1, neonatal respiratory distress syndrome: This syndrome is characterized by shortness of breath, moaning and dyspnea that worsens progressively from 2-6 hours after birth, with typical hairy glass-like changes in the chest X-ray. The peak of the disease is at 24-72 hours of life, which can be relieved by endotracheal intubation and intra-airway administration of pulmonary surface active substance replacement therapy, but some children with mild disease can also gradually improve after 72 hours of life without pulmonary surface active substance replacement therapy. 2, neonatal wet lung: also known as neonatal transient dyspnea or type II respiratory distress syndrome (RDStype II), is a self-limiting disease. Transient shortness of breath after birth, slightly similar to neonatal respiratory distress syndrome and amniotic fluid aspiration syndrome, but mostly seen in full-term or near-full-term elective cesarean section babies, with mild symptoms relieved within 2-5 days and a good prognosis. However, in recent years, severe cases of wet lung have also emerged, requiring treatment with a ventilator. 2. Aspiration pneumonia: It is common in newborns with intrauterine fetal distress and/or neonatal asphyxia, and is more common in full-term and near-full-term infants. Respiratory distress and cyanosis occur after resuscitation. The severity of clinical signs, symptoms and x-ray manifestations are related to the nature and amount of inhaled amniotic fluid. There is a wet rhythm on auscultation of the lungs. If inhaled meconium-like amniotic fluid can be combined with serious complications such as type II respiratory failure, persistent pulmonary hypertension and air leak in newborns. 3. Infectious pneumonia: can occur in utero, during labor and after birth. Intrauterine infectious pneumonia is transmitted by inhalation and blood transmission, usually with a history of maternal infection, premature rupture of membranes and other medical history, early birth with shortness of breath, moaning, unstable temperature and no cough. Some patients have pulmonary rales and coarse or diminished breath sounds. In severe cases, respiratory failure or manifestations of infection in other organ systems of the body, such as hepatosplenomegaly, jaundice, DIC, shock, intestinal paralysis, etc. may occur. 4. Esophageal atresia – esophagotracheal fistula: foaming at the mouth soon after birth, with a history of amniotic fluid excess. Vomiting, choking and cyanosis with respiratory distress immediately after the first feeding, with obstruction of gastric tube placement of about 8 cm or folding out of the mouth. Dilute iodography is feasible for diagnosis in highly suspicious patients.