No abstract

BACKGROUND: Inhaled nitric oxide (iNO) is an effective therapy for pulmonary hypertension and hypoxic respiratory failure in term infants. Fourteen randomized controlled trials (n ϭ 3430 infants) have been conducted on preterm infants at risk for chronic lung disease (CLD). The study results seem contradictory. DESIGN/METHODS:Individual-patient data meta-analysis included randomized controlled trials of preterm infants (Ͻ37 weeks' gestation). Outcomes were adjusted for trial differences and correlation between siblings. RESULTS:Data from 3298 infants in 12 trials (96%) were analyzed. There was no statistically significant effect of iNO on death or CLD (59% vs 61%: relative risk [RR]: 0.96 [95% confidence interval (CI): 0.92-1.01]; P ϭ .11) or severe neurologic events on imaging (25% vs 23%: RR: 1.12 [95% CI: 0.98 -1.28]; P ϭ .09). There were no statistically significant differences in iNO effect according to any of the patient-level characteristics tested. In trials that used a starting iNO dose of Ͼ5 vs Յ5 ppm there was evidence of improved outcome (interaction P ϭ .02); however, these differences were not observed at other levels of exposure to iNO. This result was driven primarily by 1 trial, which also differed according to overall dose, duration, timing, and indication for treatment; a significant reduction in death or CLD (RR: 0.85 [95% CI: 0.74 -0.98]) was found.CONCLUSIONS: Routine use of iNO for treatment of respiratory failure in preterm infants cannot be recommended. The use of a higher starting dose might be associated with improved outcome, but because there were differences in the designs of these trials, it requires further examination.

Betamimetics help to delay delivery for women transferred to tertiary care or completed a course of antenatal corticosteroids. However, multiple adverse effects must be considered. The data are too few to support the use of any particular betamimetics.

Aims: To establish a practical postnatal reference range for cardiac troponin T in neonates and to investigate concentrations in neonates with respiratory distress. Methods: Prospective investigation in a tertiary neonatal unit, recruiting infants with and without respiratory distress (sick and healthy infants respectively). Concentrations of cardiac troponin T were compared between sick and healthy infants, accounting for confounding variables. Results: A total of 162 neonates (113 healthy and 49 sick infants) had samples taken. The median (interquartile range) cardiac troponin T concentration in the healthy infants was 0.025 (0.01-0.062) ng/ ml, and the 95th centile was 0.153 ng/ml. There were no significant relations between cardiac troponin T and various variables. The median (interquartile range) cardiac troponin T concentration in the sick infants was 0.159 (0.075-0.308) ng/ml. This was significantly higher (p , 0.0001) than in the healthy infants. In a linear regression model, the use of inotropes and oxygen requirement were significant associations independent of other basic and clinical variables in explaining the variation in cardiac troponin T concentrations. Conclusions: Cardiac troponin T is detectable in the blood of many healthy neonates, but no relation with important basic and clinical variables was found. Sick infants have significantly higher concentrations than healthy infants. The variations in cardiac troponin T concentration were significantly associated with oxygen requirement or the use of inotropic support in a regression model. Cardiac troponin T may be a useful marker of neonatal and cardiorespiratory morbidity.

Aim-To determine whether treatment with inhaled nitric oxide (NO) and/or dexamethasone reduces the incidence of chronic lung disease (CLD) and/or death in high risk preterm infants. Methods-Infants below 32 weeks of gestation were recruited at 96 hours of age if they were deemed to be at high risk of developing CLD. Infants were randomly assigned to one of four treatment groups using a factorial design: (1) 5-20 parts per million inhaled NO for 72 hours; (2) 0.5-1 mg/kg/day intravenous dexamethasone for 6 days; (3) both drugs together; (4) continued conventional management. Results-Forty two infants were randomised: 10 infants received inhaled NO alone; 11 dexamethasone alone; 10 both treatments; and 11 neither treatment. There was no diVerence in the combined incidence of CLD and/or death before discharge from hospital between either infants treated with inhaled NO and controls (RR 1.05, 95% CI 0.84-1.25), or those treated with dexamethasone and controls (RR 0.95, 95% CI 0.79-1.18). Conclusions-At 96 hours of age, neither treatment with inhaled NO nor dexamethasone prevented CLD or death. (Arch Dis Child 1997;77:F185-F190)