The answer is A – Tracheal intubation
This patient has ARDS after major trauma (profound dyspnea, bilateral infiltrates, normal heart size). Its shunt-driven hypoxemia does not correct with supplemental oxygen alone, so he needs tracheal intubation with lung-protective ventilation: 6 mL/kg predicted body weight, plateau pressure ≤30 cm H2O, PEEP set with a PEEP/FiO2 table, and a target SpO2 of 88–95%.
View blueprint lesson
Pearls
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by fluid collecting in the lungs depriving organs of oxygen
- The underlying abnormality in ARDS is ⇑ Permeability of alveolar-capillary membranes ⇒ development of protein-rich pulmonary edema (non-cardiogenic pulmonary edema)
- ARDS can occur in those who are critically ill or who have significant injuries
Three clinical settings account for 75% of ARDS cases:
- Sepsis syndrome (most common cause)
- Severe multiple trauma
- Aspiration of gastric contents (e.g., alcohol use disorder), toxic inhalation, near-drowning
People with ARDS have severe shortness of breath and often are unable to breathe on their own without support from a ventilator
- Occurring 12-24 hours after the precipitating event
- Tachypnea, pink frothy sputum, crackles
Diagnosis
Chest radiograph shows air bronchograms and bilaterally fluffy infiltrate
- Echocardiography (with BNP) excludes cardiogenic pulmonary edema: normal heart size and left ventricular function; a wedge pressure (PCWP) is no longer required for diagnosis
Treatment
- Treatment involves identifying and managing underlying precipitation and secondary conditions
- Tracheal intubation with lung-protective ventilation (6 mL/kg predicted body weight, plateau pressure ≤30 cm H2O, PEEP set with a PEEP/FiO2 table) targeting SpO2 88–95% (PaO2 55–80 mmHg); prone positioning (≥16 hours/day) for severe ARDS (PaO2/FiO2 <150); early corticosteroids are suggested in moderate–severe ARDS
- ARDS is often fatal, the risk increases with age and severity of illness
