Sensory and Emotional Modulation of Dyspnea Under Artificial Ventilation in the Intensive Care Unit

Rationale: Half of the patients receiving mechanical ventilation in the intensive care unit (ICU) have moderate to severe dyspnea. This dyspnea has a negative impact on the duration of mechanical ventilation, on patients' comfort and could be involved in the genesis of post-traumatic stress syndromes, a frequent complication of intensive care. Modifying ventilation parameters does not always relieve dyspnea and administering morphine prolongs the duration of mechanical ventilation. Dyspnea has, in addition to its sensory component, an emotional component. The possibility to distract the patients' attention or to modulate their emotions in order to relieve their dyspnea could therefore represent an innovative therapeutic alternative devoid of side effects. Objectives: To evaluate the effect of auditory and sensory extra respiratory stimuli on the sensation of dyspnea in intensive care patients undergoing mechanical, invasive or non-invasive ventilation. Methods: 45 intensive care patients under artificial ventilation will be exposed, according to their randomization arm, to the following two stimuli for a duration of 10 minutes: * standard relaxing music piece versus "pink" noise; * fresh air on the face versus fresh air on the thigh. The effect of this stimulus will be compared to a randomized control, these two conditions will be separated by a wash-out period. An pressure support (+5) increment will be performed to ensure comparability of subsequent experimental sequences and their effect on dyspnea. Dyspnea will be assessed in terms of intensity (visual analog scale) and characterized sensorially. Will also be evaluated during the different conditions: pain, anxiety and stress (sympathetic/parasympathetic balance) and extra-diaphragmatic electromyographic activity. Ethical framework: research involving the human person at risk and minimal constraints (physiology study that does not entail any risk for the patients). Expected results and prospects: the inve