Evaluation of Breathing Effort in Spontaneously Breathing Subjects

The aim of the research project is to evaluate the breathing effort using the Work of Breathing (WoB) and Pressure-Time Product (PTP) parameters, depending on the increasing flow resistance. The research project is concerned with assessing the increased (imposed) breathing effort using the Work of Breathing (iWoB) and the Pressure-Time Product (iPTP). The main hypothesis tested is the differential effect of flow resistance on iWoB and iPTP parameters in spontaneous breathing of healthy probands.

Due to the different calculation of iWoB and iWoB, these parameters may be affected at higher flow resistance values. The proposed experiment will be used to compare iWoB and iPTP obtained during spontaneous breathing to healthy subjects.

In the experiment, the proband will breathe through the D-Lite measuring screen of the Datex-Ohmeda S/5 Patient Monitor patient monitor (GE, USA). Unlike clinical practice, an adjustable flow resistance will be connected to the system. The flow resistance is set by adjustable by a removable diaphragm with different hole diameters according to the intended flow resistance.

During the experiment, the volunteers will breathe through ten adjustable flow resistances and their work of breathing will be measured.

The proband will breathe through the adjustable flow resistance within the experiment, to which a standard D-lite Flow sensor will be connected, and the airway pressure, flow, minute consumption, oxygen and carbon dioxide, tidal volume, oxygen saturation of peripheral blood and oxygen and carbon dioxide concentrations in both inspired and expired air will be recorded using the Datex-Ohmeda S/5 Patient Monitor vital signs monitor. The proband will breathe through the flow resistors in a randomized order, and pre-defined three-minute pauses will be maintained between measurements with different flow resistance values. Each measurement will take approximately two minutes and will be measured on ten different flow resistances.

Inclusion Criteria: Healthy males and females > 18 and < 40 years old Signed informed consent has been obtained Exclusion Criteria: Respiratory disease Pregnancy Cardiovascular disease Diabetes mellitus

Department of Biomedical Technology Faculty of Biomedical Engineering Czech Technical University in Prague

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