RESUMO
The effect of a 50% increment or decrement in the recommended 5 ml/kg dose of a commercially available surfactant (Exosurf Neonatal) on the alveolar-arterial oxygen gradient was investigated in a multicenter, double-blind, placebo-controlled rescue trial conducted at 15 hospitals in the United States. Two doses of three different volumes (2.5, 5.0, and 7.5 ml/kg) were compared with two 5.0 ml/kg doses of air in 281 infants weighing > or = 1250 gm who had respiratory distress syndrome requiring mechanical ventilation and an arterial/alveolar oxygen ratio < 0.22. The first dose was given between 2 and 24 hours of age, and the second dose was given 12 hours later to all infants who still required mechanical ventilation. Infants were stratified at entry by gender and the magnitude of the arterial/alveolar oxygen ratio. The air placebo arm of the study was terminated early when reductions in mortality rates were proved in another rescue trial of this surfactant in infants with the same birth weights. For the first 48 hours, administration of a 2.5 ml/kg dose of surfactant provided less improvement in the alveolar-arterial oxygen gradient than doses of 5.0 and 7.5 ml/kg, which were equivalent. Similar results were observed in mean airway pressure (p < 0.05). There were no significant differences among the three dosage groups in mortality rate, air leak, bronchopulmonary dysplasia, and other complications of prematurity. There were no pulmonary hemorrhages in any group. Reflux of surfactant occurred more frequently in the 5.0 and 7.5 ml/kg groups. These results indicate that more sustained improvements in oxygenation are provided, with equal safety, by the standard two 5.0 ml/kg rescue doses of this surfactant than by the 2.5 ml/kg dose. No further benefit is gained from two larger doses given 12 hours apart.
Assuntos
1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Recém-Nascido Prematuro , Troca Gasosa Pulmonar/efeitos dos fármacos , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , 1,2-Dipalmitoilfosfatidilcolina/administração & dosagem , 1,2-Dipalmitoilfosfatidilcolina/farmacologia , 1,2-Dipalmitoilfosfatidilcolina/uso terapêutico , Peso ao Nascer , Pressão Sanguínea , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido de Baixo Peso/fisiologia , Recém-Nascido , Recém-Nascido Prematuro/fisiologia , Masculino , Oxigênio/sangue , Oxigenoterapia , Surfactantes Pulmonares/farmacologia , Surfactantes Pulmonares/uso terapêutico , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/mortalidade , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologiaRESUMO
In a multicenter, double-blind, placebo-controlled trial conducted at 23 hospitals in the United States, a single prophylactic 5 ml/kg dose of a synthetic surfactant (Exosurf Neonatal) or air placebo was administered shortly after birth to 215 infants with birth weights of 500 to 699 gm. Despite stratification at entry by birth weight and gender, by chance female infants predominated in the air placebo group and male infants predominated in the surfactant group. Among infants receiving synthetic surfactant, improvements in oxygen requirements were significant at 2 hours after birth (p = 0.014) and persisted for 3 days (p = 0.001); improvements in the alveolar-arterial partial pressure of oxygen gradient were significant at 6 hours after birth (p = 0.01) and persisted for 3 days (p = 0.008). Improvements in mean airway pressure were not significant at 2 or at 6 hours after birth (p = 0.622 and 0.083, respectively), but became significant thereafter and persisted for 3 days (p = 0.002). Pneumothorax was reduced by slightly more than half (25 vs 11; p = 0.014); death from respiratory distress syndrome (RDS) was also reduced (26 vs 15; p = 0.046). Overall neonatal mortality, however, was not significantly reduced (58 vs 46; p = 0.102). Other complications of RDS and prematurity were not altered, except that pulmonary hemorrhage occurred significantly more frequently in infants receiving synthetic surfactant (2 vs 12; p = 0.006). These findings indicate that a single prophylactic dose of synthetic surfactant in infants weighing 500 to 699 gm at birth improves lung function, incidence of air leak, and death from RDS but not overall mortality. The only safety problem identified was an increase in pulmonary hemorrhage.
Assuntos
Álcoois Graxos/uso terapêutico , Doenças do Prematuro/prevenção & controle , Fosforilcolina , Polietilenoglicóis/uso terapêutico , Surfactantes Pulmonares/uso terapêutico , Displasia Broncopulmonar/prevenção & controle , Hemorragia Cerebral/prevenção & controle , Método Duplo-Cego , Combinação de Medicamentos , Permeabilidade do Canal Arterial/prevenção & controle , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/mortalidade , Masculino , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Análise de SobrevidaAssuntos
Emulsões Gordurosas Intravenosas/metabolismo , Heparina/administração & dosagem , Recém-Nascido de Baixo Peso , Nutrição Parenteral Total , Nutrição Parenteral , Ácidos Graxos não Esterificados/sangue , Idade Gestacional , Heparina/farmacologia , Humanos , Recém-Nascido , Triglicerídeos/sangueAssuntos
Antiácidos/efeitos adversos , Doenças do Recém-Nascido/sangue , Magnésio/sangue , Antiácidos/administração & dosagem , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Recém-Nascido , Magnésio/efeitos adversos , Masculino , Tolazolina/efeitos adversosRESUMO
Serum parathyroid hormone and total and ionized Ca, Mg, and P levels were determined serially from birth to 96 hr of age in 28 infants of diabetic mothers (IDM, 15 Class A, 13 Class B, C, D) and their respective mothers at the time of delivery. In spite of marked decreases in concentrations of serum total and ionized Ca from birth to 24 to 48 hr, there was an insignificant increase in serum PTH values over this period in infants of insulin-dependent mothers. Infants of Class A diabetic mothers had an equivocal PTH response. Nineteen term control infants were similarly examined and had a significant increase in serum PTH postnatally. Relatively higher values of serum ionized Ca at birth in IDM were followed by greater decreases in ionized Ca from birth to 24-48 hr of age, and by decreased neonatal parathyroid function. The data support functional hypoparathyroidism as a basis for the hypocalcemia and hyperphosphatemia of IDM. It is speculated that increased concentrations of serum ionized Ca in utero and suppression of activity in the fetal parathyroid glands may be a cause for the functional hypoparathyroidism.