Assessment of neonatal platelet function using a viscoelastic technique.

The Sonoclot, a simple viscoelastometer, measures changes in the viscoelastic properties of plasma as it is recalcified. Platelet rich plasma (PRP) and platelet poor plasma (PPP) each have characteristic Sonoclot tracings. This technique was applied to evaluate the coagulability and platelet function, specifically, in PRP prepared from 53 normal term newborn cord bloods and whole blood from 17 very low birth weight premature infants. These values were compared to each other and to those previously reported adult control values obtained by one of the authors (C.B.). The cord PRP samples had shorter time related parameters than adult controls. The values from premature infants were suggestive of diminished platelet function when compared to cord values but were similar to adult values. This technique allows the use of small sample volumes, the minimization of the introduction of infection risks, and avoids manipulation of fragile, very premature infants.