Estudo comparativo da predição da anemia em fetos transfundidos pelos métodos do índice cardiofemoral e pico da velocidade sistólica da artéria cerebral média

Abstract

Introduction: Despite the great progress achieved to date with the prevention, diagnosis and treatment, isoimmunization Rhesus (Rh) is still the leading cause of severe anemia in fetuses, generating significant morbidity and mortality. The diagnostic criteria for fetal anemia are key for indicating the best approach in the monitoring and treatment of pregnancies complicated by Rh isoimmunization. Currently, the Center for Fetal Medicine, Hospital das Clinicas, Federal University of Minas Gerais (CEMEFE-HC-UFMG) uses the measurement of peak systolic velocity of the middle cerebral artery associated with cardiofemoral index (ICF) for the evaluation of fetuses of pregnant women affected and need to perform cordocentesis for hematimetria. The knowledge of the behavior of these indices in fetuses at risk for anemia is already well known, but not yet known whether these tests behave similarly in fetuses multitransfused and if the hemoglobin level in the fetal circulation of adult prejudice the outcome of these . Objectives: The study aims to assess the accuracy of critical cardiofemoral index and peak systolic velocity in the middle cerebral artery in fetuses undergoing intrauterine transfusions and subsequent identify the most reliable parameter for the diagnosis of severe anemia. Patients and methods: We analyzed 23 pregnant women undergoing intrauterine transfusions at least three (TIU). The data of the first three TIUs were divided into three groups regarding: first, second and third TIU. Patients were followed during pregnancy and undergo noninvasive tests to measure the ICF and peak systolic velocity of the middle cerebral artery (MCA-PSV) for the detection of severe fetal anemia from 22 weeks of gestation. If there were signs of fetal hydrops or alteration of a non-invasive, the patient was subjected to cordocentesis and study of fetal red blood cells. The data relating to ICF and PVS-ACM were compared to the results of pre-transfusion hemoglobin obtained by cordocentesis and assigned to their respective groups. Results: The sensitivity of ICF in the first, second and third TIU was respectively 80%, 75% and 90%. Results from negative predictive value (NPV) were 90%, 85% and 89%, respectively. The sensitivity of the PVS-ACM in the first, second and third TIU was respectively 80%, 75% and 45%. The results VPN were 88.8%, 80% and 60%, respectively. The receiver operating characteristic curves (ROC) for the ICF in the first, second and third TIU showed areas under the curves, respectively, 0.683 (95% CI, 0.384 to 0.983), 0.746 (95% CI, 0.510 to 0.982) and 0.913 (95% CI, 0.792 to 1.0). The accuracy of the ICF and PVS-MA was tested in combination in the three groups, with a sensitivity of 64%, 57% and 40% when tested in series, respectively, and 96%, 93% and 95% when tested in parallel, respectively. Conclusions: The index cardiofemoral presents itself as a diagnostic tool for severe fetal anemia good accuracy while maintaining its effectiveness even in fetuses multitransfused. The PVS-ACM loses value after repeated intrauterine transfusions. The use of PVSACM in association with the ICF increases the sensitivity of the screening of severe fetal anemia.