RESUMO
Elevated blood lactate levels that declined to normal after erythrocyte transfusion were observed in 17 of 37 otherwise healthy infants with anemia of prematurity (26.1 +/- 2.1 mg/dl vs 12.3 +/- 0.9 mg/dl; p < 0.001). Posttransfusion heart rate in this group decreased from 155 +/- 1 beats/min to 150 +/- 2 beats/min (p = 0.01). Blood lactate concentration may be a predictor of the need for transfusion in anemia of prematurity.
Assuntos
Anemia Neonatal/terapia , Transfusão de Componentes Sanguíneos , Doenças do Prematuro/terapia , Lactatos/sangue , Anemia Neonatal/sangue , Anemia Neonatal/epidemiologia , Frequência Cardíaca/fisiologia , Hematócrito , Humanos , Lactente , Recém-Nascido , Doenças do Prematuro/sangue , Ácido Láctico , Estudos ProspectivosRESUMO
This study was undertaken after the observation in a premature infant of a hemolytic anemia with Heinz bodies that appeared to result from administration of a multivitamin preparation. In vitro incubation of erythrocytes of premature infants with sodium ascorbate (0.1 mg/ml) for 3 hours significantly raised the number of Heinz body-containing cells from 17.6 +/- 5.7% to 27.2 +/- 8.2% (mean +/- SE). Erythrocytes of term infants and those of adults developed Heinz bodies after exposure to higher sodium ascorbate concentrations (1.0 mg/ml). Erythrocytes of adult and newborn guinea pigs were similarly affected by sodium ascorbate. Daily intraperitoneal injections of 500 mg of sodium ascorbate, given for 7 days to four adult guinea pigs, caused significant Heinz body formation. These studies indicate that the erythrocytes of premature infants are uniquely sensitive to the development of Heinz bodies after exposure to sodium ascorbate. The levels required to produce Heinz bodies in vitro are in the range of those found in vivo after routine administration of vitamin C to premature infants. The significance of these observations in the development of hyperbilirubinemia in premature infants and in the safety of vitamin C remains to be determined.
Assuntos
Anemia Hemolítica/induzido quimicamente , Ácido Ascórbico/efeitos adversos , Eritrócitos/efeitos dos fármacos , Doenças do Prematuro/sangue , Adulto , Anemia Hemolítica/patologia , Animais , Eritrócitos Anormais/patologia , Feminino , Cobaias , Corpos de Heinz/efeitos dos fármacos , Humanos , Recém-Nascido de Baixo Peso/sangue , Recém-Nascido , Doenças do Prematuro/induzido quimicamenteAssuntos
Trombocitopenia/tratamento farmacológico , gama-Globulinas/administração & dosagem , Feminino , Humanos , Recém-Nascido , Infusões Intravenosas , Troca Materno-Fetal , Metilprednisolona/administração & dosagem , Prednisona/administração & dosagem , Gravidez , Complicações Hematológicas na Gravidez , Trombocitopenia/etiologiaRESUMO
The association between platelet counts and mechanical ventilation was assessed in 61 newborn infants with respiratory distress syndrome, 10 infants with congenital diaphragmatic hernia, and 10 infants with tracheoesophageal fistula. A significant decrease in platelet counts was observed during mechanical ventilation: (mean +/- SD) reduction of 39% +/- 5%, 42% +/- 5.6%, and 11.9% +/- 5.4% in the three groups, respectively, independent of other causes. In the group with congenital diaphragmatic hernia, there was a significant correlation between mean airway pressure and the reduction in platelet counts. In a subsequent series of experiments, platelet counts were recorded before and during ventilation in rabbits. A significant mean decrease of 37.3% in platelet counts was associated with ventilation with either air or pure oxygen. Results of these studies indicate that mechanical ventilation itself may cause a major decrease in platelet count in newborn infants.