患儿，男，8天，因呼吸急促，面色苍白一小时入院。第一胎第一产，胎龄40周，因宫内窘迫行剖宫产，一分钟阿氏评分10分，出生体重4200g，生后随母亲住母婴同室。第9天时，突然呼吸急促，面色灰白，拒奶。查体：T36℃，口唇及甲床紫绀，呼吸60～70次／分，两肺呼吸音粗，心率200 Children, male, 8 days, due to shortness of breath, pale one hour admission. The first birth of the first child, gestational age 40 weeks, cesarean section due to intrauterine distress, one minute Alzheimer’s score of 10 points, birth weight 4200g, after living with mothers live in the same room. On the 9th day, a sudden shortness of breath, pale, refused to milk. Physical examination: T36 ℃, cyanotic lips and nail bed, breathing 60 to 70 beats / min, two lungs sound rough tone, heart rate 200