Auto-adjusted versus fixed positive airway pressure in patients with severe OSA: A large randomized controlled trial.

BACKGROUND AND OBJECTIVE: Continuous positive airway pressure (CPAP) in the treatment of severe obstructive sleep apnoea (OSA) can be used in fixed CPAP or auto-adjusted (APAP) mode. The aim of this prospective randomized controlled clinical study was to evaluate the 3 month-efficacy of CPAP used either in fixed CPAP or APAP mode. METHODS: Eight hundred one patients with severe OSA were included in twenty-two French centres. After 7 days during which all patients were treated with APAP to determine the effective pressure level and its variability, 353 and 351 patients were respectively randomized in the fixed CPAP group and APAP group. After 3 months of treatment, 308 patients in each group were analysed. RESULTS: There was no difference between the two groups in terms of efficacy whatever the level of efficient pressure and pressure variability (p = 0.41). Exactly, 219 of 308 patients (71.1%) in the fixed CPAP group and 212 of 308 (68.8%) in the APAP group (p = 0.49) demonstrated residual apnoea hypopnoea index (AHI) <10/h and Epworth Score <11. Tolerance and adherence were also identical with a similar effect on quality of life and blood pressure evaluation. CONCLUSION: The two CPAP modes, fixed CPAP and APAP, were equally effective and tolerated in severe OSA patients.

Mid-term pulmonary sequelae after hospitalisation for COVID-19: The French SISCOVID cohort.

BACKGROUND: Even though COVID-19 clinical features, pathogenesis, complications, and therapeutic options have been largely described in the literature, long-term consequences in patients remain poorly known. METHODS: The French, multicentre, non-interventional SISCOVID study evaluated lung impairment three (M3) and six months (M6) after hospital discharge in patients recovered from COVID-19. Evaluation was based on clinical examination, pulmonary function tests, and chest computed tomography (CT-scan). RESULTS: Of the 320 included patients (mean age: 61 years; men: 64.1%), 205 had had a severe form of COVID-19, being hospitalised in an intensive care unit (ICU), and requiring high flow nasal cannula, non-invasive ventilation, or invasive mechanical ventilation. At M6, 54.1% of included patients had persistent dyspnoea (mMRC score ≥1), 20.1% severe impairment in gas diffusing capacity (DLCO <60% pred.), 21.6% restrictive ventilatory pattern (total lung capacity <80% pred.), and 40% a fibrotic-like pattern at CT-scan. Fibrotic-like pattern and restrictive ventilatory pattern were significantly more frequent in patients recovered from severe than non-severe COVID-19. Improved functional and radiological outcomes were observed between M3 and M6. At M6, age was an independent risk factor for severe DLco impairment and fibrotic-like pattern and severe COVID-19 form was independent risk factor for restrictive ventilatory profile and fibrotic-like pattern. CONCLUSION: Six months after discharge, patients hospitalised for COVID-19, especially those recovered from a severe form of COVID-19, frequently presented persistent dyspnoea, lung function impairment, and persistent fibrotic-like pattern, confirming the need for long-term post-discharge follow-up in these patients and for further studies to better understand long-term COVID-19 lung impairment.

The Importance of Apneic Events in Obstructive Sleep Apnea Associated with Acute Coronary Syndrome.

BACKGROUND: Obstructive sleep apnea (OSA) is a potential cardiovascular risk factor. However, there is currently no prominent screening strategy for its diagnosis in patients with acute coronary syndrome (ACS). The aim of this study was to establish the impact of apneic events in case of OSA associated with ACS. METHODS: Between January 1st and June 30th, fifty-three subjects with ACS (first acute myocardial infarction) were prospectively evaluated for OSA. Each patient was evaluated by polysomnography (PSG) two months after the ACS. RESULTS: Mean age of 59±9,6 years, 81,1% males, BMI at 28,5±4,2 kg/m2, neck circumference of 42,5±12,6 cm, and waist circumference os 102,5±16,5 cm. The majority of patients (73,6%) had moderate to severe OSA (apnea-hypopnea index (AHI) ≥ 15/h and arousal index ≥ 10/h). We defined the apneic coefficient (AC) as the ratio between apnea index (AI) and AHI. We chose as cut-off the median value of apnea coefficient in our population which was at 37%. The patients with a higher AC (AC ≥ 37% versus AC < 37%) had higher levels of Troponin-I (63,4±63,2 versus 29,7±36,1 ng/mL, p=0,016), higher levels of NT-proBNP (1879,8±2141,8 versus 480±621,3 pg/mL, p=0,001), higher SYNTAX score (15,8±11,5 versus 10,2±5,9, p=0,049), and lower left ventricle ejection fraction (LVEF 53,3±11,4 versus 59,4±6,4%, p=0,023) and were more likely to have a STEMI (21 patients (77,7%) vesus 14 patients (53,8%), p=0,031). CONCLUSION: An apneic coefficient (AI/AHI) ≥ 37% is correlated with more severe cardiac impairment, as well as higher hypoxemia and arousal index.

Evaluation of unattended automated titration to determine therapeutic continuous positive airway pressure in patients with obstructive sleep apnea.

BACKGROUND: Determination of the therapeutic pressure during continuous positive airway pressure (CPAP) therapy is usually performed by a technician during polysomnography. In recent years, several devices for automated adjustment of the therapeutic pressure by the means of computerized algorithms were developed. The aims of the present study were to compare two different devices for automated titration and to verify if unattended automated titration is a feasible strategy to determine the therapeutic CPAP. METHODS: We enrolled 16 consecutive patients with obstructive sleep apnea syndrome (OSAS) defined by an apnea-hypopnea index > 20/h. Automated titration was performed in the hospital using two CPAP devices (Autoset; Resmed; North Ryde, Australia; and Somnosmart; Weinmann; Hamburg, Germany) in random order for 2 consecutive nights, based on different signals for the detection of respiratory events. During titration, there was no direct supervision by a technician, and polysomnography was not recorded. We defined the therapeutic pressure as the 95th percentile of the airway pressure over time (P95). RESULTS: We observed significant differences of the P95 between the two devices, with an average of 7.0 +/- 2.5 cm H(2)O for the Somnosmart and 9.9 +/- 2.6 cm H(2)O for the Autoset (p = 0.005) [mean +/- SD]. There was a considerable lack of agreement between the two devices, with a bias of 3.0 cm H(2)O and limits of agreement ranging from + 9.3 to - 3.2 cm H(2)O. We found no significant correlation between the paired differences of P95 and either indexes of severity of OSAS or lung function variables. CONCLUSION: Automated titration based on the analyses of flow (Autoset) or forced oscillations (Somnosmart) predicted significant different therapeutic pressures for fixed CPAP therapy. Thus, unattended automated titration performed during 1 night of hospital stay with commercially available devices cannot be used to determine accurately the therapeutic CPAP in patients with OSAS.