Clinical Research Directory

INSPIRatory Efforts Estimation Under High-flow Nasal Oxygen

High-flow nasal oxygen (HFNO) is recommended as first-line treatment to prevent intubation in acute hypoxemic respiratory failure and to prevent reintubation after extubation. Accumulating data suggest that strong inspiratory efforts and their persistence are associated with HFNO failure. However, tools to monitor continuously and noninvasively inspiratory efforts are lacking. The investigators have developed an algorithm estimating noninvasively inspiratory efforts under HFNO. This pilot study aims at testing the feasibility of estimating inspiratory efforts in patients treated with HNFO.

The Role of Environmental Temperatures in Respiratory Control

Warfighters are frequently exposed to environments and life-support systems that increase breathing resistance and the work of breathing (WOB), such as aircraft on-board oxygen generation systems and underwater breathing apparatuses. Elevated WOB increases the perception of breathing difficulty (dyspnea) and has been associated with impaired cognitive performance, including slower reaction time and reduced accuracy during attention-demanding tasks. These effects are particularly concerning in operational settings that require rapid decision-making and precise motor responses. Despite growing recognition of this issue, critical gaps remain regarding strategies to mitigate the perceptual and cognitive consequences of elevated inspiratory resistance, especially under realistic operational stressors. The objective of this study is to determine whether exposing individuals to thermal stress alters breathing perception and cognitive performance during inspiratory resistance. Participants will perform inspiratory resistance breathing under thermoneutral, heat, and cold conditions to determine whether thermal stress amplifies WOB, breathing perception, and cognitive impairment.

The Role of Breathing Perception in Respiratory Control

Warfighters are frequently exposed to environments and life-support systems that increase breathing resistance and the work of breathing (WOB), such as aircraft on-board oxygen generation systems and underwater breathing apparatuses. Elevated WOB then increases the perception of breathing difficulty (dyspnea) and has been associated with impaired cognitive performance, including slower reaction time and reduced accuracy during attention-demanding tasks. These effects are particularly concerning in operational settings that require rapid decision-making and precise motor responses. Despite growing recognition of this issue, critical gaps remain regarding strategies to mitigate the perceptual and cognitive consequences of elevated inspiratory resistance, especially under realistic operational stressors. The objective of this experiment is to determine whether modifying the sensory perception of breathing alters breathing perception and cognitive performance during inspiratory resistance. Auditory feedback of ventilation will be manipulated (normal, reduced, or amplified) to assess whether altering breathing-related sensory input affects breathing perception and cognitive performance without changing mechanical load.

The Role of Heliox in Respiratory Control

Warfighters are frequently exposed to environments and life-support systems that increase breathing resistance and the work of breathing (WOB), such as aircraft on-board oxygen generation systems and underwater breathing apparatuses. Elevated WOB increases the perception of breathing difficulty (dyspnea) and has been associated with impaired cognitive performance, including slower reaction time and reduced accuracy during attention-demanding tasks. These effects are particularly concerning in operational settings that require rapid decision-making and precise motor responses. Despite growing recognition of this issue, critical gaps remain regarding strategies to mitigate the perceptual and cognitive consequences of elevated inspiratory resistance, especially under realistic operational stressors. The objective of this study is to determine whether reducing mechanical WOB alters breathing perception and cognitive performance during inspiratory resistance. Participants will breathe either normal-density air or a low-density helium-oxygen gas mixture (heliox) to determine whether reducing mechanical WOB lowers perceived breathing effort and improves cognitive function.

Electrical Activity of the Diaphragm and Respiratory Mechanics During NAVA

Protective ventilatory strategy should be applied to reduce ventilator-induced lung injury (VILI) after Lung Transplantation (LTx) or in case of acute respiratory failure requiring invasive mechanical ventilation. Neurally Adjusted Ventilatory Assist (NAVA) is an assisted ventilation mode in which respiratory support is coordinated by the electrical activity of the diaphragm (EAdi). Aim of the study is to assess the physiological relationship between neural respiratory drive, as assessed by EAdi, and tidal volume, driving pressure, and mechanical power, at different levels of ventilatory assist, in the absence of pulmonary vagal afferent feedback or during acute respiratory failure. Additional parameters will be collected: Pmus, Pocc, transpulmonary pressure etc.

Proportional Assist Ventilation Plus and Estimation of Respiratory Effort During the Transition to Spontaneous Ventilation

In intensive care units, many critically ill patients need help from a machine called a ventilator to breathe. Once these patients start to recover, doctors try to gradually reduce this support and help them breathe on their own again. However, not all patients are ready to be taken off the ventilator right away. During this transition, it's important to find the right amount of help-enough to support their breathing, but not so much that the machine does all the work for them. This study focuses on a special type of ventilator setting called Proportional Assist Ventilation Plus (PAV+). Unlike traditional modes, which give a fixed level of support, PAV+ adjusts the amount of help it gives based on how hard the patient is trying to breathe. The more effort a patient makes, the more support the machine provides-and vice versa. This can make breathing feel more natural and may protect the lungs and breathing muscles during recovery. Modern ventilators also display a measurement called "Work of Breathing," which tells how much effort the patient is using to breathe. This study wants to find out whether this measurement from the ventilator is a reliable way to monitor a patient's breathing effort, compared to other more invasive or complex methods. The research will include 20 adult patients who are recovering in the ICU and have been on mechanical ventilation for more than 48 hours. All patients will have already met some criteria showing they're ready to begin breathing more on their own, but are not quite ready to have the breathing tube removed. Each patient will go through different levels of PAV+ support, and researchers will record how much effort they make to breathe using several methods, including special pressure sensors and data from the ventilator. The goal of the study is to better understand how to measure breathing effort safely and easily, and to improve how we support patients as they recover the ability to breathe on their own. If successful, this could help reduce complications and improve recovery for people on ventilators. There are no added risks or costs for the patients involved. All equipment used in the study is already part of regular ICU care. Participation requires informed consent and the privacy of all participants will be fully protected.