RESUMO
In a multicenter, double-blind, placebo-controlled rescue trial conducted at 13 Canadian hospitals, two 5 ml/kg doses of a synthetic surfactant or air placebo were administered to 344 infants with birth weights of 750 to 1249 gm who had established respiratory distress syndrome and an arterial/alveolar oxygen tension ratio less than 0.22. The first dose was given between 2 and 24 hours of age, and the second dose was given 12 hours later to the infants remaining on mechanical ventilation. Infants were stratified at study entry by birth weight and gender. The trial was terminated short of the targeted sample size because significant reductions in mortality were observed in another rescue trial completed in the United States in the same weight class of infants. Despite premature termination of the trial, the rate of survival without bronchopulmonary dysplasia was increased (61% vs 52%; p = 0.046) in infants treated with surfactant. In addition, there was a significant reduction in the incidence of overall pulmonary air leak (46% vs 32%; p = 0.009), pneumothorax (27% vs 17%; p = 0.023), and pulmonary interstitial emphysema (40% vs 28%; p = 0.018) in infants treated with synthetic surfactant. There was no difference in the incidence of bronchopulmonary dysplasia, apnea, or pulmonary hemorrhage. Significant improvements in alveolar-arterial oxygen tension gradient, arterial/alveolar oxygen tension ratio, and oxygen and ventilator requirements through day 7 were present. These findings indicate that rescue therapy with synthetic surfactant can improve outcome for premature infants weighing 750 to 1249 gm with respiratory distress syndrome.
Assuntos
Álcoois Graxos/administração & dosagem , Fosforilcolina , Polietilenoglicóis/administração & dosagem , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Ar , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Recém-Nascido , Pneumopatias/epidemiologia , Masculino , Estudos Prospectivos , Síndrome do Desconforto Respiratório do Recém-Nascido/complicações , Síndrome do Desconforto Respiratório do Recém-Nascido/mortalidadeRESUMO
A multicenter prospective, randomized controlled trial was conducted to determine whether early use of platelet concentrates would reduce the incidence or extension of intracranial hemorrhage or both in sick preterm infants with thrombocytopenia. The effects on bleeding as reflected by the amount of blood product support administered and a shortened bleeding time were assessed as secondary outcomes. Premature infants with a platelet count < 150 x 10(9)/L within the first 72 hours of life were randomly assigned to receive either conventional therapy or conventional therapy plus platelet concentrates (10 ml/kg). The platelet count was maintained < 150 x 10(9)/L until day 7 of life by one to three platelet transfusions. In 22 (28%) of the 78 treated infants and 19 (26%) of the 74 control infants, either a new intracranial hemorrhage developed or an already-present one became more extensive (p = 0.73). Similar numbers of infants had each grade of intracranial hemorrhage on both initial and follow-up ultrasonography. Similar numbers of infants received fresh frozen plasma and packed red blood cells, but treated infants received less of both. The bleeding time was prolonged in the treated group before the infusion of platelet concentrates but subsequently shortened (mean difference, 79.0; 95% confidence interval, 73.1 to 84.9). Subanalysis of the control group showed that infants with platelet counts < 60 x 10(9)/L (n = 21) on at least one occasion received more fresh frozen plasma and packed red blood cells than did those with platelet counts > 60 x 10(9)/L.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Transfusão de Componentes Sanguíneos , Doenças do Prematuro/terapia , Trombocitopenia/terapia , Canadá , Hemorragia Cerebral/sangue , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Eritrócitos , Feminino , Humanos , Recém-Nascido , Doenças do Prematuro/sangue , Masculino , Plasma , Contagem de Plaquetas , Estudos Prospectivos , Trombocitopenia/sangue , Trombocitopenia/complicações , Fatores de Tempo , UltrassonografiaRESUMO
To investigate claims that oscillating mattresses reduce apnea of prematurity and improve growth and neurobehavioural development, we performed a randomized clinical trial using a predetermined sample size. Preterm infants weighing from 750 to 1750 gm at birth were randomly assigned, by 250 gm strata, to either a conventional mattress (n = 63) or to an air mattress (n = 59) oscillating at 14 to 16 regular pulses per minute. Infants remained on the oscillating air mattress for at least 7 days or until 34 weeks postmenstrual age. Apneic episodes occurred and required treatment equally in the two groups; this lack of an effect was seen for both sexes and all weight groups. Both weight and energy intake were similar. Neurobehavioral development as shown by sleep state, habituation testing, and behavioral assessment at term, 3, 6, and 12 months was similar in the two groups. There was no difference in the incidence of neurologic abnormalities. We conclude that an oscillating air mattress has no prophylactic value in reducing apnea and does not enhance growth and development.
Assuntos
Apneia/prevenção & controle , Leitos , Desenvolvimento Infantil , Crescimento , Doenças do Prematuro/prevenção & controle , Ar , Apneia/epidemiologia , Apneia/terapia , Peso ao Nascer , Peso Corporal , Bradicardia/epidemiologia , Comportamento Infantil , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Habituação Psicofisiológica , Humanos , Recém-Nascido , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/terapia , Masculino , Distribuição Aleatória , Respiração ArtificialRESUMO
To measure the radiation environment in the Spacelab (SL) module and on the pallet, a set of passive and active radiation detectors was flown as part of the Verification Flight Instrumentation (VFI). SL 1 carried 4 passive and 2 active detector packages which, with the data from the 26 passive detectors of Experiment INS006, provided a comprehensive survey of the radiation environment within the spacecraft. SL 2 carried 2 passive VFI units on the pallet. Thermoluminescent dosimeters (TLDs) measured the low linear energy transfer (LET) dose component; the HZE fluence and LET spectra were mapped with CR-39 track detectors; thermal and epithermal neutrons were measured with the use of fission foils; metal samples analyzed by gamma ray spectroscopy measured low levels of several activation lines. The TLDs registered from 97 to 143 mrad in the SL 1 module. Dose equivalents of 330 +/- 70 mrem in the SL 1 module and 537 +/- 37 mrem on the SL 2 pallet were measured. The active units in the SL 1 module each contained an integrating tissue-equivalent ion chamber and two differently-shielded xenon-filled proportional counters. The ion chambers accumulated 125 and 128 mrads for the mission with 17 and 12 mrads accumulated during passages through the South Atlantic Anomaly (SAA). The proportional counter rates (approximately 1 cps at sea level) were approximately 100 cps in the middle of the SAA (mostly protons), approximately 35 cps at large geomagnetic latitudes (cosmic rays) and approximately 100 cps in the South Horn of the electron belts (mostly bremsstrahlung). Detailed results of the measurements and comparison with calculated values are described.
Assuntos
Radiação Cósmica , Partículas Elementares , Monitoramento de Radiação/instrumentação , Voo Espacial/instrumentação , Astronave/instrumentação , Oceano Atlântico , Radioisótopos de Cobalto/isolamento & purificação , Desenho de Equipamento , Raios gama , Doses de Radiação , América do Sul , Dosimetria Termoluminescente/instrumentaçãoRESUMO
Fifteen enterally fed preterm infants not receiving additional trace element supplements and 22 preterm infants receiving total or partial parenteral nutrition supplemented with zinc at 350 micrograms/kg/day and copper at 20 micrograms/kg/day were examined 1, 7, 14, 21, and 28 days after birth. Mean serum Zn concentrations in the parenteral group remained relatively constant and were significantly higher (P less than 0.01) at day 21 than the value for the enteral group. In contrast, a significant decline in mean serum Zn concentrations occurred between days 1 and 21 in the enteral group. The mean serum Cu concentrations in the parenteral group rose during the first week, and were significantly higher at days 14 and 21 than corresponding values in the enteral group. This trend did not result from copper supplementation alone but was also attributed to the presence of ceruloplasmin in blood transfusions. Mean serum Se concentrations did not change significantly, either between or within the two groups, except during the first week, at which time levels rose in the parenteral group. The addition of Zn, Cu, and probably of Se to parenteral infusates, allows the maintenance of appropriate serum values.