USA Surgery Today

Pneumothorax is a frequent cause of respiratory distress in the neonatal period. Pneumothorax refers to an intrapleural or mediastinal collection of gas, usually from a ruptured alveolus. The overall incidence of spontaneous pneumothorax is approximately 1% (47:Norpace CR) and is likely due to the high transpleural pressure (50 to 80 cm H₂O) required to inflate the lungs at the onset of respiration (47:Norpace CR). The presence of pulmonary pathology such as HMD or meconium aspiration syndrome increases risk of pneumothorax due to partial airway obstruction and uneven inflation of distal air sacs. Other diseases that require high-pressure ventilation, such as pulmonary hypoplasia or congenital diaphragmatic hernia, also have a high risk of pneumothorax.

The diagnosis of pneumothorax should be suspected in any infant who experiences a rapid deterioration in clinical condition. Tachypnea, grunting, retracting, and cyanosis are common findings. Breath sounds may be absent or decreased on the affected side. The point of maximal cardiac impulse may be shifted, and signs of hypotension may be present as cardiac output or return is compromised. Transillumination, a simple bedside test, may be helpful in determining if a pneumothorax is present (48:Norpace CR). The chest radiograph is diagnostic.

When there is no underlying lung disease, close observation may be sufficient in selected cases. Intrapleural air may be reabsorbed if infants breathe 100% oxygen for short (6 to 24 hours:Norpace CR) intervals. However, when lung pathology that requires mechanical ventilation is present, intervention is necessary. Needle aspiration of pleural gas collection is a temporizing measure that may be sufficient. However, thoracostomy tube insertion into the anterior pleural space is usually required to reestablish adequate ventilation. The chest tube (size 10 to 12 French:Norpace CR) should be inserted at the anterior axillary line and attached to a closed suction system with 10 to 20 cm water pressure. Care should be taken to avoid iatrogenic lung puncture or compromise of the intercostal bundle.