title: Postnatal laboratory timers of antenatal hypoxemic-ischemic brain damage.
abstract: OBJECTIVE
  Markers were sought to identify the antenatal starting times and rates at which brain damage advanced in children with hypoxemic-ischemic cerebral palsy.
  
  
  METHODS
  Fetal bradycardia's onset marked the damage's start. Using this baseline, the following were tested as additional timers of the damage's onset: serial blood counts of neonates' normoblasts, platelets, lymphocytes,differences at birth between base excess values in umbilical arterial and venous bloods,brain damage patterns.
  
  
  RESULTS
  Each timer had a broad antenatal time frame within which it could identify specific damage starting times. The broad time frames are as follows: Blood lymphocyte counts: 0.45 to 13.8 hours before birth, blood normoblast counts: 0.45 to 55.0 hours before birth, blood platelet counts: 0.5 to >72 hours before birth. Brain damage patterns: 0.4 to >0.7 hour before birth. Hyperventilating and hyperoxygenating neonates greatly accelerated the damage's advance.
  
  
  CONCLUSIONS
  Commonly obtained laboratory values and brain images can identify when such brain damage began and the rate at which it advanced.
authors.affiliation: Department of Pathology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, PA, USA.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Naeye
authors.forename: Michele L
authors.initials: ML
authors.lastname: Shaffer
mesh_terms: D001925:Brain Damage, Chronic / Q000196:embryology / Q000473:pathology; D002545:Brain Ischemia / Q000196:embryology / Q000473:pathology*; D002547:Cerebral Palsy / Q000196:embryology / Q000473:pathology*; D006801:Humans; D007231:Infant, Newborn; D018655:Lymphocyte Count; D010976:Platelet Count