Fetal Scalp Lactate

FETAL SCALP LACTATE

Fetal scalp lactate testing has been shown to be as useful as pH with added benefits.

What level of lactate should trigger intervention in the first stage of labour?' What lactate level in the first stage of labour that indicates the need for intervention to ensure satisfactory outcomes for both babies and mothers.

Women in labour, with non-reassuring fetal heart rate traces are tested using fetal blood scalp sampling of 5 microL of capillary blood tested on an Accusport lactate meter.

Decision to intervene in labour is based on clinical assessment plus a predetermined cut off.

Main outcome measures are

· APGAR scores
· Cord arterial pH
· Meconium stained liquor and
· Intensive Care Nursery admission.

Scalp Lactate Level above 4.2 mmol/L shows optimal specificity, and sensitivity for predicting adverse neonatal outcomes.

Fetal blood sampling remains the standard for further investigating-non-reassuring cardiotocograph (CTG) traces. Even so, it is a poor predictor of fetal outcomes. Scalp lactate has been shown to be at least as good a predictor as scalp pH, with the advantages of being easier, cheaper and with a lower rate of technical failure. A cut off fetal scalp lactate level of 4.2 mmol/L, in combination with an assessment of the entire clinical picture, is a useful tool in identifying those women who need intervention.
The measurement of lactate in fetal blood scalp correlates to the fetal scalp Ph in the assessment of non reassuring fetal status. It may be an attractive alternative to pH analysis and a useful tool for monitoring fetal asphyxia, especially with the advent of handheld devices requiring small sample volumes.