PLASMA LACTATE CONCENTRATION AS A PREDICTOR OF DEATH IN NEONATES WITHSEVERE HYPOXEMIA REQUIRING EXTRACORPOREAL MEMBRANE-OXYGENATION

Plasma lactate concentrations have been used as an indicator of tissue hypoxia and as a predictor of the outcome of critical illness in adul ts. We evaluated the value of plasma lactate levels in predicting deat h in neonates with severe hypoxemia requiring extracorporeal membrane oxygenation (ECMO). We retrospectively reviewed the medical records in regard to plasma lactate levels and other clinical and biochemical me asurements in 28 consecutive neonates requiring ECMO from July 1992 to December 1993. Seven infants died (mortality rate, 25%); 21 infants w ere short-term survivors and 20 infants were discharged from the unit. The plasma lactate values for survivors and nonsurvivors, respectivel y, were 10.0 +/- 6.35 mmol/L vs 24.9 +/- 9.90 mmol/L on admission, and 13.7 +/- 6.32 mmol/L vs 38.4 +/- 9.20 mmol/L at peak (both p < 0.0000 1). The survivors had a significant decrease in plasma lactate levels 12 hours after the start of ECMO; the nonsurvivors had persistent, sev ere hyperlactatemia. Apart from being less acidotic, the survivors did not differ from the nonsurvivors in other clinical and biochemical me asurements. An admission plasma lactate concentration of <25 mmol/L pr edicted survival with a sensitivity 100%, a specificity 71.4%, and pos itive and negative predictive values of 91.3% and 100%, respectively. We conclude that plasma lactate levels could be useful in predicting d eath in neonates with severe hypoxemia requiring ECMO. Further prospec tive evaluations of the predictive value of plasma lactate levels in s ick neonates are required to confirm these initial observations.