TRACHEAL ASPIRATES FROM NEONATES DURING ENDOTRACHEAL INTUBATION - DETECTION OF SURFACTANT BY POLARIZED-LIGHT MICROSCOPY

Abstract

A technique for detecting the presence of pulmonary surfactant in the tracheal aspirates obtained from preterm babies is described. The specimens were examined by means of polarized light microscopy. Surfactant could be simply and rapidly identified by its appearance as birefringent particles in volumes of aspirate as little as 1 microliter. Tracheal aspirate specimens from 108 babies, obtained on the first day of life, were examined without knowledge of the patient's clinical details. When the samples from each baby were subdivided into three groups on the basis of the amount of surfactant particles seen, this subgrouping corresponded well with the babies' ventilatory requirements at the ti..