Validation of an Observational Scale of Dyspnea in Non-communicating Patients in the ICU

Background : Dyspnea is common and severely impact mechanically ventilated patients outcomes in intensive care unit (ICU). Recognize, measure and treat dyspnea have become current major therapeutic challenge. Its measurement involves a self-assessment by the patient, and by definition, a certain level of communication. Consequently, a large proportion of the ICU-population (non-communicating) misses its evaluation and potential benefits associated with its control. In other hand, electrophysiological markers that help to detect and quantify dyspnea regardless of the patient's cooperation, has been developed and validated as dyspnea surrogate, namely: 1) the electromyographic (EMG) activity of extra diaphragmatic inspiratory muscles and 2) the premotor inspiratory potentials (PIP) detected on the electroencephalogram (EEG). Because of its complex implementation in daily practice the research team has developed alternatively a behavioral score called IC-RDOS that provides reliable dyspnea assessment also without patient participation. Validated in conscious patients, it has not been yet validated in non-communicating patients. Hypothesis : The IC-RDOS is valid for non-communicating ventilated patients and allows a simple and reliable assessment of dyspnea in this specific population. Objective : To validate the IC-RDOS in non-communicating ICU patients under mechanical ventilation, using comparison with the tools validated for reliable measure of dyspnea in non-communicating patients (EMG, EEG). Patients and Methods: In 40 patients will be collected simultaneously IC-RDOS, PIP (EEG) and electromyographic activity of three extra diaphragmatic inspiratory muscles (scalene, parasternal and Alae nasi) before and after intervention therapy aiming at reduce dyspnea (ventilator settings or pharmacological intervention), initiated by the clinician in charge of the patient. Expected results : Observe a strong positive correlation between the IC-RDOS and electrophysiologica