每日一题_2023.05.13

A pregnant woman who suffers from hypertension and thrombocytopenia and has elevated liver function tests suddenly has a seizure. Suspecting eclampsia, the obstetrics team performs an emergency cesarean section. The neonate is delivered at 30 weeks and is found to have bradycardia. The child also appears to have labored breathing. He is rushed to the neonatal intensive care unit, where he is intubated and treated with steroids. Which of the following is a characteristic of the alveoli of this neonate’s lungs?

一名患有高血压和血小板减少症的孕妇，肝功能检查结果升高，突然出现癫痫发作。由于怀疑是子痫，产科团队实施了紧急剖宫产。新生儿在30周时分娩，发现心动过缓。这名儿童似乎也有呼吸困难。他被紧急送往新生儿重症监护室，在那里他被插管并接受类固醇治疗。下列哪项是该新生儿肺泡的特征?

(A)  An increased pressure is needed to collapse the lungs需要增加压力使肺萎陷

(B)  Increased surface tension表面张力增加

(C)  The lungs have increased compliance肺顺应性增加

(D)  The lungs lack a substance produced mainly by type I pneumocytes肺缺乏一种主要由I型肺细胞产生的物质

(E)  The lungs produce a substance with a lecithin:sphingomyelin ratio >1.5肺产生一种卵磷脂与鞘磷脂比值为1.5的物质

答案解析：

这个孩子患有NRDS，这是由于未成熟的新生儿肺不能产生表面活性物质的结果。表面活性剂在妊娠35周后大量产生。这种由ⅱ型肺细胞产生的物质主要含有磷脂和脱辅蛋白。它覆盖肺泡和小气道，降低气-水界面的表面张力。

正确答案：B