Real-life evaluation of NIV to CPAP switch in patients with chronic respiratory failure. A case control study.

Abstract

Background Non-invasive ventilation (NIV) is a standard of care for hypercapnic chronic respiratory failure (CRF). Obstructive sleep apnea (OSA) frequently contribute to hypoventilation in CRF. CPAP improves hypercapnia in selected COPD and obese patients. We describe the profile of patients switching from NIV to CPAP in a cohort of patients on long-term NIV and identify factors associated with a successful switch. Methods The observational research protocol evaluation committee of the French Pneumology Society approved this case-control study (CEPRO 2022-015). We compared 88 consecutive candidates for a NIV-CPAP switch with 266 controls among 394 ventilated patients treated at the Dijon University Hospital between 2015 and 2020. They followed a standardized protocol including a poly(somno)graphy recorded after NIV withdrawal for three nights. CPAP trial was performed if severe OSA was confirmed. Recurrent hypoventilation was checked after one night and one month under CPAP. Results Patients were 53% males, median age 65 [56–74] years, and median BMI 34 [25-38.5] kg/m2. Sixty seven percent of patients were safely switched and remained on CPAP. The probability of a NIV-CPAP switch was correlated to older age (OR:1.3 [1.01–1.06]), CRF etiology (OR for COPD:20.37 [4.2–98,72], obesity:7.31 [1.58–33.74]), circumstances of NIV initiation (OR for acute exacerbation:11.64 [2.03–66.62]), lower pressure support (OR:0.90 [0.73–0.92]), lower baseline PaCO2 (OR:0.85 [0.80–0.91]) and lower compliance (OR:0.76 [0.64–0.90]). Pressure support level was the only factor associated with the outcome of the NIV-CPAP switch. Conclusions A NIV-CPAP switch is possible in real life conditions in stable obese and COPD patients with underlying OSA.