Airway dynamics in COPD patients by within-breath impedance tracking: effects of continuous positive airway pressure.

Tracking of the within-breath changes of respiratory mechanics using the forced oscillation technique may provide outcomes that characterise the dynamic behaviour of the airways during normal breathing.We measured respiratory resistance (Rrs) and reactance (Xrs) at 8 Hz in 55 chronic obstructive pulmonary disease (COPD) patients and 20 healthy controls, and evaluated Rrs and Xrs as functions of gas flow (V') and volume (V) during normal breathing cycles. In 12 COPD patients, additional measurements were made at continuous positive airway pressure (CPAP) levels of 4, 8, 14 and 20 hPa.The Rrs and Xrsversus V' and V relationships displayed a variety of loop patterns, allowing characterisation of physiological and pathological processes. The main outcomes emerging from the within-breath analysis were the Xrsversus V loop area (AXV) quantifying expiratory flow limitation, and the tidal change in Xrs during inspiration (ΔXI) reflecting alteration in lung inhomogeneity in COPD. With increasing CPAP, AXV and ΔXI approached the normal ranges, although with a large variability between individuals, whereas mean Rrs remained unchanged.Within-breath tracking of Rrs and Xrs allows an improved assessment of expiratory flow limitation and functional inhomogeneity in COPD; thereby it may help identify the physiological phenotypes of COPD and determine the optimal level of respiratory support.

Exhaled breath condensate pH decreases during exercise-induced bronchoconstriction.

BACKGROUND AND OBJECTIVE: Exercise-induced bronchoconstriction (EIB) is the temporary narrowing of the airways caused by physical exercise. Its exact pathophysiology is unclear; however, acute changes in airways pH may play a role. Exhaled breath condensate (EBC) pH was suggested as a surrogate indicator for airway acid-base status, but its value is also affected by volatile molecules and respiratory droplet dilution. The aim of the study was to assess changes in EBC pH during EIB. METHODS: Twenty-two asthmatics who reported breathlessness following exercise and 16 healthy individuals participated in the study. Lung function test was performed and exhaled breath samples were collected for pH, dilution factor and volatile compound pattern measurements (Cyranose 320) pre-exercise and at 0, 10, 20 and 30 min after physical exercise challenge. Fractional exhaled nitric oxide was measured before exercise. RESULTS: EIB developed in 13 asthmatic subjects. In these participants, but not in the EIB-negative asthmatics (P = 0.51), EBC pH reduced significantly during exercise (P = 0.01). In addition, changes in EBC pH were related to the degree of bronchospasm in the EIB-positive group (P = 0.01, r = 0.68). Exhaled volatile pattern became altered (P < 0.05) during exercise in all subjects (asthmatics and controls). EBC pH changes were not related to EBC dilution or volatile compound pattern alterations (P > 0.05). CONCLUSIONS: The development of EIB was related to acute changes of EBC pH, which suggest the role of airway pH decrease in the pathophysiology of EIB. Exercise-induced changes in exhaled biomarkers suggest methodological precautions to avoid physical exercise before performing exhaled breath tests.

[Non-invasive respiratory unit in the Hungarian health care system]. / Nem invazív légzési osztály a hazai ellátórendszerben.

Treating patients with acute or chronic respiratory insufficiency still poses a major load on the healthcare system. Though there is evidence that treating these patients in high dependency respiratory units results in a shortening of hospital stay, reduces the need of intubation, and decreases mortality. In the Hungarian routine these patients are treated in general wards until the development of global respiratory insufficiency, when they are transferred to intensive care units. The authors present their first year experience on their novel Non-invasive Respiratory Unit established at Semmelweis University.

[The prevalence of melanocytic naevi among teenagers]. / A festéksejtes anyajegyek elofordulása tinédzsereken.

UNLABELLED: Malignant melanoma is an increasing public health problem worldwide; accordingly, identification of the constitutional and environmental factors which contribute to the development of the disease, and hence identification of the individuals at high risk of melanoma, are indispensable steps in all primary prevention efforts. AIM: The objective of the present study was to assess the prevalence of different pigmented lesions among schoolchildren, and to investigate their relationship with phenotypic pigmentary characteristics, sun exposure and other factors. METHODS: A cross-sectional study was performed in two secondary schools in Szeged, Hungary. A total of 1320 schoolchildren, aged 14 to 18 years, underwent a whole-body skin examination. A standardized questionnaire was used to collect data on phenotypic, sun exposure and other variables. RESULTS: Between 1-10 common melanocytic naevi were found in 27% of the participants, and naevi numbers were in the range between 10-100 in 67%. 5.4% of them had more than 100 common melanocytic naevi. The prevalence of clinically atypical naevi was 24.3%. Congenital naevi were detected in 6.2% of the schoolchildren. A statistically significant association was found between the number of pigmented lesions and gender, hair colour, eye colour, skin phototype, the history of severe painful sunburns, and the family history of a large number of melanocytic naevi. CONCLUSIONS: Our study population displayed a markedly high prevalence of clinically atypical melanocytic naevi. Moreover, a considerable proportion of the investigated individuals had multiple common melanocytic naevi. Since the presence of large number of melanocytic naevi is a strong predictor for future melanoma development, health educational programmes on melanoma prevention should be aimed at young age groups.