title: A new tool for the validation of umbilical cord acid-base data.
abstract: OBJECTIVE
  To identify the distribution of carbon dioxide tension (pCO(2) ) relative to pH in validated umbilical cord acid-base data.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  European hospital labour wards.
  
  
  METHODS
  Data for 36,432 term newborns were obtained from three sources: two trials of fetal monitoring with electrocardiography (ECG; the Swedish randomised controlled trial and the European Union Fetal ECG trial) and data from Mölndal Hospital.
  
  
  METHODS
  From the total study population, cases with missing values or obvious typing errors were excluded. The remaining data were validated based on specified criteria. Percentiles of arterial pCO(2) by pH were calculated using multilevel regression modelling.
  
  
  METHODS
  Umbilical cord pH, pCO(2) and base deficit.
  
  
  RESULTS
  Acid-base values were considered invalid in one out of seven cases. Percentiles for arterial pCO(2) corresponding to specified values of arterial pH were developed from the validated data of 26, 690 cases.
  
  
  CONCLUSIONS
  Percentiles for arterial pCO(2) for a specified arterial pH can be used as a tool to identify cases with erroneously low pCO(2) values, and thus avoid an incorrect interpretation of the newborn's acid-base status.
authors.affiliation: Department of Paediatric Research, Women and Children's Division, Oslo University Hospital Rikshospitalet, Oslo, Norway.
authors.forename: G A B
authors.initials: GA
authors.lastname: Kro
authors.forename: B M
authors.initials: BM
authors.lastname: Yli
authors.forename: S
authors.initials: S
authors.lastname: Rasmussen
authors.forename: H
authors.initials: H
authors.lastname: Norèn
authors.forename: I
authors.initials: I
authors.lastname: Amer-Wåhlin
authors.forename: O D
authors.initials: OD
authors.lastname: Saugstad
authors.forename: B
authors.initials: B
authors.lastname: Stray-Pedersen
authors.forename: K G
authors.initials: KG
authors.lastname: Rosén
mesh_terms: D000136:Acid-Base Equilibrium / Q000502:physiology*; D000137:Acid-Base Imbalance / Q000175:diagnosis; D002245:Carbon Dioxide / Q000097:blood*; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D015337:Multicenter Studies as Topic; D010313:Partial Pressure; D016032:Randomized Controlled Trials as Topic; D014469:Umbilical Arteries / Q000737:chemistry*; D014471:Umbilical Veins / Q000737:chemistry*
chemical_list: D002245:Carbon Dioxide