Neonatal respiratory distress syndrome prevention

In 534 individuals aged 30 years, whose mothers had participated in a double-blind, randomized, placebo-controlled trial of antenatal betamethasone (two intramuscular doses 24 hours apart) for the prevention of neonatal respiratory distress syndrome, there were no differences between those exposed to betamethasone and placebo in body size, blood lipids, blood pressure, plasma cortisol, prevalence of diabetes, or history of cardiovascular disease (397). After the oral glucose tolerance test, those who had been exposed to betamethasone had higher plasma insulin concentrations at 30 minutes (61 versus 52 mIU/1) and lower glucose concentrations at 120 minutes (4.8 versus 5.1 mmol/1) than did those exposed to placebo. Antenatal exposure to betamethasone might result in insulin resistance in adult offspring, but has no effect on cardiovascular risk factors at 30 years of age. 

In 192 adult offspring (mean age 31 years) of mothers who had taken part in a randomized controlled trial of antenatal betamethasone for the prevention of neonatal respiratory distress syndrome (87 exposed to betamethasone two doses 24 hours apart, and 105 exposed to placebo) there were no alterations in cognitive functioning, working memory and attention, psychiatric morbidity, handedness, or health-related quality-of-life in adulthood (400). 

In an analysis of 595 preterm infants born at 26-32 weeks gestation during a randomized controlled trial for the prevention of lung disease, glucocorticoids given to women at risk of preterm delivery promoted fetal lung maturation, reduced the incidence of respiratory distress syndrome, and reduced neonatal morbidity and mortality (370). Dexamethasone was given as either two doses of 12 mg 24 hours apart or four doses of 6 mg every 6 hours. Mortality was 9.2% after three or more courses, compared with 4.8% after one or two courses. This association was not explained by other factors (maternal or other common preterm morbidities). 

Soil, R. F., Merritt, T. A., and Hallman, M. (1994). Surfactant in the prevention and treatment of respiratory distress syndrome. In New Therapies for Neonatal Respiratory Failure A Physiologic Approach (B. R. Boynton, W. A. Carlo, A. H. Jobe, eds.), pp. 49-80. Cambridge University Press, New York. 

Use of contrast medium is contraindicated in renal failure. In general, contrast medium may decrease renal blood flow and cause contrast nephropathy with acute renal failure (Murphy et al. 2000). Contrast medium should be avoided in neonates even with normal renal function. If indicated (e.g., for cardiac catheterization), adequate hydration of the neonate is mandatory. Administration of the adenosine antagonist theophylline seems to be a promising means of preventing contrast nephropathy (Kolonko et al. 1998 Huber et al. 2006). This is also of value in neonates and preterm neonates, where theophylline was reported to improve renal function in neonates with respiratory distress syndrome (Huet et al. 1995 Cattarelli et al. 2006). 

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