Acute respiratory distress syndrome resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ayokunle Olubaniyi, M.B,B.S [2]

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

Management

Characterize the symptoms: ❑ Chest pain ❑ Cough ❑ Cyanosis ❑ Diaphoresis ❑ Dyspnea ❑ Fever ❑ Hypotension ❑ Tachycardia ❑ Tachypnea

Patient evaluation: ❑ Obtain a detailed history: ♦ Age ♦ History of heart disease ♦ History of chest infection ❑ Examine the patient: ♦ Head/Neck - Neck veins (flat, no ↑JVP) ♦ Chest - No S3/S4, no murmurs ♦ Limbs - Hyperdynamic pulses, no edema

Urgent Labs: ❑ ABG ❑Calculate A-a gradient ❑ CBC ❑ Electrolytes ❑ BUN ❑ Creatinine ❑ CXR ♦ normal-sized heart ♦ Peripheral distribution of infiltrates ♦ Air-bronchogram (80%) Consider additional tests, if necessary: ❑ Bronchoalveolar lavage - gram stain, culture & cytology ❑ Bronchoscopy ❑ BNP - <100 pg/mL ❑ CT ❑ Echocardiography ❑ EKG - sinus tachycardia, non-specific ST-T wave changes ❑ Lung biopsy ❑ PAWP - <15 mmHg

Diagnostic Criteria - The Berlin Definition

Emergent therapy ❑ Pulse oximetry ❑ Administer 100% oxygen - non-rebreather face masks, nasal prongs ❑ Initiate management of the underlying precipitating factor ❑ Consider right heart catheterization if hypotension persists

❑ Check vital signs ❑ Assess hemodynamic status: ♦ RR<35 bpm ♦ PaC02 <35 mmHg ♦ Sp02 >88%

Stable

Unstable

❑ Maintain Sp02 between 88-95% by adjusting Fi02 ❑ Treat underlying disease

❑ Transfer ICU ❑ Intubate (indications) ❑ Mechanical ventilation protocol

Supportive treatment ❑ Analgesia - morphine ❑ Conservative fluid management ❑ Conscious sedation - lorazepam ❑ DVT prophylaxis ❑ Glucose control ❑ Nurse 30-45 degrees head-up position ❑ Nutritional support (enteral feeds) ❑ NPO (in severely ill) ❑ Prevent pressure ulcers ❑ Stress ulcer prophylaxis - PPI

Dos

• Nurse patient in semi-recumbent position (30-45 degrees) to reduce the risk of hospital-acquired pneumonia, especially those on enteral feeds.
• Conscious sedation and analgesia to reduce oxygen consumption.
• FiO2 is usually kept below 0.5 to reduce oxygen toxicity.
• Daily spontaneous breathing trials.