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The aim of this update is to describe, in the context of the current literature, major s from the seven groups of the Paediatric Assembly (Respiratory Physiology; Asthma and Allergy; Cystic Fibrosis; Respiratory Infection and Immunology; Neonatology and Paediatric Intensive Care; Respiratory Epidemiology; and Bronchology) presented during the annual European Respiratory Society congress held in 2017 in Vienna, Austria. Introduction During the 2017 annual congress of the European Respiratory Society (ERS) in Vienna, Austria, members of the Paediatric Assembly presented numerous high-quality scientific communications. As for the Scientific Assembly Update from the 2017 annual congress [1], the chairs of the scientific groups of the Paediatric Assembly have selected and discussed the most important abstracts from each group, to give colleagues who were unable to attend the congress or a specific session a review of the research presented during the meeting. Due to the large number of contributions to the congress this summary cannot be comprehensive, but rather aims to address schemes of new research in major areas of paediatric respiratory medicine. Forced oscillation Several studies in recent years have investigated how the various lung function techniques can be applied in clinical practice in young children. The ERS conference in Vienna reflected this tendency. For example, ALBLOUSHI et al. [2] studied the feasibility and safety of mannitol challenge using the forced oscillation technique (FOT) in 16 preschool children (aged 3–7 years). Only two children aged 3-years were unable to do the test, giving a feasibility of 87%. No adverse events were ed, leading the investigators to conclude that the mannitol challenge test using FOT is feasible and safe in preschool children. In another study using the FOT, IOAN et al. [3] assessed the bronchodilator response (BDR) to a single pressure oscillation at 8 Hz in 79 asthmatics and 20 controls aged 4–11 years. The BDR test showed a higher Youden index (a combination of sensitivity and specificity in discriminating asthmatics from controls) during inspiration than during expiration for several FOT indices, suggesting that the inspiratory BDR may help in diagnosing asthma in children. Similarly, RADICS et al. [4] assessed within-breath changes in respiratory impedance in 37 healthy newborns during natural sleep using forced oscillations at 16 Hz with the wave tube technique [5]. They found that respiratory resistance depended more on flow than on volume, showing flow nonlinearities in the narrow airways. The wave tube technique is an exceedingly promising tool for measuring lung function in unsedated infants. In a later study, HANTOS et al. [6] ed 88% feasibility in healthy 1-day-old newborns. Multiple breath washout Several studies addressed the multiple breath washout (MBW) technique, most were designed to evaluate its potential applications in clinical practice. RATJEN et al. [7] used the reference standard sulfur hexafluoride mass spectrometer-based MBW system to validate a recently released nitrogen washout ultrasonic flow meter-based commercial system in 24 healthy children and 33 children with cystic fibrosis (CF). They found that the lung clearance index (LCI) was systematically 0.2 units (95% CI 0.06–0.33) lower with sulfur hexafluoride than with nitrogen washout, confirming that the values obtained with the two techniques cannot be used interchangeably. Interestingly, the mean LCI difference was greater in children with CF (0.4 units, 95% CI 0.29–0.55). Using a different nitrogen washout ultrasonic flow meter-based commercial system, FUCHS et al. [8] differentiated 11 patients with CF (aged 7–25 years) from 19 healthy controls (aged 7–51 years). The mean±SD LCI was 6.5±0.64 units in controls and 9.3±1.93 units in CF with a mean difference of -2.83 (95% CI -4.14– -1.51; p<0.001) between the groups. Within-test repeatability (coefficient of variation %) was 5.3% in controls and 7.7% in CF. These results support the conclusion that MBW of nitrogen can differentiate patients with CF from controls, as previously published data have shown for MBW of sulfur hexafluoride [9]. In a clinical and imaging study, HATZIAGOROU et al. [10] used MBW and low-dose chest computed tomography (CT) in 14 subjects with non-CF bronchiectasis and normal forced expiratory volume in 1 s (FEV1). They found that LCI had 87% sensitivity and 50% specificity in detecting structural lung damage as shown by CT scans. These results suggest that LCI may be a suitable surrogate marker for monitoring progression of lung disease among children with non-CF bronchiectasis. The same group compared LCI and exercise capacity in 15 children with stable CF (mean age 13.7 years), 14 children with stable non-CF bronchiectasis (mean age 13.8 years) and 15 healthy children (mean age 13.6 years) [11]. While the mean LCI was significantly higher among patients with CF and those with non-CF bronchiectasis (13.7 and 11.8 units, respectively) than in healthy children (p<0.001), no significant difference was found between children with CF and non-CF bronchiectasis (p=0.16). Similar results were found for exercise capacity: no significant difference was found between the mean peak aerobic capacity in children with CF and those with non-CF bronchiectasis (62.2% predicted versus 77.3% pred) (p=0.06), whereas both groups differed significantly from controls (p<0.001). In a similar study, GREEN et al. [12] compared MBW in 24 children with primary ciliary dyskinesia (PCD) (mean age 13.0 years) and 25 children with CF (mean age 12.3 years). They found that LCI and ventilation inhomogeneity indices in the conductive and acinar airway zones were abnormal, but not significantly different, in the two groups. These results suggest that, in contrast to the lower morbidity usually seen in children with PCD than in those with CF, the severity of peripheral airway involvement is similar in children with these diseases. Reference values Proper reference values are essential for interpreting lung function measurements [13]. As part of the Global Lungs Initiative (GLI) () and an ERS Task Force, STOCKS et al. [14] ed global reference equations for spirometry from 74 187 healthy nonsmokers aged from three to 95 years. Reference equations for Caucasians, African Americans, south-east Asians and north-east Asians were produced using modern statistical methods and assessing age-dependent lower limits of normality. For individuals not represented by these four groups a composite equation was provided. The GLI reference equations 2017 for spirometry are a major step forward [15] and their widespread use will depend on timely implementation by manufacturers of spirometric devices. Studying another possible reference tool, ULRICH et al. [16] ed reference equations for the 6-min walk test (6MWT), a simple and reliable tool [17] to assess exercise capacity in various chronic diseases, collected from 496 healthy children aged 5–17 years. In regression models age was the best single predictor of walking distance in younger age children, whereas anthropometrics were more important in girls and adolescents. Exercise heart rate was also an important distance predictor, in addition to age, and in most subgroups assessed outreached anthropometrics. Follow-up of children born very prematurely This is a major clinical issue, insofar as prematurity may result in long-term respiratory morbidity [18]. To address a specific problem related to prematurity, ORUC et al. [19] studied respiratory impedance using impulse oscillometry in 86 preschool children (aged 3–6 years) who were born with a very-low birth weight (<1500 g) and 40 term-born age-matched controls. Respiratory impedance testing disclosed bronchopulmonary dysplasia (BPD) in 43% of the preterm children. Although respiratory resistance was significantly higher and reactance was significantly lower in preterm children than in controls, these indices were not significantly different in preterm children without BPD and those with BPD, suggesting that lung function is impaired in preschool children born very prematurely even without a history of chronic lung disease. Addressing a similar problem, ZIVANOVIC et al. [20] assessed spirometry at 12–13 years in children born very prematurely (23–28 weeks of gestational age) from the UK Oscillation Study. They found that more males than females had reduced FEV1 (22% versus 3.5%; p=0.036), higher residual volume (34% versus 4%; p=0.009) and higher functional residual capacity (26% versus 0%; p=0.008), but these differences were not explained by greater airway hyperreactivity to cold air challenge (24% versus 26%; p=0.94). Physiological monitoring during sleep and in neuromuscular disease The evaluation of respiratory physiology in children with sleep disordered breathing or neuromuscular disease is also a very important topic for clinical practice. When studying the polysomnography data of 33 nonobese children aged 0.2–8 years, WONG et al. [21] found that children with trisomy 21 and pulmonary arterial hypertension (PAH) (n=6) had a significantly higher obstructive apnoea/hypopnoea index than those with PAH alone (n=9) or trisomy 21 without PAH (n=10) or children with neither trisomy 21 nor PAH (n=8) (p=0.01). These results suggest that children with both trisomy 21 and PAH are at increased risk of having obstructive sleep apnoea and should undergo sleep surveillance with polysomnography. Seeking more information on sleep disordered breathing, LOMAURO et al. [22] used optoelectronic plethysmography to study cough in 36 subjects with Duchenne muscular dystrophy (DMD) and 15 healthy controls during quiet breathing and maximal cough. The subjects' mean age was 16.3 years. In 15 children with DMD with inefficient cough (peak cough flow <160 L·min−1), thoracoabdominal asynchrony during cough (laboured breathing index) was higher and percentage abdominal contribution to tidal volume was lower than in controls or in those with efficient cough (n=9, peak cough flow >270 L·min−1). These data suggest that percentage abdominal contribution to tidal volume, a technique that does not require active collaboration, may be a useful tool for predicting inefficient cough in children with DMD.()，英语论文网站，英语论文 |
