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A new tool for the validation of umbilical cord acid-base data
G A B Kro1, B M Yli, S Rasmussen
1Department of Paediatric Research, Women and Children's Division, Oslo University Hospital Rikshospitalet, Oslo, Norway.
BJOG : an International Journal of Obstetrics and Gynaecology
|September 16, 2010
Summary
This study establishes reference percentiles for carbon dioxide tension (pCO2) in relation to pH using validated umbilical cord blood gas data. These percentiles help identify erroneous pCO2 values, improving the interpretation of newborn acid-base status.
Area of Science:
- Neonatal physiology
- Perinatal medicine
- Clinical chemistry
Background:
- Accurate interpretation of umbilical cord acid-base status is crucial for neonatal assessment.
- Existing data may contain inaccuracies affecting clinical decision-making.
- Establishing reliable reference ranges for key parameters like pCO2 is essential.
Purpose of the Study:
- To determine the distribution of carbon dioxide tension (pCO2) relative to pH in validated umbilical cord acid-base data.
- To develop percentile charts for arterial pCO2 based on arterial pH.
- To provide a tool for identifying potentially erroneous pCO2 measurements in newborns.
Main Methods:
- Observational study utilizing data from European hospital labor wards.
- Inclusion of 36,432 term newborns from clinical trials and hospital records.
- Validation of acid-base data, excluding invalid cases, followed by multilevel regression modeling to calculate pCO2 percentiles by pH.
Main Results:
- Approximately one in seven initially recorded acid-base values were deemed invalid.
- Validated data from 26,690 cases were used to generate pCO2 percentiles across a range of pH values.
- The study provides specific percentile data for arterial pCO2 corresponding to defined arterial pH levels.
Conclusions:
- Developed percentile charts for arterial pCO2 in relation to pH serve as a valuable clinical tool.
- These percentiles aid in identifying cases with potentially erroneous low pCO2 values.
- Improved identification of inaccurate pCO2 measurements can prevent misinterpretation of neonatal acid-base status.
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