Hypoxic burden and sleep hypoventilation in obese patients.

INTRODUCTION: Novel biomarkers of hypoxic load have emerged, as sleep apnea-specific hypoxic burden which provides more precise assessment of intermittent hypoxemia severity. Our main objective was to assess the potential benefit of hypoxic burden to identify obesity-related sleep hypoventilation. We hypothesized that hypoxic burden may help diagnose obesity-related sleep hypoventilation better than usual sleep respiratory measures (i.e., apnea-hypopnea index (AHI), mean SpO2, time with SpO2 < 90 %). METHODS: This retrospective study was conducted from June 2022 to October 2023 at the University Hospital of Rouen, France. All consecutive obese patients (BMI ≥30 kg/m2), adults, with no other respiratory or neurological diseases who underwent a polysomnography or polygraphy with concomitant capnography were included. Sleep hypoventilation was defined according to American Academy of Sleep Medicine criteria based on transcutaneous CO2 monitoring (PtcCO2). Diagnostic performance of sleep-related respiratory measures i.e., sleep apnea-specific hypoxic burden, apnea-hypopnea index (AHI), mean SpO2, time with SpO2 < 90 % was evaluated using Receiver Operating Characteristic (ROC) curves. Correlations between sleep-related respiratory measures were assessed by a Spearman correlation matrix. RESULTS: Among 107 obese patients with analyzed capnography, 37 (35 %) had sleep hypoventilation. Patients were 53 ± 14 years old, mean BMI = 38 ± 6 kg/m2, mean AHI = 26.5 ± 25/h, mean hypoxic burden = 67 ± 109 %min/h, mean SpO2 = 91.5 ± 3 %, mean time with SpO2<90 % = 19.4 ± 28 %, mean PtcCO2 = 6.2 ± 0.7 kPa. A low positive correlation was found between hypoxic burden and mean PtcCO2 (r = 0.4, p < 0.001). Multivariate logistic regression model explaining sleep hypoventilation was insufficient with area under ROC curve of hypoxic burden estimated at 0.74 (95 % CI 0.65 to 0.84). CONCLUSION: Hypoxic burden has low correlation with transcutaneous CO2 pressure and a low ability to diagnose obesity-related sleep hypoventilation.

[High-flow nasal oxygen therapy and hypercapnic acute respiratory failure]. / Oxygénothérapie nasale à haut débit et insuffisance respiratoire aiguë hypercapnique.

Humidified high-flow nasal oxygen therapy (HFNO) has, in recent years, come to assume a key role in the management of hypoxemic acute respiratory failure (ARF). While non-invasive ventilation (NIV) currently represents the first-line ventilatory strategy in patients exhibiting hypercapnic ARF, the operating principles and physiological effects of HFNO could be interesting and useful in the initial management of hypercapnic ARF and/or after extubation, particularly in acute exacerbations of chronic obstructive pulmonary disease. Under these conditions, HFNO could be used either alone continuously or in combination with NIV during breaks in spontaneous breathing, depending on the severity and etiology of the underlying hypercapnic ARF.

[Physiotherapy and COVID-19. From intensive care unit to home care-An overview of international guidelines]. / Kinésithérapie et COVID-19 : de la réanimation à la réhabilitation à domicile. Synthèse des recommandations internationales.

INTRODUCTION: The new coronavirus disease 2019 (COVID-19) is responsible for a global pandemic and many deaths. This context requires an adaptation of health systems as well as the role of each healthcare professional, including physiotherapists. STATE OF THE ART: In order to optimize the management of people with COVID-19, many savant societies published guidelines about physiotherapy interventions within the crisis but none offered a global overview from the intensive care unit to home care. Therefore, the aim of this review is to offer an overview of recommended physiotherapy interventions in order to facilitate the management of these patients, whatever the stage of the disease. PERSPECTIVES: Owing to the emergent character of the COVID-19, actual guidelines will have to be adjusted according to the evolution of the pandemic and the resources of the hospital and liberal sectors, in particular for the long-term follow-up of these patients. Current and future research will aim to assess the effectiveness of physiotherapy interventions for people with COVID-19. CONCLUSION: The emergence of COVID-19 required a very rapid adaptation of the health system. The role of physiotherapists is justified at every stage of patients care in order to limit the functional consequences of the disease.

[The influence of anxiety and depression on COPD exacerbations]. / Influence de l'anxiété et de la dépression sur les exacerbations au cours de la BPCO.

INTRODUCTION: Exacerbations are common during the course of chronic obstructive pulmonary disease (COPD) and contribute to its morbidity and mortality. COPD is also associated with high prevalence of anxiety and depression. OBJECTIVES: A systematic literature review of data on the association between anxiety and/or depression and COPD exacerbations. DOCUMENTARY SOURCES: Medline search, for the 1980-2017 period, with the following keywords: "chronic obstructive pulmonary disease" or "COPD" and "exacerbation" and "anxiety" or "depression"; limits: "title/abstract"; the selected languages were English or French. RESULTS: Among 152 articles, 77 abstracts have been preselected for a dual reading and 30 studies have been finally selected. The prevalence of anxiety and depression ranged from 6.7 to 58% and 5.5 to 51.5%, respectively. Among the 30 studies included in this review, 19 (63.3%) revealed positive associations between anxiety and/or depression and increased risk for exacerbations, although 11 (36.7%) failed to support such an association. The association between anxiety and/or depression and an increased risk of COPD exacerbations was more frequently observed in studies using an event-based definition (85.7%) than in those using a symptom-based definition (14.3%). The main limitation of this review is the high heterogeneity of the studies included. Another limitation is the low rate of women included in this review (32.6%). CONCLUSION: Anxiety and/or depression are associated with a greater risk for exacerbations to occur in COPD. However, a high heterogeneity across the published studies makes it difficult to draw any firm conclusions on the amplitude of this increased risk.

[Cohort of patients initiated to home ventilation. Observational and prospective study]. / Cohorte de patients nouvellement traités par ventilation non invasive à domicile. Étude observationnelle, prospective et multicentrique.

Cohort of patients initiated to home ventilation. Observational and prospective study. The effectiveness of home noninvasive ventilation (NIV) for chronic respiratory failure (CRF) is well established. However, few data are available about home NIV prescription and utilization according to the different etiologies of respiratory failure. The ANTADIR Federation, in partnership with the Ventilatory Support Group of the French Speaking Pulmonary Society, has set up a national, observational and multicenter cohort study. The main goal of this study is to analyze the clinical data justifying home NIV prescription in patients with chronic respiratory insufficiency. The secondary objectives will be to assess: the evolution of comorbidities or their occurrence, hospitalizations, NIV compliance, dropout and survival. The population includes patients with chronic respiratory failure newly initiated onto NIV, both in a stable state and following an acute exacerbation who qualify for long-term NIV. Data collected include: diagnosis and comorbidities, age, sex, BMI, biomarkers (hematocrit, arterial blood gases, total CO2) and functional data (FEV1, VC, TLC), nocturnal results (SaO2, PtcCO2), type of ventilator used, ventilator parameters and mask type. Follow-up data will be collected at 4 months, 1 year and 2 years and will include: hospitalizations, changes in prescription, adherence, dropouts and deaths. This work will make it possible to obtain new scientific information on long-term NIV use in France.

[Noninvasive ventilation. The 2015 guidelines from the Groupe Assistance Ventilatoire (GAV) of the Société de Pneumologie de Langue Française (SPLF)]. / Ventilation non invasive. Les conseils 2015 du Groupe assistance ventilatoire (GAV) de la Société de pneumologie de langue française (SPLF).

A task force issued from the Groupe Assistance Ventilatoire (GAV) of the Société de Pneumologie de Langue Française (SPLF) was committed to develop a series of expert advice concerning various practical topics related to long-term non invasive ventilation by applying the Choosing Wisely® methodology. Three topics were selected: monitoring of noninvasive ventilation, the interpretation of data obtained from built-in devices coupled to home ventilators and the role of hybrid modes (target volume with variable pressure support. For each topic, the experts have developed practical tips based on a comprehensive analysis of recent insights and evidence from the literature and from clinical experience.

[Cardiopulmonary interactions in the course of mechanical ventilation]. / Interactions cœur­poumons au cours de la ventilation mécanique.

INTRODUCTION: The haemodynamic consequences of ventilation are multiple and complex and may affect all the determinants of cardiac performance such as heart rate, preload, contractility and afterload. These consequences affect both right and left ventricle and are also related to the biventricular interdependence. STATE-OF-THE-ART: Ventilation modifies the lung volume and also the intrathoracic pressure. Variations in lung volume have consequences on the pulmonary vascular resistance, hypoxic pulmonary vasoconstriction and ventricular interdependence. Variations in intrathoracic pressure have a major impact and affect systemic venous return, right ventricular preload, left ventricular preload, right ventricular afterload, left ventricular afterload and myocardial contracility. The haemodynamic consequences of positive pressure ventilation depend on the underlying chronic cardiopulmonary pathologies leading to the acute respiratory failure that was the indication for ventilation. CONCLUSION: In this review, we will focus on severe COPD exacerbation, acute left heart failure and weaning from ventilation.

Medium-term cost-effectiveness of an automated non-invasive ventilation outpatient set-up versus a standard fixed level non-invasive ventilation inpatient set-up in obese patients with chronic respiratory failure: a protocol description.

INTRODUCTION: Obesity is an escalating issue, with an accompanying increase in referrals of patients with obesity-related respiratory failure. Currently, these patients are electively admitted to hospital for initiation of non-invasive ventilation (NIV), but it is unknown whether outpatient initiation is as effective as inpatient set-up. We hypothesise that outpatient set-up using an autotitrating NIV device will be more cost-effective than a nurse-led inpatient titration and set-up. METHODS AND ANALYSIS: We will undertake a multinational, multicentre randomised controlled trial. Participants will be randomised to receive the usual inpatient set-up, which will include nurse-led initiation of NIV or outpatient set-up with an automated NIV device. They will be stratified according to the trial site, gender and previous use of NIV or continuous positive airway pressure. Assuming a 10% dropout rate, a total sample of 82 patients will be required. Cost-effectiveness will be evaluated using standard treatment costs and health service utilisation as well as health-related quality of life measures (severe respiratory insufficiency (SRI) and EuroQol-5 dimensions (EQ-5D)). A change in the SRI questionnaire will be based on the analysis of covariance adjusting for the baseline measurements between the two arms of patients. ETHICS AND DISSEMINATION: This study has been approved by the Westminster National Research Ethics Committee (11/LO/0414) and is the trial registered on the UKCRN portfolio. The trial is planned to start in January 2015 with publication of the trial results in 2017. TRIAL REGISTRATION NUMBER: ISRCTN 51420481.

[Noninvasive ventilation: efficacy of a new ventilatory mode in patients with obesity-hypoventilation syndrome]. / Ventilation non invasive : efficacité d'un nouveau mode ventilatoire chez les patients atteints du syndrome obésité-hypoventilation.

Noninvasive ventilation is recommended to correct the nocturnal hypoventilation and relieve the symptoms of patients with the obesity-hypoventilation syndrome (OHS). The benefits of fixed pressure ventilation (S/T technology) are recognized but limited on account of the variability of nocturnal ventilatory requirements. The new technique AVAPS-AE (automatic EPAP) allows adjustment of the pressure according to the volume currently targeted. Its efficacy has not yet been evaluated. Our objectives are to evaluate firstly, whether AVAPS-AE optimizes the benefits of S/T technology on sleep architecture and quality, secondly, whether these benefits are associated with an improvement in gas exchange, symptoms, exercise tolerance, level of physical activity and quality of life of patients with OHS. In this multicenter trial, 60 newly diagnosed patients with OHS will be randomized to the control (S/T) and trial (AVAPS-AE) groups. A standardized titration procedure will be followed for the calibration of the ventilators. Functional evaluations (polysomnography, blood gases, impedance measurements and walking tests), questionnaires (physical activity, quality of life, quality of sleep and daytime somnolence) visual scales (fatigue, headaches) and a recording of activity will be undertaken after two months of ventilation.

[Epidemiology and COPD screening in France. Workshop from the Société de Pneumologie de Langue Française (SPLF)]. / Épidémiologie et dépistage de la BPCO en France. Workshop de la Société de pneumologie de langue française (SPLF).

INTRODUCTION: A workshop has been organized in April 2013 by the Société de Pneumologie de Langue Française about COPD epidemiology and COPD screening in France and other European countries. This article deals with epidemiological data and their consequences on the French screening strategy. STATE-OF-THE-ART: According to the most recent data, spirometric prevalence of COPD in France is 7.5% in individuals over 45 years old. During 2000-2002, COPD was responsible for 1.4% of all causes of death in France and was mentioned to be an associated cause of death in 3% of all death certificates. The average medical costs for one COPD patient is estimated to be 4366 €/year, until 7502 €/year in very severe COPD patients. All clinical studies that have been performed in France show that COPD screening via mini-spirometry is feasible in general practice or in an ambulatory setting; however, a mass screening proved to be difficult to perform. A simple technique like the Piko-6(®) implies a concomitant formalized training. The non-reimbursement by the French Social Security is also a limiting factor, as the absence of medical and economical validation of this strategy. Therefore, COPD screening should be focused to individuals at risk and should include tobacco issues and cessation. CONCLUSION: COPD screening strategies have to be medically evaluated and experiments have to take the specificities of the French health organization into consideration. Any COPD screening strategy should be considered as an overall fight against the tobacco epidemics.