Lung Injury Prediction Score Study (EDLIPS)/LIPS-1 Study (Int J Emerg Med, 2012) [MEDLINE]
    • Incidence of Acute Lung Injury was 7%
    • EDLIPS (Obtained Early in ED Course) Discriminated Patients Who Developed Acute Lung Injury Better than APACHE II Scoring and Similar to Original LIPS Score

Etiology

Infection

General

Viral Pneumonia

Bacterial Pneumonia

Fungal Pneumonia

Parasitic Pneumonia

Aspiration

Trauma/Surgery

Mechanical Pulmonary Edema

Hemodynamic Disturbance

Hematologic Disorder

Neurogenic Pulmonary Edema (see Neurogenic Pulmonary Edema, [[Neurogenic Pulmonary Edema]])

Rheumatologic Disease

Lung Transplant Rejection/Dysfunction (see Lung Transplant Rejection, [[Lung Transplant Rejection]])

Drug

Toxin

Other


Physiology


Pathology

Diffuse Alveolar Damage (DAD)


Diagnosis

Blood Culture (see Blood Culture, [[Blood Culture]])

Sputum Culture (see Sputum Culture, [[Sputum Culture]])

Bronchoscopy (see Bronchoscopy, [[Bronchoscopy]])

Echocardiogram (see Echocardiogram, [[Echocardiogram]])

Swan-Ganz Catheter (see Swan-Ganz Catheter, [[Swan-Ganz Catheter]])

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

FloTrac (see FloTrac, [[FloTrac]])

Suggested Diagnostic Work-Up for Unusual Pathogens/Etiologies of ARDS


Clinical: Berlin Definition of Acute Respiratory Distress Syndrome (ARDS) (JAMA, 2012) [MEDLINE]

Criteria for the Diagnosis of ARDS


Clinical Manifestations

Pulmonary Manifestations

Barotrauma

Bilateral Infiltrates

Hypoxemia (see Hypoxemia, [[Hypoxemia]])

Bronchospasm (see Obstructive Lung Disease, [[Obstructive Lung Disease]])

Decreased Lung Compliance (see xxxx, [[xxxx]])

Diffuse Alveolar Hemorrhage (DAH)(see Diffuse Alveolar Hemorrhage, [[Diffuse Alveolar Hemorrhage]])

Pulmonary Hypertension (see Pulmonary Hypertension, [[Pulmonary Hypertension]])

Other Manifestations

Neurologic Manifestations


Prevention

Aspirin (see Acetylsalicylic Acid, [[Acetylsalicylic Acid]])

Corticosteroids (see Corticosteroids, [[Corticosteroids]])


Treatment

Bronchodilators

Agents

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Corticosteroids (see Corticosteroids, [[Corticosteroids]])

Clinical Efficacy

General Recommendations

Recommendations (American College of Critical Care Medicine Consensus Statement on the Diagnosis and Management of Corticosteroid Insufficiency in Critically Ill Adult Patients, Crit Care Med, 2008) [MEDLINE]

Fluid Management

Rationale

Exclusion Criteria for Diuresis of the ARDS Patient

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Oxygen (see Oxygen, [[Oxygen]])

Clinical Efficacy

Sedation (see Sedation, [[Sedation]])

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Paralysis (Neuromuscular Junction Blockade) (see Neuromuscular Junction Antagonists, [[Neuromuscular Junction Antagonists]])

Epidemiology

Administration

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Lung Protective (Low Tidal Volume and Minimization of Plateau Pressure) Ventilation Strategy

Rationale

Administration

Clinical Efficacy

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Positive End-Expiratory Pressure (PEEP) (see PEEP + Auto-PEEP, [[PEEP + Auto-PEEP]])

Rationale

Administration

Clinical Efficacy

General Recommendations

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Esophageal Pressure-Guided Mechanical Ventilation

Rationale

Administration

Clinical Efficacy

Recruitment Maneuvers

Rationale

Clinical Efficacy

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

High-Frequency Ventilation (HFV) (see High-Frequency Ventilation, [[High-Frequency Ventilation]])

Techniques

Clinical Efficacy

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Pressure Control Ventilation (PCV) (see Pressure Control Ventilation, [[Pressure Control Ventilation]])

Rationale

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Pressure Control-Inverse Ratio Ventilation (PC-IRV) (see Pressure Control Ventilation, [[Pressure Control Ventilation]])

Rationale

Potential Adverse Effects

Administration

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Airway Pressure Release Ventilation (APRV) (see Airway Pressure Release Ventilation, [[Airway Pressure Release Ventilation]])

Clinical Efficacy

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Body Position -> Proning

History

Physiologic Mechanisms

Unknown Aspects of Proning

Technique

Practical Application

Absolute Contraindications to Proning

Relative Contraindications to Proning

Adverse Effects/Complications of Proning

Clinical Efficacy

Recommendations (2012 Surviving Sepsis Guidelines; Crit Care Med, 2013) [MEDLINE]

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Body Position -> Head of Bed at ≥30°

Rationale

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Body Position -> Continuous Lateral Rotational/Kinetic Bed Therapy

History

Rationale

Administration

Clinical Efficacy

Inhaled Nitric Oxide (iNO) (see Nitric Oxide, [[Nitric Oxide]])

Rationale

Administration

Adverse Effects

Clinical Efficacy

Avoidance of Systemically-Active Vasodilators

Venovenous Extracorporeal Membrane Oxygenation (VV-ECMO), Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO), and ECCO2R (see Venovenous Extracorporeal Membrane Oxygenation, [[Venovenous Extracorporeal Membrane Oxygenation]] and Venoarterial Extracorporeal Membrane Oxygenation, [[Venoarterial Extracorporeal Membrane Oxygenation]])

Indications from NEJM, 2011 Review of ECMO in ARDS [MEDLINE]

Absolute Contraindications

Relative Contraindications (NEJM, 2011) [MEDLINE]

Technique

Clinical Efficacy

Recommendations (American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guidelines for Mechanical Ventilation in ARDS) (Am J Respir Crit Care Med, 2017) [MEDLINE]

Tracheostomy (see Tracheostomy, [[Tracheostomy]])

Clinical Efficacy

Early Mobilization/Rehabilitation

Clinical Efficacy

Nutritional Support

Rationale

Clinical Efficacy

Recommendations (Society of Critical Care Medicine, SCCM, and American Society for Parenteral and Enteral Nutrition, ASPEN, 2016 Guidelines) [MEDLINE]

Weaning

Recommendations (2016 Surviving Sepsis Guidelines; Intensive Care Med, 2017) [MEDLINE]

Therapies with Unclear or No Clinical Benefit in ARDS


Prognosis

Reported Acute Respiratory Distress Syndrome (ARDS) Mortality Rates

Predicted Duration of Mechanical Ventilation in Acute Respiratory Distress Syndrome (ARDS) Survivors by Berlin Definition Class [MEDLINE]

Predictors of Acute Respiratory Distress Syndrome (ARDS) Mortality

Post-Operative Acute Respiratory Distress Syndrome (ARDS) Mortality


Sequelae of Acute Respiratory Distress Syndrome (ARDS)

Exercise Limitation/Physical Dysfunction

Decreased Quality of Life (QOL)

Increased Costs and Use of Health Care Services

Neuropsychologic Dysfunction


References

General

Epidemiology

Etiology

Infection

Hematologic Disorder

Clinical

Pulmonary Hypertension (see Pulmonary Hypertension, [[Pulmonary Hypertension]])

Prevention

Treatment

General

Bronchodilators

Corticosteroids (see Corticosteroids, [[Corticosteroids]])

Oxygen (see Oxygen, [[Oxygen]])

Paralysis (Neuromuscular Junction Blockade) (see Neuromuscular Junction Antagonists, [[Neuromuscular Junction Antagonists]])

Fluid Management

Low Tidal Volume Ventilation

Positive End-Expiratory Pressure (PEEP) (see PEEP + Auto-PEEP, [[PEEP + Auto-PEEP]])

Esophageal Pressure-Guided Mechanical Ventilation

Recruitment Maneuvers

High-Frequency Ventilation (HFV) (see High-Frequency Ventilation, [[High-Frequency Ventilation]])

Pressure Control-Inverse Ratio Ventilation (see Pressure Control Ventilation, [[Pressure Control Ventilation]])

Airway Pressure Release Ventilation (APRV) (see Airway Pressure Release Ventilation, [[Airway Pressure Release Ventilation]])

Partial Liquid Ventilation

Body Position -> Proning

Body Position -> Head of Bed at 30°

Body Position -> Continuous Lateral Rotational/Kinetic Bed Therapy

Inhaled Nitric Oxide (iNO) (see Nitric Oxide, [[Nitric Oxide]])

Venovenous Extracorporeal Membrane Oxygenation (VV-ECMO) (see Venovenous Extracorporeal Membrane Oxygenation, [[Venovenous Extracorporeal Membrane Oxygenation]])

Tracheostomy (see Tracheostomy, [[Tracheostomy]])

Early Mobilization/Rehabilitation

Nutritional Support

Activated Protein C

Macrolides (see Macrolides, [[Macrolides]])

Prognosis