PicmonicPatient 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%
The underlying abnormality in ARDS is increased permeability of the alveolar capillary membranes, which leads to the development of protein-rich pulmonary edema.
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
CXR will demonstrate air bronchograms
Treatment includes identification and management of underlying precipitation and secondary conditions
- Tracheal intubation with lowest level of PEEP is required to maintain the PaO2 above 60 mmHg or SaO2 above 90% in a patient with ARDS.
An air bronchogram appears when an infiltrate surrounds a peripheral bronchi, and is thus important in establishing lung consolidation.
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ARDS is a sudden and progressive failure of the respiratory system in which the alveolar-capillary membrane becomes damaged. Damage to this membrane makes it more permeable to fluid, which can lead to difficulty breathing, atelectasis, and hypoxemia that is unresponsive to oxygen therapy. Patients who develop ARDS are typically afflicted by another illness or injury such as COPD, pneumonia, tuberculosis, aspiration, sepsis, shock, or fluid overload. Patients with this condition may also develop pulmonary hypertension, which is a late indicator of decreased lung compliance. |
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Neonatal respiratory distress syndrome (NRDS) is a condition related to fetal lung immaturity in premature infants (<37 weeks gestational age) and a lack of surfactant. Infants with NRDS will exhibit signs of respiratory distress including tachypnea, nasal flaring, intercostal/substernal retractions, and audible grunting upon expiration. Interventions used to treat NRDS include administration of exogenous surfactant, oxygen therapy, and mechanical ventilation. It is important to note that infants with NRDS should not receive bottle or gavage feedings, as these may increase their respiratory rate and risk of aspiration. Instead, total parenteral nutrition (TPN) is used to provide the infant with adequate nutrients. |
Question 1 |
Atelectasis Hint: 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. | |
Diaphragmatic hernia Hint: Chest x-ray in a patient with a diaphragmatic hernia would not show a fine reticular granular pattern. | |
Respiratory distress syndrome | |
Pneumothorax Hint: Chest x-ray in a patient with a pneumothorax would not show a fine reticular granular pattern. |
Question 2 |
Tracheal intubation | |
Bilateral chest tube insertion Hint: See A for explanation. | |
Type-specific packed cells Hint: 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. | |
Colloid solutions Hint: Use of crystalloid solutions are preferred to avoid pulmonary edema. |
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