Impact of Humidification on Sleep Quality During Home Non Invasive Ventilation

Protocol Summary:

1. Question Does the adjunction of a humidification system to non-invasive ventilation circuit improve sleep quality and comfort of chronic ventilated respiratory insufficient patients? Does it change the efficacy of long-term non invasive ventilation therapy and patient-ventilator interactions? 2. Aims

Main aim:

The primary endpoint of this study is to objectively evaluate the consequences of a humidification system's adjunction on quality of sleep, 2 months after treatment's beginning.

Second aims:

The secondary endpoints are to evaluate the consequences of a humidification system's adjunction on non invasive ventilation's efficacy / patient-ventilator asynchronies / patients' comfort / treatment adherence.

Before the clinical trial, the investigators conducted a bench study using a mechanical lung in order to evaluate the ventilator's behavior with and without a humidification system.

The clinical trial will include patients with chronic respiratory failure with an indication of long-term non invasive ventilation therapy. Patients will be included in the Pulmonology, Thoracic Oncology and Respiratory intensive care unit of Rouen University Hospital.

It will be a prospective monocentric study, including consecutively all eligible patients. Informed consent will be obtained from all of them.

At baseline, patients will be hospitalized for two consecutive nights for non invasive ventilation's set up. During the first night, a polysomnography will be performed without non invasive ventilation. Then, patients will be treated by non invasive ventilation with a bi-level self-regulated pressure mode and an open circuit.

Patients will be randomized in two groups: without a humidification system and with a humidification system. Partitioning by the physiopathological pattern (obstructive versus obesity hypoventilation syndrome vs. neuromuscular disease) will be done.

During each night, arterial blood gases will be measured at bedtime and awakening. Patients will be monitored by:

* polysomnography (only during the first night) * transcutaneous capnography * accessory inspiratory muscles surface electromyography * pneumotachograph on non invasive ventilation's circuit * pressions measured at the mask.

Follow-up will take place at two months after non invasive ventilation's beginning with or without humidification. Patients will be hospitalized for one night only. Blood gases at bedtime and at awakening will be measured. A polysomnography with non invasive ventilation will be performed. Observance will be evaluated.