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Introduction: Inhaled nitric oxide (NO) may be beneficial in the treatment of pulmonary hypertension, both of the newborn and in the adult respiratory distress syndrome. Up to now, serious systemic side effects have not been reported.Objective: The effect of inhaled NO on superoxide anion production by neutrophils.Design: Prospective study of a consecutive series of 15 neonates and infants.Setting: Neonatal and paediatric ICUs with a total of 17 beds (university hospital).Measurements and Results: Superoxide anion production was determined by a flow cytometric method using dihydrorhodamine 123 (DHR) as an oxidative probe after the priming of neutrophils with N-formyl-methionyl- leucylphenylalanine (fMLP) or with Escherichia coli. The generated fluorescence was expressed as relative fluorescence intensity (RFI). Inhalation of NO for more than 24 h reduced the superoxide anion production by neutrophils stimulated with E. coli to below baseline values before NO inhalation (mRFI = 158 +/- 25 vs 222 +/- 24; P = 0.03). This decrease was more pronounced after more than 72 h (mRFI = 133 +/- 17). At this time, superoxide anion production by fMLP-stimulated neutrophils was also decreased (mRFI = 40 +/- 3, vs 57 +/- 5; P = 0.03). The reduced capacity of superoxide production persisted throughout therapy with NO and lasted up to more than 4 days after the end of NO inhalation.Conclusion: The results suggest that inhalation of NO in patients with pulmonary hypertension causes reduced superoxide anion production by neutrophils stimulated with E. coli or with fMLP. To determine the clinical importance of this systemic side effect with respect to bacterial infections, a randomized controlled study is necessary. [ABSTRACT FROM AUTHOR]

Unlabelled: Inhaled nitric oxide (NO) is thought to provide a noninvasive therapeutic alternative to extracorporeal membrane oxygenation (ECMO) in the treatment of persistent pulmonary hypertension of the newborn (PPHN).Objective: Since January 1993, we have studied inhalation of NO in PPHN patients meeting the ECMO criteria of our institution. We focused on the questions of whether or not the need for ECMO could be obviated and whether differences could be found between NO responders and nonresponders.Design: NO gas was delivered via conventional IPPV ventilation in incrementally increasing concentrations from 20 to 80 ppm.Patients: NO therapy was attempted in ten ECMO candidates with clinical and echocardiographical evidence of PPHN (mean OI 51.9, SD 10.4).Results: At various NO levels (30-60 ppm), five patients showed a significant increase in mean PaO2 (range 32.9-85.9 mmHg). Improvement was transient in three patients (6-10 h) and prolonged in two others (54-80 h); in the latter cases, ECMO was avoided. Five patients did not respond at all to treatment. Responders and nonresponders differed in their mean respiratory tidal volume (8.9 vs 4.18 ml/kg, P <0.05).Conclusions: In our study, inhalation of NO obviated the necessity of ECMO therapy in only two out of ten PPHN patients. Thus, we would discourage any overoptimistic expectations about the effectiveness of NO therapy in PPHN until larger clinical trials have been performed. [ABSTRACT FROM AUTHOR]

As part of a multicenter surfactant rescue study, the chest X-rays of 239 preterm and term infants were analyzed. To study the influence of surfactant administration on radiographic appearance, 130 patients with a clinical and radiological diagnosis of typical respiratory distress syndrome were selected, in whom adequate chest x-rays before and within 48 h after treatment were available. Median gestational age was 30 weeks (range 25-38 weeks), median birth weight was 1335 g (range 625-3450). The time of surfactant application ranged between 90 min and 24 h after birth (median 6 h). The most common finding after surfactant administration was uniform (n = 47) or disproportionate (n = 46) improvement of pulmonary aeration, which showed a significant correlation to posttreatment reduction of oxygen requirement (p less than 0.0001). Asymmetric clearance was more often localized on the right side and usually disappeared within two to five days. Only in 13 patients no change of ventilation was found. Development of interstitial emphysema (n = 24, including three patients with pneumothorax) after surfactant treatment was an unfavourable prognostic sign. 54% of these patients (13 of 24) died within the first month of life, compared to 8% (7 of 93) in the group of patients with initial improvement of ventilation. [ABSTRACT FROM AUTHOR]

We report on 50 term and near-term neonates (birth weight greater than 1800 g, gestational age greater than 33 weeks) with severe persistent pulmonary hypertension of the newborn (PPHN), referred to us from January 1987 to July 1991 after failure of maximum conventional treatment. All infants had paO2 less than 45 mm Hg when ventilated with peak inspiratory pressure greater than 38 cm H2O and FiO2 = 1.0, hence meeting entry criteria for extracorporeal membrane oxygenation (ECMO). High frequency oscillatory ventilation (HFOV) was tried in all patients. If sufficient oxygenation could not be achieved (paO2 less than 40 mm Hg for at least 2 h), ECMO therapy was begun, which was the case in 25 children. Neonates responding to HFOV (n = 25) were of a slightly younger gestational age (37.0 weeks vs 38.8 weeks, P less than 0.05), had higher Apgar scores and were less hypoxaemic before HFOV (paO2 36.6 mm Hg vs 28.8 mm Hg, P less than 0.01); during HFOV there was a significant rise in paO2 (greater than 150 mm Hg; P less than 0.001) and a fall in pCO2 to 21.6 mm Hg (P less than 0.001). Due to air leaks, which was the main complication of HFOV (52%), ECMO therapy had to be begun in two additional infants after an initial positive effect. HFOV tended to be successful in cases of primary PPHN, meconium aspiration and sepsis, but not in infants with lung hypoplasia as a result of diaphragmatic hernia or other reasons. Success or failure of HFOV could not be reliably predicted by any parameter.(ABSTRACT TRUNCATED AT 250 WORDS) [ABSTRACT FROM AUTHOR]