Brain alkaline intracellular pH after neonatal encephalopathy

Ann Neurol. 2002 Dec;52(6):732-42. doi: 10.1002/ana.10365.


Experimental studies demonstrate an alkaline shift in brain intracellular pH (pH(i)) after hypoxia-ischemia (HI). In infants with neonatal encephalopathy after HI, our aims were to assess (1) brain pH(i) during the first 2 weeks after birth in infants categorized according to magnetic resonance imaging (MRI) during the first 2 weeks after birth and at more than 3 months of age, and neurodevelopmental outcome at 1 year; (2) the relationship between brain pH(i) and lactate/creatine; and (3) duration of alkaline brain pH(i). Seventy-eight term infants with neonatal encephalopathy were studied using MR techniques. One hundred and fifty-one studies were performed throughout the first year including 56 studies of 50 infants during the first 2 weeks after birth. pH(i) was calculated using phosphorus-31 MR spectroscopy and lactate/creatine was measured using proton MRS. The mean (standard deviation [SD]) brain pH(i) during the first 2 weeks after birth in infants with severely abnormal versus normal MRI was 7.24 (SD, 0.17) versus 7.04 (SD, 0.05; p < 0.001); in infants who subsequently developed cerebral atrophy versus those who did not: 7.23 (SD, 0.17) versus 7.06 (SD, 0.06; p < 0.05); in infants who died or had a severe neurodevelopmental impairment versus normal outcome: 7.28 (SD, 0.15) versus 7.11 (SD, 0.09; p < 0.05). Brain alkalosis was associated with increased brain lactate/creatine (p < 0.001). pH(i) remained more alkaline in the severe outcome group up to 20 weeks after birth (p < 0.05).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkalosis / metabolism*
  • Analysis of Variance
  • Brain / metabolism*
  • Brain / pathology
  • Brain Injuries / metabolism*
  • Brain Injuries / pathology
  • Creatine / analysis
  • Creatine / metabolism*
  • Follow-Up Studies
  • Humans
  • Hydrogen-Ion Concentration
  • Infant
  • Infant, Newborn
  • Intracellular Fluid / metabolism*
  • Lactic Acid / analysis
  • Lactic Acid / metabolism*
  • Logistic Models
  • Magnetic Resonance Imaging / methods
  • Prospective Studies


  • Lactic Acid
  • Creatine