Fetal anemia and heart rate patterns

Abstract

A retrospective survey was performed of the clinical records and cardiotocograms (CTG) of fetuses born in 1978 and 1979 at Helsinki University Central Hospital with hemoglobin concentration less than 170 g/liter in peripheral blood or umbilical artery. Eighty-three fetuses (0.7%) had thus defined anemia. Thirty-eight of them had late decelerations, 29 silent and nine sinusoidal fetal heart rate (FHR) patterns. Late decelerations and sinusoidal patterns were significantly more often associated with severe (hemoglobin concentration less than 80 g/liter) than with moderate anemia. The fetal outcome in terms of perinatal death and low APGAR scores after sinusoidal pattern was poorer than without this pattern, but the difference was not statistically significant. It is concluded that intermittent sinusoidal FHR pattern with late decelerations is suggestive of fetal anemia.

Sinusoidal Fetal Heart Rate Pattern

“…The sinusoidal pattern has been associated with fetal anemia in these cases of immunization. A sinusoidal pattern not associated with immunization has been described as coexisting with fetal hypoxia (2, 10, 8), fetomaternal erythrocyte passage, fetal anemia (15,21,25) and amnionitis (9). It has been regarded as a serious warning sign and, consequently, an antenatal sinusoidal heart rate pattern prior to intra-uterine fetal death (17, 8) has been reported.…”

Review article

“…Since the reports of normal outcomes in spite of SHR pattern, there has been a trend to suggest stricter definition in order to distinguish a "true" SHR uniformly associated with poor fetal outcome from a false pattern called "sinusoidal-like", "pseudosinusoidal", "presinusoidal", "sinus-like", or "sinusoidal simulating" that could be followed by a normal outcome [28,37,42,46,51]. NIJHUIS noted that "genuine" and "pseudo" SHR can be separated on the basis of absence or presence, of beat-to-beat variability [55].…”

“…KARINIEMI [42] reviewed 83 cases of neonatal anemia and found an obvious SHR in 9 fetuses and a suspicious one in 5 additional cases. This observation was confirmed by another group in Montreal [21].…”

Sinusoidal heart rate pattern: Reappraisal of its definition and clinical significance

“…It was postulated that since the SHR pattern disappeared during the exchange transfusion, tissue hypoxia of the central nervous system was the etiologic reason for the SHR pattern. During 1981–1982, there were several case reports as well as some systematic reviews of FHR patterns noted to be SHR pattern 28–40,41 . Similarly, cases related to fetal anemia, as the consequence of Rh isoimmunization or vasa previa, were interpreted as an ominous FHR pattern needing immediate evaluation and intervention.…”