BACKGROUND: The reflex zone stimulation technique (RST) activates complex motor responses and has a positive impact on the locomotor system. This technique may also indirectly affect breathing; however, the use of this technique as adjunct of the treatment of cystic fibrosis (CF) has not yet been characterised. METHODS: We performed a randomised controlled single-centre interventional trial to evaluate the short-term effects of RST on lung function in 21 paediatric CF patients with normal baseline spirometry. The effect of 30 min of RST was compared to that of sham therapy in a crossover design. The interventions were performed in random order and planned 6 months apart. The primary outcome was a change in global ventilation inhomogeneity after intervention, assessed by lung clearance index (LCI2.5 ) derived from a nitrogen multiple breath washout test. Secondary outcomes included changes in regional ventilation inhomogeneity (indices of acinar [Sacin*Vt] and conductive airway [Scond*Vt] inhomogeneity) and spirometry parameters (inspiratory capacity, forced vital capacity, and forced expiratory volume in 1 s). Trunk deformity was assessed by physiotherapists at study entry. RESULTS: After the RST intervention, the LCI2.5 (p = .004) and Scond*Vt (p = .009) decreased significantly, while inspiratory capacity increased (p = .012). In the sham-therapy group, none of the parameters changed significantly. Trunk deformity was seen in 76.5% of all patients, and 92.9% of those with trunk deformity showed a decrease in LCI2.5 after RST. CONCLUSION: RST has multiple positive short-term effects on lung function, especially in CF patients with trunk deformities.

• Klíčová slova
• cystic fibrosis, lung clearance index, lung function testing, reflex zone stimulation technique, ventilation inhomogeneity,
• MeSH
• cystická fibróza * terapie   MeSH
• dítě MeSH
• dýchání MeSH
• klinické křížové studie MeSH
• lidé MeSH
• plíce MeSH
• plicní ventilace MeSH
• reflex MeSH
• spirometrie MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH

BACKGROUND: Bronchial epithelial reticular basement membrane (RBM) thickening occurs in diseases with both eosinophilic (allergic bronchial asthma [BA]) and neutrophilic (cystic fibrosis [CF] and primary ciliary dyskinesia [PCD]) chronic airway inflammation; however, the lung function and airway remodeling relation remains unclear. The aim of this study was to test whether ventilation inhomogeneity is related to RBM thickening. METHODS: Multiple breath washout test, endobronchial biopsy, and BAL were performed in 24 children with CF, 11 with PCD, 15 with BA, and in 19 control subjects. Lung clearance index at 2.5% (1/40th) of starting nitrogen concentration (LCI2.5), RBM thickness, and lavage fluid cytology were quantified; their mutual associations were studied by using Spearman rank correlations (r). RESULTS: In asthma, ventilation inhomogeneity (mean ± SD) was mild (LCI2.5, 9.3 ± 1.4 vs 7.9 ± 0.9 in control subjects; P = .0391), and the RBM thickened (5.26 ± 0.98 μm vs 3.12 ± 0.62 μm in control subjects; P < .0001). No relation between RBM thickness and ventilation inhomogeneity or lavage cytology was found. In CF and PCD, RBM thickness was similar to that in asthma (4.54 ± 0.66 μm and 5.27 ± 1.11 μm, respectively), but ventilation inhomogeneity was significantly higher (LCI2.5, 12.5 ± 2.4 and 11.8 ± 2.5). Both in CF and PCD, RBM thickness correlated with LCI2.5 (r = 0.594, P = .015; r = 0.821, P = .023). In PCD only, RBM thickness was also related to the number of neutrophils in lavage fluid (r = 0.821; P = .023). CONCLUSIONS: Lung function impairment in relation to RBM thickness was milder in BA than in CF and PCD. In asthma, ventilation inhomogeneity did not correlate with RBM thickness, whereas it did in CF and PCD. This outcome suggests a different structure-function relation in these diseases.

• Klíčová slova
• airway remodeling, bronchial asthma, cystic fibrosis, multiple breath washout test, primary ciliary dyskinesia, reticular basement membrane thickening,
• MeSH
• bazální membrána patologie   MeSH
• biopsie metody   MeSH
• bronchiální astma * patologie   patofyziologie   MeSH
• bronchoalveolární lavážní tekutina MeSH
• bronchoskopie MeSH
• bronchy * patologie   patofyziologie   MeSH
• cystická fibróza * patologie   patofyziologie   MeSH
• dítě MeSH
• korelace dat MeSH
• lidé MeSH
• mukociliární clearance MeSH
• neutrofily patologie   MeSH
• plicní ventilace fyziologie   MeSH
• poruchy ciliární motility * patologie   patofyziologie   MeSH
• remodelace dýchacích cest MeSH
• respirační funkční testy metody   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Mechanical ventilation (MV) provides basic organ support for patients who have acute hypoxemic respiratory failure, with acute respiratory distress syndrome as the most severe form. The use of excessive ventilation forces can exacerbate the lung condition and lead to ventilator-induced lung injury (VILI); mechanical energy (ME) or power can characterize such forces applied during MV. The ME metric combines all MV parameters affecting the respiratory system (ie, lungs, chest, and airways) into a single value. Besides evaluating the overall ME, this parameter can be also related to patient-specific characteristics, such as lung compliance or patient weight, which can further improve the value of ME for characterizing the aggressiveness of lung ventilation. High ME is associated with poor outcomes and could be used as a prognostic parameter and indicator of the risk of VILI. ME is rarely determined in everyday practice because the calculations are complicated and based on multiple equations. Although low ME does not conclusively prevent the possibility of VILI (eg, due to the lung inhomogeneity and preexisting damage), individualization of MV settings considering ME appears to improve outcomes. This article aims to review the roles of bedside assessment of mechanical power, its relevance in mechanical ventilation, and its associations with treatment outcomes. In addition, we discuss methods for ME determination, aiming to propose the most suitable method for bedside application of the ME concept in everyday practice.

• MeSH
• agrese MeSH
• dýchání MeSH
• hrudník MeSH
• lidé MeSH
• poškození plic mechanickou ventilací * MeSH
• syndrom dechové tísně * MeSH
• umělé dýchání MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

• Klíčová slova
• infant, infant lung function, primary ciliary dyskinesia, ventilation inhomogeneity,
• MeSH
• cilie MeSH
• Kartagenerův syndrom * komplikace   MeSH
• kojenec MeSH
• lidé MeSH
• plíce MeSH
• poruchy ciliární motility * komplikace   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• Publikační typ
• dopisy MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH

Cave radon concentration measurements reflect the outcome of a perpetual competition which pitches flux against ventilation and radioactive decay. The mass balance equations used to model changes in radon concentration through time routinely treat flux as a constant. This mathematical simplification is acceptable as a first order approximation despite the fact that it sidesteps an intrinsic geological problem: the majority of radon entering a cavity is exhaled as a result of advection along crustal discontinuities whose motions are inhomogeneous in both time and space. In this paper the dynamic nature of flux is investigated and the results are used to predict cave radon concentration for successive iterations. The first part of our numerical modelling procedure focuses on calculating cave air flow velocity while the second part isolates flux in a mass balance equation to simulate real time dependence among the variables. It is then possible to use this information to deliver an expression for computing cave radon concentration for successive iterations. The dynamic variables in the numerical model are represented by the outer temperature, the inner temperature, and the radon concentration while the static variables are represented by the radioactive decay constant and a range of parameters related to geometry of the cavity. Input data were recorded at Driny Cave in the Little Carpathians Mountains of western Slovakia. Here the cave passages have developed along splays of the NE-SW striking Smolenice Fault and a series of transverse faults striking NW-SE. Independent experimental observations of fault slip are provided by three permanently installed mechanical extensometers. Our numerical modelling has revealed four important flux anomalies between January 2010 and August 2011. Each of these flux anomalies was preceded by conspicuous fault slip anomalies. The mathematical procedure outlined in this paper will help to improve our understanding of radon migration along crustal discontinuities and its subsequent exhalation into the atmosphere. Furthermore, as it is possible to supply the model with continuous data, future research will focus on establishing a series of underground monitoring sites with the aim of generating the first real time global radon flux maps.

• Klíčová slova
• Cave radon concentration, Cave radon flux, Cave ventilation, Fault slip, Numerical modelling, Radioactive decay,
• MeSH
• jeskyně * MeSH
• monitorování radiace MeSH
• pohyb vzduchu MeSH
• radioaktivní látky znečišťující vzduch analýza   MeSH
• radon analýza   MeSH
• teoretické modely * MeSH
• uzavřené prostory MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Slovenská republika MeSH
• Názvy látek
• radioaktivní látky znečišťující vzduch MeSH
• radon MeSH

Reticular basement membrane (RBM) thickening may occur in children with allergic bronchial asthma (BA), cystic fibrosis (CF), and primary ciliary dyskinesia (PCD). Its functional consequences remain unknown. We investigated the relationship between baseline RBM thickness and subsequent spirometry. In our cohort follow-up study, patients aged 3-18 yr with BA, CF, and PCD and controls underwent baseline lung clearance index (LCI) measurement, spirometry, and endobronchial biopsy sampling. Total RBM and collagen IV-positive layer thickness were measured. Trends in forced vital capacity (FVC), forced expired volume in 1 s (FEV1), and FEV1/FVC were analyzed during follow-up, and their relationship to baseline characteristics was studied using univariate analysis and multiple regression models. Complete baseline data were available in 19 patients with BA, 30 patients with CF, 25 patients with PCD, and 19 controls. The RBM was thicker in patients with BA (6.33 ± 1.22 μm), CF (5.60 ± 1.39 μm), and PCD (6.50 ± 1.87 μm) than in controls (3.29 ± 0.55 μm) (all P < 0.001). The LCI was higher in patients with CF (15.32 ± 4.58, P < 0.001) and PCD (10.97 ± 2.46, P = 0.002) than in controls (7.44 ± 0.43). The median follow-up times were 3.6, 4.8, 5.7, and 1.9 years in patients with BA, CF, PCD, and controls, respectively. The z-scores of FEV1 and FEV1/FVC deteriorated significantly in all groups except in controls. In patients with CF and PCD, trends in FEV1 z-scores correlated with baseline LCI and RBM; in BA, it correlated with collagen IV. In multiple regression models, RBM morphology and ventilation inhomogeneity could predict up to 84.4% of variability in spirometry trends. In conclusion, baseline LCI value and RBM morphology may predict trends in subsequent spirometry.NEW & NOTEWORTHY This paper deals with the relationship between reticular basement membrane (RBM) morphology at baseline and follow-up spirometry in children with asthma, cystic fibrosis, and primary ciliary dyskinesia. For the first time, to our knowledge, the possibility to predict subsequent lung function development using selected baseline characteristics (reticular basement membrane morphology from endobronchial biopsy and ventilation inhomogeneity from nitrogen multiple breath washout test) is proposed. Corresponding predictive models are presented.

• Klíčová slova
• airway remodeling, pediatric chronic airway inflammation, respiratory function tests, reticular basement membrane,
• MeSH
• bazální membrána patologie   MeSH
• bronchiální astma * patologie   MeSH
• cystická fibróza * patologie   MeSH
• dítě MeSH
• kolagen MeSH
• lidé MeSH
• následné studie MeSH
• plíce patologie   MeSH
• poruchy ciliární motility * MeSH
• spirometrie MeSH
• usilovný výdechový objem MeSH
• zánět patologie   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kolagen MeSH