Objective: To compare the measurement of lactate in fetal scalp and umbilical artery blood by a new dry reagent strip method with a commercially available enzymatic method using plasma (Monotest).
Design: Comparative study.
Subjects: Fetal scalp blood samples were obtained during labour from 24 fetuses and umbilical artery blood samples were obtained at birth in a further 51 deliveries.
Results: The concentration of lactate in scalp and umbilical artery blood measured by the reagent strip method correlated well (r = 0.94, P less than 0.001 and 0.95, P less than 0.001 respectively) with the enzymatic plasma method. The paper strip method tended to give lower readings than the enzymatic method when the fetal haematocrit was greater than or equal to 50%.
Conclusions: The new dry reagent strip method which takes only 1 min to carry out and requires only 20 microliters of blood seems to be handy and reliable. This system provides a convenient and rapid test for measuring fetal blood lactate.