Long term noninvasive ventilation in the Geneva Lake area: indications, prevalence and modalities

Abstract Background Noninvasive ventilation (NIV) is standard of care for chronic hypercapnic respiratory failure but indications, devices and ventilatory modes are in constant evolution. Research question To describe changes in prevalence, and indications for NIV over a 15 year period; to provide a comprehensive report of characteristics of the population treated (age, comorbidities, anthropometric data), mode of implementation and follow-up, devices, modes and settings used, physiological data, compliance, and data from ventilator software. Design cross-sectional observational study, designed to include all subjects under NIV followed by all structures involved in NIV in the Cantons of Geneva and Vaud (1'288'378 inhabitants) Results 489 patients under NIV were included. Prevalence increased 2.5-fold since 2000 reaching 38/105 inhabitants. Median age was 71 years, 31% being over 75. Patients had been under NIV for a median of 39 months, had an average of 3±1.8. comorbidities; 55% were obese. COPD (including overlap syndrome) was the most important patient group, followed by obesity -hypoventilation (OHS, 26%). Daytime PaCO2 was most often normalized; adherence to treatment was satisfactory, with 8% only using their device less than 03:30 hours/day. Bi-level positive pressure ventilators in ST mode was the default mode (86%), with a low use of auto-titrating modes. NIV was initiated electively in 50% of the population, in a hospital setting form 82%, and as outpatients for 15%. Interpretation Use of NIV is increasing rapidly in this area, and the population treated is aging, comorbid, frequently obese. COPD is presently the leading indication followed by OHS.