A protocol for the routine measurement of lactate and pyruvate in cord blood.

The influence of the site of sampling and the delay in sample collection on cord blood concentrations of lactate and pyruvate were investigated. A delay in sample collection of greater than 1 min after cord clamping could invalidate the results obtained. Samples from umbilical artery had higher lactate values (mean 3.13 mmol/l) than paired vein samples (mean 2.32 mmol/l) but there were no significant differences in lactate values between different sites sampled within the umbilical vein. A calculation was devised to circumvent the need to take cord blood samples immediately after delivery.