The impact of nuchal cord on umbilical cord blood gas analysis and ischaemia-modified albumin levels in elective C-section.

This study was designed to evaluate umbilical cord ischaemia-modified albumin (IMA) levels and the cord blood gas parameters of foetuses with or without nuchal cords, at the time of elective C-section. The cross-sectional study population consisted of the patients who were admitted to the Tertiary Care Center between February and June 2015. Women with uncomplicated single term gestations between 37 and 40 completed weeks and scheduled for elective C-sections were included in the study. Fifty cases with a nuchal cord and 50 cases without a nuchal cord were recruited. Nuchal cord blood gas analysis and the IMA levels were evaluated. The IMA levels in umbilical artery of foetuses both in the study and control groups were similar (0.714 ± 0.150 vs. 0.689 ± 0.107 ABSU, p = .340, respectively). The umbilical artery pH values of the study group were significantly lower than that in the control group (7.31 ± 0.04 vs. 7.32 ± 0.03, p = .042; respectively). The results of the current study indicate that the nuchal cord has an impact on the foetal cord blood gas parameters to some extent before the initiation of labour. Fortunately, this impact does not end up with foetal tissue ischaemia, as confirmed by the IMA levels. Impact statement What is already known on this subject? The impact of nuchal cord on perinatal outcomes has been the subject of research for many years. Although the accumulated data has pointed out some unfavourable perinatal effects, the heterogeneity of the study groups both including a vaginal delivery and C-section and the inability to adjust the interfering factors ended up with some controversies. This is why there is not much known about the effects of the nuchal cord in women who are not in the labour process. What do the results of this study add? The current study aimed to exclude the interfering effects such as the active stage of labour. In this study, elective caesarean sections were selected as the study population to evaluate the effects of the nuchal cord on cord blood gas parameters and the IMA values. pH analysis in cord blood is used to detect hypoxia and the IMA is a new ischaemia marker. The results revealed that the in utero nuchal cord is associated with a significantly higher pCO2 and lower pH values and similar IMA values. What are the implications of these findings for clinical practice and/or further research? The final outcome supports that the nuchal cord causes alterations in cord blood gas analysis but this does not reach critical levels. Therefore, the results show that there is no need to change clinical practice when the nuchal cord is detected by ultrasound in a term gestation.

IL-6 and TNFalpha across the umbilical circulation in term pregnancies: relationship with labour events.

OBJECTIVE: We have determined venous and arterial cord blood levels for IL-6 and TNFalpha at the time of delivery to assess gestational tissue versus fetal sources in labouring and non-labouring patients at term, and the relationship to labour events. METHODS: Fifty-five patients were studied (elective cesarean section n=24, and labouring n=31) with blood sampling from a clamped segment of cord after delivery of the fetus and from the cord at its insertion into the placenta after delivery of the placenta, with subsequent measurement of blood gases, pH, IL-6 and TNFalpha. RESULTS: Umbilical cord levels for IL-6 were increased by 4 fold in low risk labouring patients, and a further 6 fold when showing histologic chorioamnionitis, but with no evident effect of nuchal cord with 'variable' fetal heart rate decelerations, fetal acidemia, nor of labour duration. IL-6 levels from the cord at its insertion into the placenta were generally higher than those from the respective umbilical levels indicating that placental release of IL-6 into cord blood must be occurring. However, a consistent venoarterial difference for IL-6 and thereby a net flux from the placenta could not be demonstrated. TNFalpha levels for both patient groups were uniformly low for all of the cord measurements with no significant differences noted. CONCLUSION: Umbilical cord levels for IL-6 are increased in low risk labouring patients at term in the absence of evident infection which likely involves both gestational tissue and fetal contributions. Cord levels for IL-6 are further increased in low risk labouring patients showing histologic chorioamnionitis which might then contribute to newborn morbidity in these pregnancies.