Methodology and Clinical Value of Transcutaneous Blood Gas Measurements in the Fetus

Abstract

SummaryAiming at an improvement of fetal surveillance in high risk cases, a clinical trial was performed to evaluate the potential of fetal tcPco^ monitoring. An electrochemical tcPco 2 sensor heated at 44 ° C was applied in 119 fetuses after abnormal heart rate patterns had occured. The number of operative deliveries for fetal distress was reduced to 14 cases by means of the biochemical parameters (tcPco ~ )ar >d fetal blood analysis (FBA). In the majority of cases with pathologic heart rate patterns the tcPco 2 values were prepathologic or normal (60 %), while in 68 % of cases with prepathologic heart rate patterns the tcPco _ level was normal. At all instances an intrauterine complication was indicated by a marked rise of the tcPco2 level. The clinical benefit of using the tcPco measurement is the better specificity of detecting fetal distress when compared with the use of cardiotocography alone. Furthermore the tcPco technique has the advantage of providing continuous information about one biochemical parameter and of avoiding the necess ity of repeated incisions of the scalp, as compared with the technique of fetal blood analysis. In conclusion the use of this non-traumatic technique lends itself to avoid unnecessary operative deliveries in high risk cases.

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