Obstet Gynecol Sci.  2020 Apr;63(3):293-304. 10.5468/ogs.2020.63.3.293.

Umbilical cord arterial blood gas analysis in term singleton pregnancies: a retrospective analysis over 11 years

• Lee JH
• Jung J
• Park H
• Kim Sy
• Kwon Dy
• Choi SJ
• Oh Sy
• Roh CR

• KMID: 2500419
• DOI: http://doi.org/10.5468/ogs.2020.63.3.293

Abstract

Objective
Given that the large volume of data on cord arterial blood gas analysis (ABGA) have been rarely addressed in Korean population, we aimed to examine the incidence, associated factors, and neonatal outcomes in cases of low cord pH, and investigate the incidence of cerebral palsy (CP).
Methods
From data of all consecutive term singleton pregnancies delivered in our institution from 2006 to 2016 (n=15,701), cases with cord ABGA (n=14,221) available were included. We collected information on maternal clinical characteristics and delivery outcomes and also examined neonatal and infant outcomes, including neonatal intensive care unit (NICU) admission and CP, in cases with low cord pH, defined as a pH <7.1.
Results
Rates of low Apgar scores at 1 minute (<4) and 5 minutes (<7) were 0.6% (n=79) and 0.4% (n=58), respectively. Rates of cord pH <7.2, <7.1, and <7.0 were 7.1% (n=1,011), 1.1% (n=163), and 0.3% (n=38), respectively. Among cases with low cord pH, 30.1% (n=49/163) were admitted to the NICU and 11.0% (n=18/163) required ventilator support. Ultrasonography of the brain was performed in 28.8% (n=47/163), with abnormal findings observed in 27.7% (n=13/47). Among cases with low cord pH, 1.8% (n=3/163) were subsequently diagnosed with CP, including 2 cases of spastic CP and 1 of ataxic CP.
Conclusion
Although low cord pH was a relatively frequent finding observed in 1 out of every 87 cases, hypoxic-ischemic encephalopathy-related CP was found in only 1 out of 7,111 term singleton deliveries over 11 years in our institution.

Keyword

Umbilical cord; Analysis, blood gas; Term birth; Cerebral palsy

Figure

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  Fig. 1 Study population with inclusion and exclusion criteria.FDIU, Fetal death in utero; ABGA, arterial blood gas analysis; VBGA, venous blood gas analysis.

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  Fig. 2 Clinical course and information in cases with low cord blood pH.NICU, neonatal intensive care unit; USG, ultrasonography; MRI, magnetic resonance imaging.

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