Predictive factors of perinatal mortality in transfused fetuses due to maternal alloimmunization: what really matters?

INTRODUCTION: Alloimmunization is the main cause of fetal anemia. There are not many consistent analyses associating antenatal parameters to perinatal mortality in transfused fetuses due to maternal alloimmunization. The study aimed to determine the prognostic variables related to perinatal death. MATERIAL AND METHODS: A cohort study analyzed 128 fetuses treated with intrauterine transfusion (IUT), until the early neonatal period. Perinatal mortality was associated with prognostic conditions related to prematurity, severity of fetal anemia and IUT procedure by univariated logistic regression. Multiple logistic regression was used to compute the odds ratio (OR) for adjusting the hemoglobin deficit at the last IUT, gestational age at birth, complications of IUT, antenatal corticosteroid and hydrops. RESULTS: Perinatal mortality rate found in this study was 18.1%. The hemoglobin deficit at the last IUT (OR: 1.26, 95% CI: 1.04-1.53), gestational age at birth (OR: 0.53, 95% CI: 0.38-0.74) and the presence of transfusional complications (OR: 5.43, 95% CI: 142-20.76) were significant in predicting fetal death. CONCLUSION: Perinatal mortality prediction in transfused fetuses is not associated only to severity of anemia, but also to the risks of IUT and prematurity.

Correlação entre medidas ultra-sonográficas do coração e o deficit de hemoglobina em fetos de gestantes aloimunizadas / Correlation between echographic cardiac measurements and hemoglobin deficit in fetus of red cell alloimmunized pregnancies

OBJETIVO: verificar a correlação entre as medidas ultra-sonográficas do coração fetal e o deficit de hemoglobina em fetos de gestantes aloimunizadas. MÉTODOS: estudo transversal, no qual foram incluídos 60 fetos de 56 mulheres aloimunizadas, com idade gestacional entre 21 e 35 semanas. Foram realizados 139 procedimentos. Antes da cordocentese para a coleta de sangue fetal, as medidas cardíacas e o comprimento do fêmur (CF) foram avaliados pela ultra-sonografia. O diâmetro biventricular externo (DBVE) foi obtido no final da diástole, com o cursor modo-M perpendicular ao septo interventricular, nas válvulas atrioventriculares, medindo-se a distância entre as partes externas dos epicárdios. A medida do diâmetro atrioventricular (DAV) foi obtida posicionando-se o mesmo cursor ao longo do septo interventricular, avaliando-se a distância entre a base e o ápice do coração. O CF foi determinado do trocanter maior à metáfise distal. Foi calculada a circunferência cardíaca (CC). Para ajustar as medidas cardíacas à idade gestacional, dividiu-se cada uma dessas medidas pela medida do CF. A concentração de hemoglobina foi determinada por espectrofotometria no sistema Hemocue®. O deficit de hemoglobina foi calculado baseado na curva de normalidade de Nicolaides. RESULTADOS: observaram-se correlações diretas e significativas entre as medidas cardíacas avaliadas e o deficit de hemoglobina. Para a predição das anemias moderada e grave, a sensibilidade e a especificidade encontradas foram, respectivamente, de 71,7 e 66,3 por cento para a razão DBVE e CF; 65,8 e 62,4 por cento para a DAV e CF e 73,7 e 60,4 por cento para a CC e CF. CONCLUSÕES: nos fetos de gestantes aloimunizadas, as medidas cardíacas ultra-sonográficas avaliadas correlacionam-se diretamente com o deficit de hemoglobina.

PURPOSE: to verify the correlation between ultrasonography heart measures and hemoglobin deficit in fetuses of alloimmunized pregnant women. METHODS: a transversal study, including 60 fetuses, with 21 to 35 weeks of gestational age, from 56 isoimmunized pregnant women. A number of 139 procedures were performed. Before cordocentesis for the collection of fetal blood, cardiac measures and femur length (FL) were assessed by ultrasonography. The external biventricular diameter (EBVD) was obtained by measuring the distance between the epicardic external parts at the end of the diastole, with the M-mode cursor perpendicular to the interventricular septum, in the atrioventricular valves. The measure of the atrioventricular diameter (AVD) was obtained by positioning the same cursor along the interventricular septum, evaluating the distance between the heart basis and apex. The FL was determined from the trochanter major to the distal metaphysis. The cardiac circumference (CC) was also calculated. To adjust the cardiac measure to the gestational age, each of these measures were divided by the FL measure. Hemoglobin concentration has been determined by spectrophotometry with the Hemocue® system. Hemoglobin deficit calculation was based in the Nicolaides's normality curve. RESULTS: direct and significant correlations were observed between the cardiac measures evaluated and the hemoglobin deficit. To predict moderate and severe anemia, the sensitivity and specificity found were 71.7 and 66.3 percent for EBVD and FL, 65.8 and 62.4 percent for AVD and FL, and 73.7 and 60.4 percent for CC and FL, respectively. CONCLUSIONS: ultrasonography cardiac measures assessed from fetuses of isoimmunized pregnant women correlate directly with hemoglobin deficit.

[Correlation between echographic cardiac measurements and hemoglobin deficit in fetus of red cell alloimmunized pregnancies]. / Correlação entre medidas ultra-sonográficas do coração e o deficit de hemoglobina em fetos de gestantes aloimunizadas.

PURPOSE: to verify the correlation between ultrasonography heart measures and hemoglobin deficit in fetuses of alloimmunized pregnant women. METHODS: a transversal study, including 60 fetuses, with 21 to 35 weeks of gestational age, from 56 isoimmunized pregnant women. A number of 139 procedures were performed. Before cordocentesis for the collection of fetal blood, cardiac measures and femur length (FL) were assessed by ultrasonography. The external biventricular diameter (EBVD) was obtained by measuring the distance between the epicardic external parts at the end of the diastole, with the M-mode cursor perpendicular to the interventricular septum, in the atrioventricular valves. The measure of the atrioventricular diameter (AVD) was obtained by positioning the same cursor along the interventricular septum, evaluating the distance between the heart basis and apex. The FL was determined from the trochanter major to the distal metaphysis. The cardiac circumference (CC) was also calculated. To adjust the cardiac measure to the gestational age, each of these measures were divided by the FL measure. Hemoglobin concentration has been determined by spectrophotometry with the Hemocue system. Hemoglobin deficit calculation was based in the Nicolaides's normality curve. RESULTS: direct and significant correlations were observed between the cardiac measures evaluated and the hemoglobin deficit. To predict moderate and severe anemia, the sensitivity and specificity found were 71.7 and 66.3% for EBVD and FL, 65.8 and 62.4% for AVD and FL, and 73.7 and 60.4% for CC and FL, respectively. CONCLUSIONS: ultrasonography cardiac measures assessed from fetuses of isoimmunized pregnant women correlate directly with hemoglobin deficit.