Abstract
Objective
Umbilical cord arterial blood gas analysis is important for neonatal assessment at
birth, particularly for determining asphyxia. In April 2019, our labor ward faculty
held systemic teaching sessions for midwives, aimed to describe and to exercise proper
sampling from both the umbilical cord artery and vein, to ensure biological validity
of the values obtained. Our aim was to estimate the rates of inadequate umbilical
blood sampling and to evaluate the effect of guided training on the quality of sampling.
Study design
This retrospective interventional cohort study included all the women admitted to
the delivery room, with a record of postpartum umbilical cord blood sampling. Umbilical
cord sampling was considered adequate if two measurements were recorded with a veno-arterial
pH gradient of at least 0.02 and an arterio-venous pCO2 gradient of no less than 0.5 kPa. Rates of inadequate sampling were compared between
women who gave birth in the year preceding and the year following the guidance. Clinical
characteristics were compared between the groups of adequate and inadequate sampling.
Results
Overall, 3,779 women gave birth in the year preceding guidance, and 3,649 in the subsequent
year. Of these, 1,112 (29.4%) and 1,105 (30.2%), respectively, underwent umbilical
sampling. In the year following the guidance, 750 (67.8%) adequate samples were drawn
compared to 692 (62.2%) prior the guidance. This difference demonstrated significant
improvement (OR 1.28, 95% CI 1.07–1.52, P = 0.006) in umbilical vessel sampling. Following multivariate logistic regression,
inadequate sampling was associated with newborn weight below 2500 g (aOR 1.6, 95%
CI 1.2–2.1, p = 0.001), spontaneous vaginal delivery with a possible fetal metabolic
abnormality (aOR 2.2, 95% CI 1.7–2.7, p < 0.001), and vacuum deliveries (aOR 1.9,
95% CI 1.5–2.5, p < 0.001).
Conclusions
Guided training of proper umbilical blood sampling may reduce the rate of inadequate
postpartum blood gas results. Labor wards should consider carrying out annual demonstrations
of proper umbilical blood collection, with emphasis on factors that affect the quality
of the samplings.
Keywords
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Article info
Publication history
Published online: September 14, 2021
Accepted:
September 10,
2021
Received:
July 21,
2021
Footnotes
☆The study was conducted in Haifa, Israel.
Identification
Copyright
© 2021 Elsevier B.V. All rights reserved.
