Revista Matronas

Revista Matronas

ABRIL 2018 N° 1 Volumen 6

Arterial blood gas results variability in umbilical cord blood according to the time elapsed until test

Section: Originales


1 Patricia Guillén Guzmán, 1 Noelia Carmen Planells Domingo, 2 Silvia Navarro Hernández, 2 Sonia Carratalá Navarro, 3 Juan Antonio Torres Martínez


1 EIR 1er Hospital Lluís Alcanyis, Xàtiva2 EIR 2º Hospital Lluís Alcanyis, Xàtiva3 Matrón Área de Xàtiva, Ontinyent

Contact email: paguiguz@hotmail.com


Purpose: in the present study, the main aim was to detect potential differences in arterial blood gas results in umbilical cord blood samples drawn at one, 10, or 30 minutes, in the same room conditions.
Methods: a prospective cross-sectional observational study was conducted in pregnant women in the Department of Health of Xàtiva-Ontinyent (Valencian Autonomous Community, Spain). The study subjects were full-term pregnant women with a single pregnancy who were admitted to the delivery area of the Lluís Alcanyís Hospital (Xàtiva) from November 1, 2016 to April 1, 2017. Once the women who met all the inclusion criteria had been selected, at the time of birth and after delivery, an arterial blood sample was taken from the cord in the first seconds, trying to obtain a correct specimen. Samples were tested within the first minute after extraction, and at 10 and 30 minutes after extraction, in the same room conditions in the delivery room. All data were recorded in a dedicated worksheet for later analysis using the statistical software package SPSS 20.
Results: as the comparison of arterial blood gas data did not always show statistical significance, correlations with other variables only included, besides time elapsed before tests, the fact of the cord having been clamped or not when the sample was drawn. The results of a comparative analysis of values according to time elapsed before measurements were based on Student’s t tests and Wilcoxon test and showed: CO2 was not significant at any test time; pH was only significant from minute 1 to minute 10 (p= 0.006); EB change was significant at all times; a significant change occurs in O2 between 10-30 minutes (p= 0.021) and between 30-1 (p= 0.003); thus, it is significant from minute 10 onwards. When comparing clamping (yes/no), only EB group 1-10 minute achieves significance (p= 0.026). However, in the analysis of temporal change, significance is established for the group of "no clamping".
Conclusions: it is recommended to perform sample tests within the first 10 minutes after extraction and after umbilical cord clamping.


rterial blood gas test; umbilical cord; fetal blood; labor

Versión en Español


Variabilidad de la gasometría arterial de cordón umbilical según el tiempo transcurrido antes de su análisis

Artículo completo no disponible en este idioma / Full article is not available in this language


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