A full-term female newborn presents with excessive drooling. She is noted to have white, frothy mucus building up in her mouth and nose, which recurs despite suctioning. She is also unable to tolerate any feedings. During her first feeding, she gagged and immediately spit up. There were no complications during birth. On examination, the newborn is normotensive and has a normal heart rate. Her oxygen saturation is 98% but decreases to 80% during feeding. She has bilateral rales and rhonchi on lung auscultation. Her abdomen is distended and nontender.