PAOLO JOSE CESARE BISELLI
Projetos de Pesquisa
Unidades Organizacionais
SCPACIN-62, Hospital Universitário
4 resultados
Resultados de Busca
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- Nonlinear Flow Sensor Calibration with an Accurate Syringe(2018) BISELLI, Paolo Jose Cesare; NOBREGA, Raquel Siqueira; SORIANO, Francisco GarciaFlow sensors are required for monitoring patients on mechanical ventilation and in respiratory research. Proper calibration is important for ensuring accuracy and can be done with a precision syringe. This procedure, however, becomes complex for nonlinear flow sensors, which are commonly used. The objective of the present work was to develop an algorithm to allow the calibration of nonlinear flow sensors using an accurate syringe. We first noticed that a power law equation could properly fit the pressure-flow relationship of nonlinear flow sensors. We then developed a software code to estimate the parameters for this equation using a 3 L syringe (calibration syringe). Finally, we tested the performance of a calibrated flow sensor using a different 3 L syringe (testing syringe) and a commercially available spirometer. After calibration, the sensor had a bias ranging from -1.7% to 3.0% and precision from 0.012 L to 0.039 L for volumes measured with the 3 L testing syringe. Calibrated sensor performance was at least as good as the commercial sensor. This calibration procedure can be done at the bedside for both clinical and research purposes, therefore improving the accuracy of nonlinear flow sensors.
- Nasal high flow, but not supplemental O-2, reduces peripheral vascular sympathetic activity during sleep in COPD patients(2018) FRICKE, K.; SCHNEIDER, H.; BISELLI, P.; HANSEL, N. N.; ZHANG, Z. G.; SOWHO, M. O.; GROTE, L.Introduction: Patients with COPD have increased respiratory loads and altered blood gases, both of which affect vascular function and sympathetic activity. Sleep, particularly rapid eye movement (REM) sleep, is known to exacerbate hypoxia and respiratory loads. Therefore, we hypothesize that nasal high flow (NHF), which lowers ventilatory loads, reduces sympathetic activity during sleep and that this effect depends on COPD severity. Methods: We performed full polysomnography in COPD patients (n=17; FEV1, 1.6 +/- 0.6 L) and in matched controls (n=8). Participants received room air (RA) at baseline and single night treatment with O-2 (2 L/min) and NHF (20 L/min) in a random order. Finger pulse wave amplitude (PWA), a measure of vascular sympathetic tone, was assessed by photoplethysmography. Autonomic activation (AA) events were defined as PWA attenuation >= 30% and indexed per hour for sleep stages (AA index [AAI]) at RA, NHF, and O-2). Results: In COPD, sleep apnea improved following O-2 (REM-apnea hypopnea index [AHI] with RA, O-2, and NHF: 18.6 +/- 20.9, 12.7 +/- 18.1, and 14.4 +/- 19.8, respectively; P=0.04 for O-2 and P=0.06 for NHF). REM-AAI was reduced only following NHF in COPD patients (AAI-RA, 21.5 +/- 18.4 n/h and AAI-NHF, 9.9 +/- 6.8 n/h, P=0.02) without changes following O-2 (NFIF-O-2 difference, P=0.01). REM-AAI reduction was associated with lung function expressed as FEV1 and FVC (FEV1: r=-0.59, P=0.001; FEV1/FVC: r=-0.52 and P=0.007). Conclusion: NHF but not elevated oxygenation reduces peripheral vascular sympathetic activity in COPD patients during REM sleep. Sympathetic off-loading by NHF, possibly related to improved breathing mechanics, showed a strong association with COPD severity.
- Lung Mechanics Over the Century: From Bench to Bedside and Back to Bench(2022) BISELLI, Paolo Jose Cesare; LOPES, Fernanda Degobbi Tenorio Quirino Dos Santos; RIGHETTI, Renato Fraga; MORIYA, Henrique Takachi; TIBERIO, Iolanda Ftima Lopes Calvo; MARTINS, Milton ArrudaLung physiology research advanced significantly over the last 100 years. Respiratory mechanics applied to animal models of lung disease extended the knowledge of the workings of respiratory system. In human research, a better understanding of respiratory mechanics has contributed to development of mechanical ventilators. In this review, we explore the use of respiratory mechanics in basic science to investigate asthma and chronic obstructive pulmonary disease (COPD). We also discuss the use of lung mechanics in clinical care and its role on the development of modern mechanical ventilators. Additionally, we analyse some bench-developed technologies that are not in widespread use in the present but can become part of the clinical arsenal in the future. Finally, we explore some of the difficult questions that intensive care doctors still face when managing respiratory failure. Bringing back these questions to bench can help to solve them. Interaction between basic and translational science and human subject investigation can be very rewarding, as in the conceptualization of ""Lung Protective Ventilation"" principles. We expect this interaction to expand further generating new treatments and managing strategies for patients with respiratory disease.
- Analysis of respiratory mechanics in animal models: Its use in understanding lung behavior in emphysema and asthma(2019) BISELLI, P.J.C.; KOHLER, J. Benini; RIGHETTI, R.; TIBéRIO, I. de Fátima Lopes Calvo; MARTINS, M. de Arruda; LOPES, F. Degobbi Tenorio Quirino dos SantosRespiratory mechanics assessment in animal models of respiratory diseases is considered a reliable tool to understand how structural changes impact lung function. Mathematical models, such as the equation of motion and the constant-phase model are used to describe the properties of the respiratory system. The equation of motion is valued because it is relatively simple to apply and describes the respiratory systems with few parameters. The constant-phase model is more complex but provides more detailed information about different lung compartments. In this review, we summarize how respiratory mechanics have been used to describe lung behavior as well as how these measurements reflect the progression of structural changes caused by emphysema and asthma in animal models. © 2019 Elsevier Ltd