title: Fetal cerebral energy metabolism and electrocardiogram during experimental umbilical cord occlusion and resuscitation.
abstract: OBJECTIVE
  The purpose of this experimental study was to elucidate alterations in fetal energy metabolism in relation to ECG changes during extreme fetal asphyxia, postnatal resuscitation and the immediate post-resuscitatory phase.
  
  
  METHODS
  Five near-term fetal sheep were subjected to umbilical cord occlusion until cardiac arrest followed by delivery, resuscitation and postnatal pressure-controlled ventilation. Four sheep served as sham controls and were delivered immediately after ligation of the umbilical cord. Fetal ECG was analysed online for changes of the ST segment. Fetal metabolism was monitored by intracerebral and subcutaneous microdialysis catheters.
  
  
  RESULTS
  Fetal ECG reacted on cord occlusion with an increase in the T-wave height followed by changes in intracerebral levels of oxidative parameters. Cerebral lactate/pyruvate ratio and glutamate increased to median (range) of 240 (200-744) and 34.0 (22.6-60.5) mmol/l, respectively; both parameters returned to baseline after resuscitation. Cerebral glucose decreased to 0.1 (0.08-0.12) mmol/l after occlusion and increased above baseline upon resuscitation. In subcutaneous tissue as well as blood the increase in lactate occurred with a delay compared to cerebral levels.
  
  
  CONCLUSIONS
  The fetal ECG changes related to asphyxia preceded the increase in excitotoxicity as determined by increase in cerebral glutamate during asphyxia. Cerebral lactate increase was superior to subcutaneous lactate increase.
authors.affiliation: Department of Clinical Sciences Lund, Lund University, Lund, Sweden. isis.amer-wahlin@ki.se
authors.forename: Isis
authors.initials: I
authors.lastname: Amer-Wåhlin
authors.forename: Anders
authors.initials: A
authors.lastname: Nord
authors.forename: Barbara
authors.initials: B
authors.lastname: Bottalico
authors.forename: Stefan R
authors.initials: SR
authors.lastname: Hansson
authors.forename: David
authors.initials: D
authors.lastname: Ley
authors.forename: Karel
authors.initials: K
authors.lastname: Marsál
authors.forename: Urban
authors.initials: U
authors.lastname: Ungerstedt
authors.forename: Carl Henrik
authors.initials: CH
authors.lastname: Nordström
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply / Q000196:embryology* / Q000378:metabolism; D001923:Brain Chemistry; D016887:Cardiopulmonary Resuscitation; D004195:Disease Models, Animal; D004562:Electrocardiography; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005311:Fetal Hypoxia / Q000209:etiology / Q000378:metabolism; D018698:Glutamic Acid / Q000032:analysis / Q000097:blood; D006323:Heart Arrest / Q000209:etiology / Q000378:metabolism*; D019344:Lactic Acid / Q000032:analysis / Q000097:blood; D011247:Pregnancy; D019289:Pyruvic Acid / Q000032:analysis / Q000097:blood; D012756:Sheep; D014470:Umbilical Cord / Q000502:physiology
chemical_list: D019344:Lactic Acid; D018698:Glutamic Acid; D019289:Pyruvic Acid