Correlation of Fetal Heart Rate Patterns with Umbilical Artery pH and Catecholamines During Last Hour of Labor

Abstract

Fetal heart rate (FHR) patterns were analysed during last hour of labour and correlated to umbilical artery pH and catecholamine (CA) levels. Fetuses with pathological FHR had significantly higher levels of CA than those with normal FHR. Particulary high levels were found in fetuses with bradycardia and late decelerations. FHR was further analysed by a computer (DPAC, data processor and computer) in 100 women during last hour of labor. No correlation between deceleration areas of variability and umbilical artery pH and CA was found. It is concluded that although there is a good correlation between the general FHR-pattern and umbilical artery CA and pH it is impossible to quantify the degree of fetal distress by calculation of deceleration areas and variability.

Catecholamines in arterial and venous umbilical blood: placental extraction, correlation with fetal hypoxia, and transcutaneous partial oxygen tension

“…There was a significant inverse relation with NE concentrations rising as tcpO 2 values decreased. No correlation could be detected between arterial E levels and the tcpO 2 .…”

“…Various investigators have by HUGH [14] for intrapartum fetal monitoring reported that analogous correlations exist between are contradictory. Some authors reported good catecholamines, acid-base balance [2,10,18,20], agreement between fetal arterial and transand the APGAR score [18,25]. The results on cutaneous pO 2 levels [11].…”

“…tachycardia may reflect a circulatory compensation for acute changes in the blood oxygen con- 2 , and tachycardia) and hypoxic acidosis/postpartum transcutaneous-arterial pO 2 difference: The results depression are associated with increased arterial obtained on measurement of the tcpO 2 as described NE concentration. Various investigators have by HUGH [14] for intrapartum fetal monitoring reported that analogous correlations exist between are contradictory.…”

“…Investigations performed in animal experiments [6,7,16,17,19] as well as in man [2,3,9,10,18,20,25] suggest that fetal hypoxia is associated with an increase in circulating catecholamines due to sympathoadrenal stimulation. The correlation between catecholamines and cardiovascular, respiratory, and metabolic changes as determined during intrapartum fetal monitoring by means of cardiotocography (CTG), fetal blood gas analysis, and measurement of the transcutaneous partial oxygen tension (tcpC^) has not yet been exhaustively investigated.…”

“…These gaps in our knowledge are attributable to some extent to methodological factors. The older (fluorimetric) tests, which require blood volumes of 15-20ml, are restricted to the detection of epinephrine (E) and norepinephrine (NE) in mixed cord blood [3,22] or venous umbilical blood [18,23], and some studies only measured total catecholamines [2,20] without further differentiation. In contrast, the radioenzymatic single-isotope technique [8,29] allows the specific measurement of E, NE and the third catecholamine, dopamine (D), in 0.1-0.2 ml plasma.…”