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V Neve

Publications and source records attributed to V Neve.

8 recordsLinked to original sources

[Walking tests: a step forward for functional cardiorespiratory assessment].

Exercise testing provides information on physical capacity during exercise in addition to spirometric measures of lung function or assessment on treadmills or ergonomic cycle. The "gold standard" assessment of exercise tolerance is measured in the laboratory using treadmills or ergonomic cycle but the necessary equipment is expensive and may not be readily accessible; such tests require people used to work with children. Walking tests are field tests providing a valid and easily accessible method of measuring function-limited exercise tolerance in patients with respiratory or cardiac chronic diseases. These walking tests are non-threatening, inexpensive, easy to perform and to understand for children. Walking tests performed in daily practice are the following: "time-based" tests (2-, 6- or 12-min walking test), 3-min step test (on a step) and the shuttle walking test. It may be a useful measure to assess therapeutic intervention and provide information on the prognosis. They are simple and safe methods to evaluate quality of life in these patients.

Adolescent↗

Reproducibility of the respiratory dead space measurements in mechanically ventilated children using the CO2SMO monitor.

OBJECTIVES: To assess the reproducibility of respiratory dead space measurements in ventilated children. DESIGN: Prospective study. SETTING: University pediatric intensive care unit. PATIENTS: Thirty-two mechanically ventilated children (0.13-15.4 years) who were clinically stable. METHODS: The single-breath CO(2) test (SBT-CO(2)) was recorded using the CO(2)SMO Plus from the mean of 30 ventilatory cycles during 1 h (at T0, T15, T30, T45, and T60). Airway dead space was determined automatically (Novametrix Medical Systems, USA), and manually by Bohr- Enghoff equations using data obtained by SBT-CO(2). At the end of the study period, arterial blood gas was sampled in order to calculate alveolar and physiologic dead space. Intrasubject reproducibility of measurements was evaluated by the intraclass correlation coefficient. Two-way analysis of variance was used to evaluate the relationships between time and measurements. The two methods for calculating airway dead space were compared by using two-tailed Student's t-test and Bland-Altman analysis. RESULTS: Airway dead space measurement had a good reproducibility during the 1-h period, whatever the method used (intraclass correlation coefficient: 0.84 to 0.87). No significant difference was observed with time. Airway dead space values from the SBT-CO(2) method were smaller than those from Bohr-Enghoff equations. Physiologic dead space values from the SBT-CO2 method were similar to those from Bohr-Enghoff equations. CONCLUSION: The measurement of airway dead space by the CO(2)SMO Plus was reproducible over a 1-h period in children requiring mechanical ventilation, provided ventilatory parameters were constant throughout the study. SBT-CO(2) analysis may provide a bedside non-invasive monitoring of volumetric capnography.

Adolescent↗

[Reproducibility of the shuttle walk test in children with cystic fibrosis].

INTRODUCTION: Exercise testing is useful in the respiratory evaluation of patients with cystic fibrosis. The shuttle walk test (SWT) is a progressive, externally paced, exercise test requiring the subject to walk/run back and forth between two fixed points. The aim is to assess the reproductibility of the SWT in paediatric patients with cystic fibrosis. METHODS: This prospective study recruited 31 children with stable disease. The patients performed two SWT one day (SWT 1 and 2) and two others (SWT 3 and 4) within 15 days. Only SWT 2 and 4 were assessed for reproducibility. RESULTS: 61% were boys, median age (range): 12.9 (7-18.9) years, median Shwachman score (range): 80 (65-100), median values for FEV1 and FVC (range): 92 (55-154) and 92 (64-140)% predicted, respectively. Median distance for SWT 2-4 (range): 910 (580-1020) and 925 (540-1020) metres. Reproducibility for SWT distance and physical activity measured by an accelerometer is very good (intra-class correlation coefficient=0.90 and 0.92, respectively). SWT distance correlated with physical activity (p=3.10(-4)) and weight (p=0.03). SWT distance was independent of the following parameters: height, weight-for-age Z-score, FEV1, FVC, Shwachman score, colonisation with Pseudomonas aeruginosa. CONCLUSIONS: The SWT is reproducible in paediatric patients with cystic fibrosis and provides assessment of respiratory performance that complements spirometric measures of lung function.

Adolescent↗

Comparison of four methods for measuring elevation of FRC in mechanically ventilated infants.

The aim of the study was to compare measurements of the elevation of functional residual capacity (FRC) above the relaxation volume obtained in 34 mechanically ventilated infants (median weight 2.6 kg, range 1.2-9) from four different methods: (1) direct measurement of the complete exhalation volume after brief disconnection from the ventilator, (2) calculated measurement from total positive end-expiratory pressure (PEEP) measured by end-expiratory occlusion of the breathing circuit, (3) extrapolated evaluation from the mathematical model of Brody, (4) extrapolated evaluation from the passive expiration method. We considered the direct measurement (1) as the "gold standard". Measurements obtained by total PEEP (2) and by the Brody's mathematical model (3) provided similar results than the direct measurement. Conversely, graphical extrapolation from the passive expiration method (4) underestimated the elevation of FRC. In conclusion, we suggest using the mathematical extrapolation from the Brody's model to evaluate the elevation of FRC in mechanically ventilated infants: this method is non-invasive, does not require disruption of gas flow, can be easily performed with all the neonatal ventilators, and allows continuous breath-by-breath measurements.

Airway Resistance↗

[Isocapnic hyperventilation test adjusted to child's resting ventilation rate].

In order to validate an Isocapnic Voluntary Hyperventilation (IVH) test applicable to daily practice and to adapt the stimulus to height, 9 healthy and 15 asthmatic children performed a Resting Ventilation Rate (RVR)-corrected IVH. They performed a three-minute IVH with room temperature dry air achieving twice (IVH2) and three times (IVH3) their RVR. Mean Maximal Expiratory Flow (MEF) in the middle half of Forced Vital Capacity (FVC) (MEF25-75%) and mean MEF at 25% of FVC (MEF25%) are decreased in the asthmatic group 10 minutes IVH3 (p = 0.02 and < 0.002) compared to healthy group. Mean FEV1 of both group are not different. Comparing Forced Expiratory Flows variation after IVH to baseline intrasubject coefficient of variation, sensitivity of the test is 80% and specificity 100% when variations of MEF25-75% and MEF25% together with FEV1 variations are considered. This suggests an easy way to adapt an hyperventilation stimulus to size and emphasizes the utility of taking account of MEF25-75% and MEF25% in detecting non specific bronchial hyperreactivity in asthmatic children.

Adolescent↗

[Asthma in infants. Clinical and functional aspects].

BACKGROUND: The incidence of asthma in infancy is rising but its clinical and physiological components remain unclear. METHODS: A total of 24 infants, aged less than 48 months, in whom the first wheezing episode (WE) appeared before the age of 30 months (mean age: 9 months) underwent clinical examination and pulmonary function tests at least 2 weeks after the last WE. RESULTS: The mean WE frequency was 1.1 per month and the mean number of admissions for WE was 1.8. 63% of patients showed symptoms between WE and 50% had an allergic profile. There was no evidence of thoracic distension. Bronchial obstruction (BO) occurred in 71% of patients; among these, BO was distal or generalized in 59% and medium or severe in 47%. 12.5% of patients were hypoxemic at testing. BO was less severe in patients treated with theophylline; it was more frequent (87%) in those with symptoms between WE and/or several admissions, and/or admission to the intensive care unit. CONCLUSION: This study provides additional evidence that infants presenting with asthma at an early age have severe clinical and physiological profiles.

Age Factors↗

[Development of a multiple PCR method for the identification of Ureaplasma parvum and Ureaplasma urealyticum].

Ureaplasma parvum and Ureaplasma urealyticum, also known as biovar parvum and biovar T960, respectively, could be associated with several disorders in men, women, and mainly, in newborn children with under weight. Several methods have been developed in order to identify the species or biovars of ureaplasmas. We developed a Multiplex-PCR method using the UPS-UPSA and UUS2-UUA2 primers, specific for U. parvum and U. urealyticum, respectively. This Multiplex-PCR method was used to identify cultures of clinical positive samples to Ureaplasma spp. by the "MYCOFAST Evolution-2" Kit. Of 56 positive cultures to Ureaplasma spp. from newborn children, 70% were U. parvum and 30% U. urealyticum; in 76 positive samples in women, 83% corresponded to U. parvum and 17% to U. urealyticum, while in 63 positive samples of men, 76% identified U. parvum and 24% U. urealyticum. The PCR-multiplex method showed specificity for the identification of the biovars or species of ureaplasmas of clinical interest.

Adult↗