Umbilical lactate as a measure of acidosis and predictor of neonatal risk: a systematic review

Abstract

Background Umbilical cord lactate is one approach to measuring acidosis and intrapartum hypoxia, knowledge of which may be helpful for clinicians involved in the care of women and newborns.Objective To synthesise the evidence on accuracy of umbilical cord lactate in measuring acidosis and predicting poor neonatal outcome.Search strategy Studies published and unpublished between 1990 and 2014 from PubMed/Medline, EMBASE, Cochrane Central Register of Controlled Trials, and clinicaltrials.gov were assessed.Selection criteria Cross-sectional and randomised studies that assessed fetal acidosis (using lactate as the index test) with or without an assessment of neonatal outcome.Data collection and analysis Correlations between index and reference test(s) were recorded, as were the raw data to classify the predictive ability of umbilical lactate for neonatal outcomes. Metaanalysis of correlation was performed. We plotted estimates of the studies' observed sensitivities and specificities on Forest plots with 95% confidence intervals (CI). Where possible, we combined data using meta-analysis, applying the hierarchical summary receiver operating characteristics model and a bivariate model.Main results Twelve studies were included. Umbilical lactate correlated with pH [pooled effect size (ES) À0.650; 95% CI À0.663 to À0.637, P < 0.001], base excess (ES À0.710; 95% CI À0.721 to À0.699, P < 0.001), and Apgar scores at 5 minutes (ES 0.300; 95% 0.193-0.407, P < 0.001). Umbilical lactate had pooled sensitivity and specificity for predicting neonatal neurological outcome including hypoxic ischaemic encephalopathy of 69.7% (95% CI 23.8-94.4%) and 93% (95% CI 86.8-96.3%).Authors' conclusion Umbilical cord lactate is a clinically applicable, inexpensive and effective way to measure acidosis and is a tool that may be used in the assessment of neonatal outcome.

Critically ill neonates displayed stable vital parameters and reduced metabolic acidosis during neonatal emergency airborne transport in Sweden

“…As base deficit reflects the patient's total metabolic and circulatory status , the observed improvement might indicate that most patients' requirements were met during transport. This is reassuring given both the composition of the highly vulnerable study population and the fact that the median stabilisation time was significantly shorter than previously reported .…”

Effect of Oxygen vs Room Air on Intrauterine Fetal Resuscitation

“…We performed a randomized clinical trial to test the hypothesis that room air for category II fetal heart tracings is noninferior to oxygen in improving fetal metabolic status as represented by umbilical artery lactate, a marker of metabolic acidosis and neonatal morbidity. [17][18][19]…”

Impact of maternal HIV on umbilical cord lactate measurement at delivery in a South African labor ward

“…In addition, the use of antiretroviral therapy (ART) in pregnancy might affect the measurement of acidosis. A previous study found that umbilical artery lactate is an inexpensive and effective way to measure acidosis in the clinic and can be used in the assessment of neonatal outcome. Consequently, the aim of the present prospective cohort study was to assess umbilical artery lactate results (as a measure of acidosis) and intrapartum and neonatal outcomes among women with and without HIV who were delivering in a large tertiary unit in South Africa.…”

“…7 In addition, the use of antiretroviral therapy (ART) in pregnancy might affect the measurement of acidosis. A previous study 8 found that umbilical artery lactate is an inexpensive and effective way to measure acidosis in the clinic and can be used in the assessment of neonatal outcome.…”