Hills B A, Masters I B, O'Duffy J F
Mater Children's Hospital, South Brisbane, Queensland, Australia.
Lancet. 1992 May 30;339(8805):1323-4. doi: 10.1016/0140-6736(92)91962-8.
The mechanism of recurrent cyanotic episodes in infants and children is not known, but a deficiency of surfactant is a possible cause. We have measured the amount of surfactant collected by bronchoalveolar lavage from two children with recurrent cyanotic episodes and from two controls with anatomical airway obstructions. We also assessed the physical properties of the surfactant by changing the surface area (A) of a monolayer and measuring its surface tension (gamma). The cases had lower amounts of surfactant extracted, which could explain some of the abnormalities of the gamma/A loops. However, the finding that the cases had reversed loops (ie, the surface tension is higher during monolayer compression than during expansion) shows that there is also a qualitative abnormality. These features suggest a possible diagnostic test if not a mechanism for this disorder.
婴幼儿反复出现发绀发作的机制尚不清楚，但表面活性剂缺乏可能是一个原因。我们测量了通过支气管肺泡灌洗从两名反复出现发绀发作的儿童和两名患有解剖学气道阻塞的对照者中收集的表面活性剂的量。我们还通过改变单层的表面积（A）并测量其表面张力（γ）来评估表面活性剂的物理性质。病例组提取的表面活性剂含量较低，这可以解释γ/A环的一些异常情况。然而，病例组出现反向环（即单层压缩期间的表面张力高于扩张期间）的发现表明还存在定性异常。这些特征表明，即使不是这种疾病的发病机制，也可能是一种诊断测试方法。
