The effect of fetal hydrops on the rate of fall of hemoglobin after fetal intravascular transfusion for red cell alloimmunization.
OBJECTIVE
We aimed to assess whether there is a difference between hydropic and nonhydropic fetuses in the rate of fall of hemoglobin (Hb) following intravascular transfusions.


METHODS
Eighty-three intravascular transfusions in 34 fetuses were analyzed. The pretransfusion and posttransfusion Hb values, the gestational age, the volume of blood transfused, the number of days between transfusions and the rate of fall of Hb per day following a transfusion were assessed. Hb levels were expressed as multiples of standard deviation from the normal mean for gestational age.


RESULTS
Eleven fetuses were hydropic at presentation and 23 were not. Twenty-three transfusions were undertaken in the 11 fetuses while they were hydropic and 60 transfusions were performed in nonhydropic fetuses. Comparisons of transfusion variables between the two groups were performed both for the first transfusion only and also for the total number of transfusions. The rate of Hb fall per day following a transfusion was similar in the two groups on both comparisons. The posttransfusion Hb level tended to be lower and the intervals between transfusions were a little shorter in the hydropic group, but these differences were not statistically significant.


CONCLUSIONS
The posttransfusion Hb tended to be lower in the hydropic fetuses, but the fall in Hb was not faster in these cases. Therefore, with a similar rate of daily Hb decline in both groups, the hydropic fetuses are expected to become anemic again sooner than the nonhydropic fetuses only because of the lower posttransfusion Hb. The timing of the next transfusion should therefore be based on the posttransfusion Hb and the normal predicted drop per day irrespective of the presence or absence of hydrops.
Abdel-Fattah
S A
SA
Fetal Medicine Research Unit, University of Bristol, St. Michael's Hospital, Bristol, UK.
Carroll
S G
SG
Kyle
P M
PM
Soothill
P W
PW
D001803:Blood Transfusion; D001805:Blood Transfusion, Intrauterine / Q000379:methods; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D005319:Fetal Hemoglobin / Q000378:metabolism*; D006801:Humans; D015160:Hydrops Fetalis / Q000097:blood*; D011247:Pregnancy; D018709:Statistics, Nonparametric
D005319:Fetal Hemoglobin