AMNIOTIC-FLUID SURFACE-TENSION IN COMPARI SON WITH THE L S-RATIO AS APREDICTOR OF FETAL LUNG MATURITY/

In 83 specimen of amniotic fluid both a dynamic measurement of the sur face tension by the Wilhelmy-balance and a determination of the lecith in-sphingomyelin-ratio were performed in 1987-1992 in order to predict a respiratory-distress-syndrome (RDS) of the newborn. 7 cases showed divergent results of both methods. In comparison with the measurement of surface tension by the Wilhelmy-balance, determination of the lecit hin/sphingomyelin-ratio showed more false positive results (4:1). Both methods provided false negative results in two cases each. In two cas es both methods showed false positive results, with RDS occurring in s pite of predicted lung maturity. In our high risk-collective 5 of 83 n ewbornes developed a severe RDS. All of them were delivered by caesare an section. A secondary deficiency of surfactant as a result of fetal hypoxia or acidosis as well as a possible influence of the way of deli very might be responsible for the development of RDS. The Wilhelmy-bal ance, which can be used as a bed-side-method, provides similar results in the prediction of fetal lung maturity compared to the L/S-ratio.