BJOG. 2011 Sep;118(10):1239-1246. doi: 10.1111/j.1471-0528.2011.03027.x. Epub 2011 Jun 14.
Fetal blood sampling in addition to intrapartum ST-analysis of the fetal electrocardiogram: evaluation of the recommendations in the Dutch STAN® trial.
Becker J, Westerhuis M, Sterrenburg K, van den Akker E, van Beek E, Bolte A, van Dessel T, Drogtrop A, van Geijn H, Graziosi G, van Lith J, Mol B, Moons K, Nijhuis J, Oei S, Oosterbaan H, Porath M, Rijnders R, Schuitemaker N, Wijnberger L, Willekes C, Visser G, Kwee A.
Department of Obstetrics and Gynaecology, University Medical Centre Utrecht, Utrecht Department of Obstetrics and Gynaecology, Onze Lieve Vrouwe Gasthuis, Amsterdam Department of Obstetrics and Gynaecology, St Antonius Hospital, Nieuwegein Department of Obstetrics and Gynaecology, Free University Medical Centre, Amsterdam Department of Obstetrics and Gynaecology, TweeSteden Hospital, Tilburg Department of Obstetrics and Gynaecology, Leiden University Medical Centre, Leiden Department of Obstetrics and Gynaecology, Amsterdam Medical Centre, Amsterdam department of Epidemiology, Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht Department of Obstetrics and Gynaecology, Maastricht University Medical Centre, Maastricht Department of Obstetrics and Gynaecology, Máxima Medical Centre, Veldhoven Department of Obstetrics and Gynaecology, Jeroen Bosch Hospital, ‘s Hertogenbosch Department of Obstetrics and Gynaecology, Diakonnesenhuis, Utrecht, the Netherlands.
Abstract
Objectives: To evaluate the recommendations for additional fetal blood sampling (FBS) when using ST-analysis of the fetal electrocardiogram. Design Prospective cohort study. Setting Three academic and six non-academic teaching hospitals in the Netherlands. Population Labouring women with a high-risk singleton pregnancy in cephalic position beyond 36 weeks of gestation. Methods: In labouring women allocated to the STAN® arm of a previously published
randomised controlled trial who underwent one or more FBS during delivery, we assessed whether FBS was performed according to the trial protocol and how fetal acidosis, defined as an FBS pH < 7.20, was related to ST-waveform analysis. Main outcome measures The number of FBS showing fetal acidosis, related to the different STAN® criteria where additional FBS is recommended. Results: Among 2827 women monitored with STAN® , 297 underwent FBS, of whom 171 (57.6%) were performed according to the predefined criteria and 126 were performed in absence of these criteria. In the first group, rates of fetal acidosis (pH < 7.20) were two of 18, none of nine, 12 of 111 and three of 33 when FBS was taken for abnormal cardiotocogram (CTG) at the start, intermediary CTG at the start, abnormal CTG >60 minutes, and poor electrocardiogram quality, respectively. When the predefined criteria were not met and ST-analysis showed no ST-events, only two incidents of fetal acidosis were seen. Conclusions: The performance of FBS is valuable in the advised STAN® criteria. When these criteria are not met, performance of FBS does not seem helpful in the detection of fetal acidosis.
