[Measuring breathing pattern in patients with chronic obstructive pulmonary disease by electrical impedance tomography].

Background And Objective: The measurement of breathing pattern in patients with chronic obstructive pulmonary disease (COPD) by electrical impedance tomography (EIT) requires the use of a mathematical calibration model incorporating not only anthropometric characteristics (previously evaluated in healthy individuals) but probably functional alterations associated with COPD as well. The aim of this study was to analyze the association between EIT measurements and spirometry parameters, static lung volumes, and carbon monoxide diffusing capacity (DLCO) in a group of male patients to develop a calibration equation for converting EIT signals into volume signals.

Materials And Methods: We measured forced vital capacity (FVC), forced expiratory volume in 1 second (FEV(1)), FEV(1)/FVC, residual volume, total lung capacity, DLCO, carbon monoxide transfer coefficient (KCO) and standard anthropometric parameters in 28 patients with a FEV(1)/FVC ratio of <70%.

[Bilateral dorsal sympathectomy for the treatment of primary hyperhidrosis: effects on lung function at 3 years].

Introduction: Primary hyperhidrosis is characterized by excessive sweating of the palms, soles, and axillae due to overactivity of the sympathetic nervous system at the level of the second and third sympathetic thoracic ganglia. The treatment of choice is bilateral dorsal sympathectomy performed using video-assisted thoracic surgery (VATS). The objective of our study was to determine whether lung function changes observed in a group of patients prior to bilateral dorsal sympathectomy performed using VATS were still evident 3 years after surgery.

[Determining the alveolar component of nitric oxide in exhaled air: procedures and reference values for healthy persons].

Nitric oxide (NO) production has been described using a 2-compartment model for the synthesis and movement of NO in both the alveoli and the airways. The alveolar concentration of NO (Ca(NO)), an indirect marker of the inflammatory state of the distal portions of the lung, can be deduced through exhalation at multiple flow rates. Our objective was to determine reference values for Ca(NO).

Duration of pulmonary rehabilitation to achieve a plateau in quality of life and walk test in COPD.

Objective: To address the minimum duration of pulmonary rehabilitation necessary for patients with chronic obstructive pulmonary disease (COPD) to achieve a plateau in Health-Related Quality of Life (HRQL) and exercise tolerance.

Methods: COPD patients with a dyspnea rating of at least 2 on the Medical Research Council scale participated in an outpatient rehabilitation program of 3 weekly sessions for 12 weeks. Measurements included HRQL and exercise tolerance 2 weeks before the program started and every 2 weeks thereafter.

[Assessment of differential lung function by electrical impedance tomography].

Objective: To compare unilateral lung function estimated by 2 methods: electrical impedance tomography (EIT) and ventilation-perfusion lung scintigraphy.

Patients And Methods: This prospective clinical study was carried out in the pulmonary function laboratory of a general hospital. Twenty patients diagnosed with lung cancer (17 men and 3 women, ranging in age from 25 to 77 years) who were candidates for lung resection underwent ventilation-perfusion lung scanning breathing a radioactive gas.

Diagnostic utility of inflammatory biomarkers in asthma: exhaled nitric oxide and induced sputum eosinophil count.

Background: Even though an inflammatory process is known to be the underlying cause of asthma, diagnosis is based on clinical history, reversible airway obstruction and bronchial hyperresponsiveness according to international guidelines. The fraction of exhaled nitric oxide (FE(NO)) and induced sputum eosinophil count (Eos%) have been used as non-invasive inflammatory biomarkers.

Objectives: The aim of this study was to compare the sensitivity and specificity of FE(NO), Eos% and spirometry and to assess whether their combined use in clinical practice would improve diagnostic yield.

[Monitoring of breathing pattern at rest by electrical impedance tomography].

Objective: Electrical impedance tomography (EIT) involves the application of a small alternating current to produce a series of chest images that can be used to monitor breathing pattern. The relation between chest images and tidal volume has not been sufficiently validated. The aim of the present study was to analyze the correlation between EIT images and the volume-time signal measured with a pneumotachometer in 13 healthy volunteers.

[Measurement of fraction of exhaled nitric oxide with the portable NIOX-MINO monitor in healthy adults].

Measurement of the fraction of exhaled nitric oxide (FENO) provides a noninvasive way to monitor asthma treatment in clinical practice. The aim of this study was to determine FENO reference values for measurements recorded with the portable NIOX MINO monitor in a group of healthy volunteers. We also assessed the association between values recorded by the portable monitor and the N-6008 chemiluminescence analyzer used in our pulmonary function laboratory.

Use of electrical impedance tomography (EIT) for the assessment of unilateral pulmonary function.

We describe a fully automatable quantification process for the assessment of unilateral pulmonary function (UPF) by means of EIT and propose a measurement protocol for its clinical implementation. Measurements were performed at the fourth and sixth intercostal levels on a first group of ten healthy subjects (5M, 5F, ages 26-48 years) to define the proper protocol by evaluating the most common postures and ventilation modes. Several off-line processing tools were also evaluated, including the use of digital filters to extract the respiratory components from EIT time series.