Pulmonary outcome and its correlates in school-aged children born with a gestational age ≤ 32 weeks.

BACKGROUND: There is limited data regarding factors influencing the respiratory outcome at school age of ex-preterms born since the introduction of antenatal steroids, surfactant replacement together with less aggressive ventilation. OBJECTIVES: To establish the main antenatal, neonatal and early childhood respiratory correlates of respiratory status in school-aged children born at ≤ 32 weeks of gestation. METHODS: Ex-preterm children born at ≤ 32 weeks of gestation between 1997 and 2001 at Bordeaux University Hospital were evaluated at school age, using a respiratory questionnaire and lung function tests (spirometry, plethysmography, exercise challenge test and CO lung diffusing capacity DLCO measurements). Factors associated with lung function were investigated using polynomial regression analyses. RESULTS: Of the 151 included children [mean age: 8.6 ± 0.8 years; mean gestational age, 30.1 ± 1.7 weeks; mean birth weight = 1310 ± 380 g; 68.2% ventilated at birth; 46.4% treated with surfactant; 36.4% with prior bronchopulmonary dysplasia (BPD)], 47% presented obstructive lung abnormalities, 11% restrictive or mixed lung abnormalities, 41% exercise-induced bronchoconstriction, and 15.5% reduced DLCO. Surfactant therapy was independently associated with a lower risk of lung abnormalities (p < 0.05). The association between BPD and lung abnormalities at school age was not significant, but prior BPD increased the risk of restrictive or mixed abnormalities (odds ratio: 6.11, confidence interval [1.1; 33.99]). Early childhood respiratory events were not associated with the occurrence of lung abnormalities. CONCLUSION: Children born at ≤ 32 weeks of gestation remain at risk for impaired lung function at school age in particular when they did not receive surfactant. Restrictive or mixed lung defects are mainly associated with prior BPD.

Hallerman-Streiff-like syndrome presenting with laterality and cardiac defects.

We report two patients considered to have an atypical presentation of Hallerman-Streiff syndrome (HSS) associated with laterality and cardiac defects. Clinical features include typical facial gestalt, atrophy of the skin, and hypotrichosis. Ophthalmologic abnormalities, normally present in HSS, are only found in one of the two patients. Both of them have respiratory problems secondary to the classical narrow upper airway described in this syndrome. Both these patients have laterality defects and one has additional structural cardiac malformations. Cardiac defects have occasionally been reported in the HSS literature, but are not considered as a classical feature of the syndrome. Situs inversus has never been reported in this syndrome. Almost all HSS cases have been sporadic and their origin and inheritance pattern remain unknown.

Efficacy and tolerance of high-dose inhaled ipratropium bromide vs. terbutaline in intubated premature human neonates.

BACKGROUND: There is insufficient data to reliably assess the benefit of bronchodilators in ventilated premature neonates. OBJECTIVES: To compare the efficacy/tolerance of inhaled ipratropium bromide (IB) vs. terbutaline (T) and to describe factors associated with their efficacy. METHODS: A cross-over randomized controlled double-blind trial including intubated neonates with respiratory distress syndrome. Two puffs of IB or T were administered at 0, 20, 40 min. Passive respiratory system resistance (Rrs) and compliance (Crs) were measured at 0, 20, 40, 60 min. A positive response was defined as a >2 individual coefficients of variation decrease in Rrs or increase in Crs. RESULTS: Twenty-one infants (gestational age (mean +/- SD): 27.3 +/- 1.6 weeks; birth weight: 947 +/- 250 g; postnatal age: 20 +/- 9 days) were included. At 60 min, no treatment effect for Rrs and Crs could be identified (cross-over analysis). Overall data (irrespective of order of administration) showed that after 6 puffs, the decrease in Rrs was greater in the IB vs. T group (-17.0 +/- 22.2% vs. -11.3 +/- 26.7%, respectively (NS)). Thirty-eight percent of infants responded to IB vs. 43% to T. However, in 19% of patients, decreased Crs was observed after 6 puffs of T. No marker of a positive or paradoxical response could be identified. Treatment was well-tolerated. CONCLUSION: High doses of bronchodilators are required in ventilated neonates, but the positive response rate was <50%. Their long-term benefit remains to be proven.

Pharmacologically induced relaxation of tracheal smooth muscle is increased in hyperoxia-exposed 15-day-old rats.

Hyperoxia increases maximum airway contractility in newborn guinea pigs and immature rats. Studies examining the mechanisms of hyperoxia-induced airway hyperresponsiveness have focused on contractile mechanisms, although excessive airway narrowing could be due to impaired relaxation. Our objective was to determine the effects of hyperoxia on airway structure and relaxing properties in juvenile rats exposed to an inspired fraction of oxygen (FiO(2)) of 0.5 within 24 hr of birth for 15 days, compared to a control group of air-exposed rats. We studied the 1) tracheal smooth muscle surface area; and 2) in vitro relaxation in precontracted (carbachol, 1.10(-3) M) isolated tracheal rings to increasing cumulative concentrations (10(-8) to 10(-4) M) of salbutamol. There was no significant difference in the amount of smooth muscle between the hyperoxia and air-exposed groups. Maximal relaxation of the isolated trachea to salbutamol was greater in the hyperoxia group than in the air-exposed group when normalized to smooth muscle surface area (-12.69 +/- 3.51 g/mm(2) vs. - 8.49 +/- 1.67 g/mm(2); P (MANOVA) < 0.05) or expressed as maximal relaxation induced by 10(-3) M theophylline (61% vs. 28%; P < 0.05). In conclusion, salbutamol-induced relaxation is enhanced (and not impaired) in newborn rats exposed to prolonged moderate hyperoxia.