Patient will present as → a patient brought to the emergency room with acute onset of dyspnea and tachypnea. He has a long history of alcoholism and was involved in a motor vehicle accident two days ago. He is hypoxic with crackles auscultated bilaterally and frothy pink sputum. Chest radiography reveals diffuse bilateral infiltrates which spare the costophrenic angle and air bronchograms, there is no cardiomegaly or pleural effusion noted. Oxygen saturation is 70%
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 (alcoholics), 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
- Rapid onset of profound dyspnea occurring 12-24 hours after the precipitating event
- Tachypnea, pink frothy sputum, crackles
Chest radiograph shows air bronchograms and bilaterally fluffy infiltrate
- Normal BNP, pulmonary wedge pressure, left ventricle function and echocardiogram
Treatment involves identifying and managing underlying precipitation and secondary conditions
- Tracheal intubation with the lowest level PEEP to maintain PaO2 > 60 mmHg or SaO2 > 90
- ARDS is often fatal, the risk increases with age and severity of illness
Small areas of atelectasis usually are asymptomatic. While larger areas may present with similar clinical findings, the chest x-ray findings are not consistent with atelectasis.
Chest x-ray in a patient with a diaphragmatic hernia would not show a fine reticular granular pattern.
Respiratory distress syndrome
Chest x-ray in a patient with a pneumothorax would not show a fine reticular granular pattern.
Bilateral chest tube insertion
Chest tube insertion is not indicated in a patient with ARDS.
Type-specific packed cells
Fluids are the preferred treatment initially for hypovolemia. Type-specific packed cells are given when the patient's blood type is identified. Until then O negative packed cells are administered.
Use of crystalloid solutions are preferred to avoid pulmonary edema.
Provide supplemental oxygen
Marked hypoxemia is refractory to treatment with supplemental oxygen in ARDS.