Respiratory distress, neonatal

Example 6.1 Effect of betamethasone on incidence of neonatal respiratory distress... 

This randomised trial (Stutchfield et al. (2005)) investigated the effect of betamethasone on the incidence of neonatal respiratory distress after elective caesarean section. Of the 503 women randomised to the active treatment, 11 babies were subsequently admitted to the special baby unit with respiratory distress compared to 24 babies out of 495 women randomised to the control group. 

Storosum JG, van Zwieten BJ, Vermeulen HDB, Wohlfarth T et al (2001) Relapse and recurrence in major depression a critical review of placebo-controUed efficacy studies with special emphasis on methodological issues European Psychiatry, 16, ill- i iS Stutchfield P, Whitaker R and Russell I, on behalf of the Antenatal Steroids for Term Elective Caesarean Section (ASTECS) Research Team (2005) Antenatal betamethasone and incidence of neonatal respiratory distress after elective caesarean section pragmatic randomised trial British Medical Journal, 331, 662-667... 

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). 

Therapeutically, lecithin and derivatives have been used as a pulmonary surfactant in the treatment of neonatal respiratory distress syndrome. 

Once one knows the problem and has devised a solution, then the real job begins. National Center for Health Statistics data show a decline in total US infant mortality from 1982 to 1992, but marked geographic and racial differences remain. The 1992 overall US rate of infant death was 8.5 per 1000 live births (California, 6.9 Texas, 7.7 New York, 8.5 New Jersey, 8.5 Pennsylvania, 8.6 Ohio, 8.7 Florida, 9.1 Illinois, 10.0 Georgia, 10.4 Michigan, 10.5) - a decline attributed not to reductions in the numbers of birth defects or premature births but to improved neonatal intensive care units and the introduction of synthetic pulmonary surfactants and consequent reductions in death from acute neonatal respiratory distress syndrome. Still, the years of potential life lost due to birth defects ranks fifth, just behind that of homicide and suicide (1, unintentional injury 2, cancer 3, cardiovascular disease) prematurity/low birth weight ranks sixth and sudden infant death syndrome seventh. Ethnic discrepancy remains pronounced rates of White (5.8 per 1000 live births) and Cuban Hispanic (3.7 per 1000 live births) infant death are similar, but the 2002 rate for Blacks (13.9 per 1000 live births) increased compared to the previous year. 

Increased Utilization. Secondarily low levels of AAT are seen in the neonatal respiratory distress syndrome, severe neonatal hepatitis, and severe preterminal disease of the pancreas. In nonfatal pancreatitis, levels increase along with those of other APR, and increased levels of complexes with trypsin are probably a better marker for use in either differential diagnosis or prognosis in patients with possible pancreatitis. 

Wijnberger LD, Huisjes AJ, Voorbij HA, Franx A, Bruinse HW, Mol BW. The accuracy of lamellar body count and lecithin/sphingomyelin ratio in the prediction of neonatal respiratory distress syndrome a meta-analysis. BJOG 2001 108 583-8. 

The delivery of aerosol powders by generation with minimal formulation has been an attractive prospect to many researchers. The early use of a dry powder artificial phospholipid in the treatment of neonatal respiratory distress syndrome proved very successful [181]. Because no delivery system was available to facilitate this treatment, a simple system was devised. A Laerdal neonatal resuscitation bag was modified to hold a capsule containing the artificial surfactant, as shown schematically in Fig. 11. However, where MDIs of the prescribed medication are available, both physicians and patients prefer their use. The powders themselves have to be prepared in the same way as those used in MDIs, by milling. Often, excipients are added to carry the fine powder. Lactose has been used in both cromolyn sodium and albuterol formulations. As a consequence of the interest in dry powders, a number of products have been... 

Instillation of surfactant improves outcome in premature infants with neonatal respiratory distress. Loss of surfactant is probably a contributing factor in pathogenesis of acute respiratory distress syndrome in adults, so there has been an... 

Surfactant aerosol also has been tested in chronic bronchitis the modest improvement in FEV1 was small, and its expense would not justify use based on these data [175]. In tests of aerosol surfactant in adults with CF treated over 5 days, no improvement was found [176]. Although instilled surfactant has become common practice for the neonatal respiratory distress of premature infants, aerosol delivery is not yet adequately developed. A recent study showed no difference in outcome for spontaneously breathing newborns who inhaled either surfactant or placebo via a CPAP mask [177]. There continues to be great appeal for the use of surfactant in adults because of the apparent success in neonates, but its use should not become practice until well-controlled trials document clinically meaningful efficacy. 

Neonatal respiratory distress syndrome (RDS) is predominantly a disease of surfactant deficiency. 

This chapter addresses the problems of acute respiratory distress syndromes in neonates, children, and adults. Abbreviations are used throughout the text, and a glossary for physiology, diseases, and drugs is presented in Table 28-1. Descriptions of ventilator-related terms are provided in Tables 28-2 and 28-3. Because the physiology of neonatal respiratory distress syndrome (RDS) and acute respiratory distress syndrome (ARDS) has some differences, these diseases will be discussed separately. 

Soil RE, Blanco F. Natural surfactant extract versus synthetic surfactant for neonatal respiratory distress syndrome (systematic review). Cochrane Database Syst Rev 2001 2. 

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