Non-invasive ventilation (NIV) is the reference treatment for chronic respiratory failure (CRF) due to impairment of the ventilatory system. Home initiation is increasingly practiced. To better support this ambulatory shift, we aimed to assess the implementation constraints and short-term efficacy according to different aetiologies of CRF.

This retrospective study with cross-sectional and longitudinal analysis included patients initiated with NIV at Angers University Hospital. Patients were separated according to the following aetiologies: obesity hypoventilation syndrome (OHS), chronic obstruction pulmonary disease (COPD), amyotrophic lateral sclerosis (ALS), myopathy and chest wall disease. Implementation constraints were assessed by analysing the variability of NIV settings, the number of masks tried and the duration of hospitalisation. NIV effectiveness was assessed by measuring residual PaCO2 (arterial pressure in CO2), apnoea hypopnea index (AHI_flow) and tidal volume (V_T) (as displayed by the NIV software).

Between October 2020 and May 2022, 102 patients were started with NIV, including a majority of ALS patients. We found a moderate variability in NIV settings (pressure, slope, triggers, etc.) within the different etiological groups, particularly in ALS. On the other hand, ALS patients required more interface trials than other groups and often had unmet efficacy criteria at hospital discharge. Interestingly, longitudinal follow-up showed a progressive improvement in efficacy criteria, particularly in patients who were initially inadequately ventilated.

Each aetiological group has specific constraints in the initiation of NIV that should be considered when initiating NIV in the outpatient setting.