Congenital emphysema: Mgmt

Congenital lobar emphysema is a disorder of lung parenchyma that results in hyperinflation of the lung and respiratory distress in infants from newborn to six months of age. It is a rare event with an incidence of 1 in 20,000-30,000. The left lung is more commonly involved and specifically the left upper lobe is the most commonly affected. The etiology is not known but speculation includes an intrinsic defect with lung tissue like abnormal or decreased bronchial cartilage or an external defect like compression from blood vessels or cysts.

On exam, these patients present with respiratory distress, tachypnea, oxygen desaturation and hyperinflation of the affected lung. Chest xray reveals a hyperinflated lobe of the lung. Vascular markings will help differentiate congenital emphysema from a pneumothorax. A CT scan may also be performed to further define the anatomy prior to surgical resection. The surgical resection is a lobectomy. This is typically performed through an open approach but there are reports of this being achieved thoracoscopically.

The primary concern with anesthesia is managing the airway in an infant with pre-existing respiratory compromise without making the respiratory distress worse. Anesthesia can be induced with volatile or intravenous agents. The classic teaching is to use inhalational agents and maintain spontaneous ventilation. Positive pressure ventilation may cause more respiratory compromise. However, if the infant is hypoventilating during the induction or maintenance of anesthesia, assisted ventilation may be required. After the induction of anesthesia the airway is secured with an endotracheal tube. Lung isolation is recommended to minimize inflation of the emphysematous lung. This can be achieved with an endobronchial intubation, bronchial blocker or a Fogarty catheter. Nitrous oxide is contraindicated. High frequency lung oscillation has been described. In addition to the standard ASA monitors, an arterial catheter and sometimes an central venous line are placed. The timing of the surgery and the ability to place these lines may depend on the hemodynamic and respiratory stability of the patient.

Postoperative analgesia can be achieved with a single injection caudal block or a caudally placed epidural catheter. Many of these patients can be extubated at the completion of surgery.