Background: Noninvasive ventilation (NIV) is intented to correct alveolar hypoventilation in patients with chronic hypercapnic respiratory failure (CHRF). A French telemedicine experiment (ETAPES, 2018-2022) including NIV daily telemonitoring and therapeutic education aimed to improve patient pathways and costs. Telemonitoring alerts were generated in case of low NIV use, high leaks or change in respiratory rate or NIV use. eVENT compared the correction of hypercapnia after 6 months of ETAPES telemonitoring (ETM) or usual follow-up (UF).

Methods: Patients having started NIV for less than 2 months and fulfilling ETAPES eligibility criteria were randomized 1:1 in 2021-2022 to ETM or UF in a multicenter trial. The primary outcome was mean nocturnal PtCO2 at 6 months. One secondary outcome was room air PaCO2 at 6 months.

Results: 53 patients (ITT, 29F/24M; 66±13 years) were equally distributed in both groups. CHRF was mainly related to COPD (n=23, FEV1 43±17%pred) and OHS (n=24; BMI 42±12 Kg/m2). Mean PaCO2 at NIV initiation was 52±6 mmHg. After 6 months, mean PtCO2 was 42.1±6.1 mmHg in ETM (n=23) and 43.9±6.4 in UF (n=23)(p=0.35). Two patients (9%) in ETM vs 4 (17%) in UF had a persistent nocturnal hypercapnia (mean PtCO2>50). PaCO2 was 41.7±6.8 mmHg in ETM (n=23) and 46.2±3.5 in UF (n=19)(p=0.003). Twenty (87%) patients had their PaCO2 normalized or reduced by at least 20% compared to baseline in ETM, vs 7 (37%) in UF (p=0.001).

Conclusion: A higher proportion of patients without diurnal or nocturnal hypoventilation is seen with ETM (n=19, 83%) than UF (n=6, 27%) at 6 months (p<0.001).