Biology of the neonate
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Biology of the neonate · Jan 1998
Randomized Controlled Trial Comparative Study Clinical TrialA comparison of underwater bubble continuous positive airway pressure with ventilator-derived continuous positive airway pressure in premature neonates ready for extubation.
As the result of vigorous bubbling, infants receiving continuous positive airway pressure (CPAP) by an underwater seal (bubble CPAP) were observed to have vibrations of their chests at frequencies similar to high-frequency ventilation (HFV). We performed a randomized crossover study in 10 premature infants ready for extubation to test whether bubble CPAP contributes to gas exchange compared to conventional ventilator-derived CPAP. Measurements of tidal volume and minute volume were made using the Bear Cub neonatal volume monitor, and gas exchange was measured using an oxygen saturation monitor and a transcutaneous carbon dioxide (tcpCO2) monitor. ⋯ The lack of difference in blood gas parameters associated with a decrease in the infant's minute volume and respiratory rate with bubble CPAP compared with ventilator-derived CPAP suggests that the chest vibrations produced with bubble CPAP may have contributed to gas exchange. Bubble CPAP may offer an effective and inexpensive option for providing respiratory support to premature infants.
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Biology of the neonate · Jan 1998
Randomized Controlled Trial Clinical TrialHyperglycemia in extremely- low-birth-weight infants.
The cause of hyperglycemia in extremely-low-birth-weight (ELBW) infants is not well understood. We studied infants weighing <1,000 g to investigate the relationship of hyperglycemia to blood levels of insulin-like growth factor (IGF)-I and IGF-II. We also compared two methods of treatment for hyperglycemia: continuous insulin infusion and reduction of glucose intake. ⋯ IGF-I and IGF-II are not related to hyperglycemia. In our population, hyperglycemic infants did not have baseline insulin deficiency and most had a normal insulin response to hyperglycemia. Insulin infusion appears safe in these infants and helped to maintain normal caloric intake, whereas glucose reduction was associated with a prolonged caloric deprivation.
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Biology of the neonate · Jan 1998
Dexamethasone for pulmonary interstitial emphysema in preterm infants.
The efficacy of a 3-day course of dexamethasone (0.5 mg/kg/ day) in 10 preterm infants (< or = 30 weeks gestation) with pulmonary interstitial emphysema (PIE) was studied in a retrospective case review. PIE was diagnosed at a median age of 7.5 days and treatment with dexamethasone began at 8.5 days. Seven of the 10 subjects had at least 2 days of conservative treatment (lowered mean airway pressure) preceding dexamethasone during which the mean airway pressure (MAP), oxygenation index (OI) and mechanical ventilation index (MVI) were not significantly different although within 3 days of dexamethasone each variable improved significantly (p < 0.05). ⋯ Nine of the 10 infants survived to term. Three days of dexamethasone was associated with significant clinical improvement in most of these infants. The mechanism may relate to reduced airway oedema and inflammation and reduced airway obstruction.
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Biology of the neonate · Jan 1998
Insulin-like growth factor binding protein 1 level in amniotic fluid: correlation with birth weight.
Insulin-like growth factor binding protein 1 is the predominant insulin-like growth factor binding protein in amniotic fluid. It is produced by the decidua and by fetal tissues, and it is thought to play an important role in fetal growth. We have measured this protein in 58 samples of amniotic fluid, from 13 to 19 gestational weeks, and found a highly significant negative correlation with fetal weight at birth. We conclude that the level of insulin-like growth factor binding protein 1 in amniotic fluid at midpregnancy is a good marker of fetal growth failure.
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Biology of the neonate · Jan 1998
Enhancement of surfactant effect by a mechanical volume recruitment maneuver depends on the lungs preexisting distension.
'Rescue' surfactant treatment of premature infants with respiratory distress syndrome (RDS) results in two mechanisms: stabilization of alveoli already being ventilated and recruitment of alveoli collapsed before surfactant administration. Mechanical recruitment of alveoli from this collapsed compartment might enhance the immediate effects of surfactant treatment. To test this hypothesis 15 mechanically ventilated young rabbits underwent repeated airway lavage with normal saline at a constant, positive end-expiratory pressure (PEEP) of 3 cm H2O until both the a/A ratio was < 0.12 and a peak inspiratory pressure (PIP) > 20 mbar was needed to keep the tidal volume (VT) at 10 ml/kg. ⋯ There were no differences between the surfactant and the VRM + surfactant groups for all indices assessed after an observational period of 2 h following surfactant administration. In a previous model using a PEEP of 1 cm H2O [Krause et al., Am J Respir Crit Care Med 1997;156:862-866], significant differences have been disclosed for Crs, VT and FRC. In conclusion, the enhancement of surfactant effect by VRM largely depends on the preexisting distension of the lungs.