An increase in the premature newborns’ serum lactate content indicates the activation of glycolysis in cells. Persistent hyperlactataemia in premature newborns with extremely low birth weight is a consequence of profound metabolic changes. The decrease in lactate level in newborns with low birth weight during the neonatal period indicates the restoration of protective-compensatory forces of the organism. A high LDH level in new-borns at birth indicates the mitochondrial respiratory chain depression; adequate compensation of energy deficiency in the tissues causes a decrease in the LDH content in the neonatal period follow-up. In premature new-borns with extremely low birth weight, the prolonged increase in the activity of the “infarcted” LDH-HBDH isoenzyme and the decrease in the LDH/HBDH ratio has testified the decompensated tissue ischemia.
As markers of the new-born hypoxic-ischemic CNS injury severity, it is advisable to use the HBDH activity indicator and the LDH/HBDH ratio.