RESUMO
In an investigation of the effects of intrauterine, intravascular transfusions (IUT) on fetal and neonatal hemolysis and erythropoiesis, 12 fetuses who received IUT for treatment of severe isoimmunization had serial measurements of hemoglobin concentration, Kleihauer-Betke stains to detect fetal hemoglobin-containing erythrocytes, and determination of plasma erythropoietin (EPO) concentration before each IUT, at birth, and postnatally. Reticulocyte counts and sensitizing antibody titers were measured in five fetuses. Mean values before the first IUT, before the final IUT, and at birth were as follows: hemoglobin level, 6.1, 9.1, and 11.3 gm/dl; reticulocyte count, 22.7%, 0.5%, and 0.9%; fetal hemoglobin-containing erythrocytes, 100%, 1.6%, and 1.5%; and EPO level, 12, 56, and 756 mU/ml, respectively. Only one neonate required exchange transfusion. In the first month postnatally, all infants had a profound anemia. All but one infant required simple blood transfusions postnatally. Before the first postnatal transfusion, mean hemoglobin concentration was 6.2 gm/dl, mean reticulocyte count was 0.8%, mean erythropoietin concentration was 23 mU/ml, and the sensitizing antibody titer remained markedly elevated. Except for the surge of EPO at birth, EPO levels did not rise prenatally or postnatally unless marked anemia (hemoglobin level less than 5 gm/dl) occurred. These observations suggest that the intrauterine and postnatal anemia in fetuses who receive IUTs may be explained both by hemolysis of newly formed erythrocytes by circulating antibody, which typically persisted for more than a month after birth, and by suppressed erythropoiesis.
Assuntos
Transfusão de Sangue Intrauterina/métodos , Eritropoese , Hemólise , Isoimunização Rh/terapia , Anemia Neonatal/terapia , Peso ao Nascer , Contagem de Células Sanguíneas , Transfusão de Sangue , Idade Gestacional , Hematócrito , Hemoglobinas , Humanos , Recém-NascidoRESUMO
This study was undertaken to determine the factors that are important in determining the erythropoietin response in low-birth-weight infants during the period of so-called anemia of prematurity. In the first weeks of life oxygen consumption in a group of 21 infants gradually increased as hemoglobin level fell. The magnitude of the erythropoietin response inversely varied with the central venous oxygen tension (P-vO2) (r = -0.55, P less than 0.001). When the P-vO2 declined to less than 30 torr, erythropoietin values were uniformly increased above the "normal" range (defined as the values associated with P-vO2 greater than 38 torr). Erythropoietin values varied inversely with hemoglobin but in general did not exceed the values observed for normal adult men. The erythropoietin values in the infants were remarkably lower at any given hemoglobin level when compared with those of older children with anemia resulting from bone marrow failure. In general, elevations of erythropoietin were seen when the hemoglobin concentration declined to less than 10.0 gm/dl. Change in heart rate did not appear to be a reliable indicator of the presence of anemia; rather, it correlated best with oxygen consumption.
Assuntos
Anemia/sangue , Eritropoetina/biossíntese , Doenças do Prematuro/sangue , Adulto , Anemia/fisiopatologia , Anemia/terapia , Pressão Venosa Central , Eritropoetina/sangue , Frequência Cardíaca , Hemoglobinas/análise , Humanos , Recém-Nascido , Doenças do Prematuro/fisiopatologia , Doenças do Prematuro/terapia , Masculino , Consumo de OxigênioAssuntos
Agranulocitose/tratamento farmacológico , Lítio/uso terapêutico , Neutropenia/tratamento farmacológico , Criança , Pré-Escolar , Doença Crônica , Ensaio de Unidades Formadoras de Colônias , Feminino , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Lactente , Contagem de Leucócitos , Carbonato de Lítio , MasculinoRESUMO
We evaluated the use of dexamethasone in the management of acute laryngotracheobronchitis (croup). Thirty patients, ranging in age from eight to 60 months, were evaluated in a prospective, double-blind study. Patients received dexamethasone, 0.3 mg/kg at the time of admission and a similar dose 2 hours later, and were compared with a placebo group receiving saline. Sixteen patients received dexamethasone and 14 patients received the placebo. Severity of each group was scored by a standardized system. Patients receiving dexamethasone had a mean admission score of 8.46 points; patients receiving placebo, 8.14. Twenty-four hours after admission the patients in the treatment group had a mean score of 1.19 as contrasted with a score of 5.58 for the placebo group (P less than 0.01). We concluded that dexamethasone when administered in adequate dosage by an intramuscular route hastens the recovery of infants and children with acute uncomplicated croup.