ABSTRACT. We report here a case of a 3-week-old infant with a lung disease of unknown origin who underwent diagnostic fiber-optic bronchoscopy. During the procedure, she developed unilateral pulmonary edema. Factors that contributed to this complication are discussed along with means to reduce its occurrence. Pediatrics 2004;113:e501-e503. URL: http://www. pediatrics.org/cgi/content/full/113/5/e501; infant, pulmonary edema, bronchoscopy.ABBREVIATION. NPPE, negative-pressure pulmonary edema. N egative-pressure pulmonary edema (NPPE) may develop whenever subatmospheric pressure is generated at the alveolar level. It usually occurs in young, muscular, adult subjects with an acute airway obstruction of various causes 1 and is unusual in neonates and young infants because of their compliant chest walls. We describe a 3-week-old infant in whom hypoxemia occurred during diagnostic fiber-optic bronchoscopy and who was subsequently diagnosed as having unilateral NPPE. To our knowledge, this is the first case report describing such a complication in a neonate after bronchoscopy. CASE REPORTA 3-week-old female infant was scheduled to have an elective diagnostic bronchoscopy. She was born at term via normal vaginal delivery with an Apgar score of 9 at 1 minute and 10 at 5 minutes. Soon after birth, she became slightly cyanotic (saturation: 80-82% on room air), was admitted to the neonatal intensive care unit, and was kept in a humidified oxygen tent (fraction of inspired oxygen: 30%). On this regimen she reached saturations of between 94% and 97%. Over the following days, she gradually developed hypercapnia with acidemia. The main physical finding was of wet inspiratory crackles over the lung bases. Blood cultures and serologic tests for toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus types 1 and 2, and other viruses all proved negative. Broad-spectrum antibiotics including macrolides did not change her clinical status. Repeated vomiting raised the possibility of gastroesophageal reflux, and cisapride was administered. A plain chest radiograph and computed tomography scan disclosed hyperinflation and bilateral infiltrates. Cardiac echo-Doppler showed no malformation. To rule out congenital alveolar proteinosis, or functional impairment of surfactant, it was decided to perform fiber-optic bronchoscopy.The infant was anesthetized with gradually increasing concentrations of halothane in oxygen using a fitted pediatric mask and a Jackson-Rees system. She was breathing spontaneously with the assistance of intermittent bag ventilation. Small boluses of propofol were administered whenever she reacted to airway manipulation. A 3.5-mm video-assisted bronchoscope was inserted via a 90°leak-tight swivel connector. Inspection showed normal trachea and left bronchial tree. Bronchoalveolar lavage was performed by wedging the right bronchus and instilling boluses of saline. Five milliliters of saline were instilled and immediately suctioned while withdrawing the bronchoscope upward. The suction port was connected to the wall...