Update in Noninvasive Home Mechanical Ventilation: A Narrative Review of Indications, Outcomes, and Monitoring.

Hypercapnic respiratory failure arises due to an imbalance in the load-capacity-drive relationship of the respiratory muscle pump, typically arising in patients with chronic obstructive pulmonary disease, obesity-related respiratory failure, and neuromuscular disease. Patients at risk of developing chronic respiratory failure and those with established disease should be referred to a specialist ventilation unit for evaluation and consideration of home noninvasive ventilation (NIV) initiation. Clinical trials demonstrate that, following careful patient selection, home NIV can improve a range of clinical, patient-reported, and physiological outcomes. This narrative review provides an overview of the pathophysiology of chronic respiratory failure, evidence-based applications of home NIV, and monitoring of patients established on home ventilation and describes technological advances in ventilation devices, interfaces, and monitoring to enhance comfort, promote long-term adherence, and optimise gas exchange.

Mask-related pressure injury prevention associated with non-invasive ventilation: A systematic review.

Noninvasive ventilation interfaces are one of the main factors contributing to pressure injuries caused by medical devices. Prevention is still the best course of action when discussing noninvasive ventilation-induced pressure injuries. A systematic review was designed to summarize and analyse all published literature on strategies to prevent pressure injuries caused by masks in patients undergoing noninvasive ventilation. The protocol of the systematic review followed the PRISMA guideline. An extensive search from the beginning to May 16, 2023, using current articles in databases such as Web of Science (WOS), Scopus, PubMed, and Cochrane Library was conducted. Medical Subject Headings (MESH) were used as follows: "Pressure Injury," "Noninvasive Ventilation," "Prevention," and "Pressure Sore." Any language-published studies that met the inclusion criteria were included in this review. A risk of bias assessment was conducted using the Joanna Briggs Institute tool, including evaluation methodologies for all studies. Database searches yielded 2546 articles, which were reduced to 23 that met our criteria after reviewing full texts. A narrative synthesis was conducted. As a result, type of interface (14 studies), dressings (4 studies), adjustment of mask leakage (1 study), humidity (1 study), positioning (1 study), and design of personalized masks (2 studies) seem to be a practical approach to prevent pressure injuries caused by masks in patients undergoing noninvasive ventilation. The results of our study show the effectiveness of preventive methods in reducing the incidence of pressure injuries caused by masks. Given the significant occurrence of pressure injury related to noninvasive ventilation and the crucial role of prevention and treatment, it is imperative to conduct more rigorous studies to ascertain the efficacy of each strategy.

Humidification during Invasive and Non-Invasive Ventilation: A Starting Tool Kit for Correct Setting.

The humidification process of medical gases plays a crucial role in both invasive and non-invasive ventilation, aiming to mitigate the complications arising from bronchial dryness. While passive humidification systems (HME) and active humidification systems are prevalent in routine clinical practice, there is a pressing need for further evaluation of their significance. Additionally, there is often an incomplete understanding of the operational mechanisms of these devices. The current review explores the historical evolution of gas conditioning in clinical practice, from early prototypes to contemporary active and passive humidification systems. It also discusses the physiological principles underlying humidity regulation and provides practical guidance for optimizing humidification parameters in both invasive and non-invasive ventilation modalities. The aim of this review is to elucidate the intricate interplay between temperature, humidity, and patient comfort, emphasizing the importance of individualized approaches to gas conditioning.

High-Flow Nasal Cannula Versus Noninvasive Ventilation as Initial Treatment in Acute Hypoxia: A Propensity Score-Matched Study.

IMPORTANCE: Patients presenting to the emergency department (ED) with hypoxemia often have mixed or uncertain causes of respiratory failure. The optimal treatment for such patients is unclear. Both high-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) are used. OBJECTIVES: We sought to compare the effectiveness of initial treatment with HFNC versus NIV for acute hypoxemic respiratory failure. DESIGN SETTING AND PARTICIPANTS: We conducted a retrospective cohort study of patients with acute hypoxemic respiratory failure treated with HFNC or NIV within 24 hours of arrival to the University of Michigan adult ED from January 2018 to December 2022. We matched patients 1:1 using a propensity score for odds of receiving NIV. MAIN OUTCOMES AND MEASURES: The primary outcome was major adverse pulmonary events (28-d mortality, ventilator-free days, noninvasive respiratory support hours) calculated using a win ratio. RESULTS: A total of 1154 patients were included. Seven hundred twenty-six (62.9%) received HFNC and 428 (37.1%) received NIV. We propensity score matched 668 of 1154 (57.9%) patients. Patients on NIV versus HFNC had lower 28-day mortality (16.5% vs. 23.4%, p = 0.033) and required noninvasive treatment for fewer hours (median 7.5 vs. 13.5, p < 0.001), but had no difference in ventilator-free days (median [interquartile range]: 28 [26, 28] vs. 28 [10.5, 28], p = 0.199). Win ratio for composite major adverse pulmonary events favored NIV (1.38; 95% CI, 1.15-1.65; p < 0.001). CONCLUSIONS AND RELEVANCE: In this observational study of patients with acute hypoxemic respiratory failure, initial treatment with NIV compared with HFNC was associated with lower mortality and fewer composite major pulmonary adverse events calculated using a win ratio. These findings underscore the need for randomized controlled trials to further understand the impact of noninvasive respiratory support strategies.

Customized Silicone Foam Dressing Under Noninvasive Ventilation and Skincare Bundle to Reduce Hospital-Acquired Pressure Injuries in Neonates.

In a sixty-eight-bed level-IV NICU, an increased incidence of hospital-acquired pressure injuries (HAPIs) from noninvasive ventilation (NIV) devices was identified. The aim of this quality improvement project was to decrease HAPIs from NIV by 10%. A literature review and the Plan-Do-Study-Act were implemented. The intervention included a customized silicone foam dressing under NIV, an NIV skincare bundle, and multidisciplinary support. Hospital-acquired pressure injury rates were tracked over 3 years postinterventions. The incidence of HAPIs declined by 20% from 0.2 per 1,000 patient days to 0.05 per 1,000 patient days. Relative risk was 4.6 times greater prior to intervention (p = .04). Continuous positive airway pressure (CPAP) failure was not noted and measured by the percentage of patients on ventilators pre- and postintervention. Customized silicone foam dressings under NIV, NIV skincare bundle, and multidisciplinary team support may decrease HAPIs in neonates without CPAP failure.

Mask interfaces and devices for home noninvasive ventilation in children.

Home noninvasive ventilation (NIV), including continuous (CPAP) and bilevel (BPAP) positive airway pressure, is increasingly used in children worldwide. In this narrative review, we present a comprehensive summary of the equipment available for home NIV in pediatrics, excluding neonates. NIV may be challenging in young children, as the majority of the equipment has been developed for adults. Regarding the interfaces, only a few masks have been specifically developed for young children in recent years, while older children may benefit from a large variety of interfaces. Even though much progress has been made, skin injuries are still present, and need to be managed rapidly. Several studies addressed the management of the side effects, but recent studies are lacking regarding orofacial anomalies. No recent study reported the available interfaces for young children and the strategies for an optimal mask fit. Regarding the devices, an adapted NIV device to pediatrics that allows an adequate patient's breathing detection should guarantee optimal ventilatory efficiency and monitoring of NIV. A close follow-up and regular monitoring should be mandatory to rule out the potential issues, optimize NIV therapy and ascertain the efficacy of NIV. However, studies are lacking to guide the choice of devices in young children and the optimal management of home NIV in pediatrics. We summarized the characteristics of the different interfaces available for young children and the limitations of NIV devices. We finally addressed potential areas for future research on long-term home NIV in children.

Residual upper airway obstruction during nocturnal noninvasive ventilation despite high positive expiratory pressure. Impact of oronasal mask to nasal mask switch.

BACKGROUND: Nasal mask (NM) and oronasal masks (OM) can be used to provide noninvasive ventilation (NIV). Recent studies suggested that OM is the most used interface and that there is no difference in efficacy or in tolerance between OM and NM for chronic use. However, studies focusing on video laryngoscopy underlined the impact of OM in residual upper airway obstruction (UAO) under NIV. We sought to assess the real-life practice of switching from OM to NM when UAO events persist despite high EPAP levels. METHODS: In an open-label single center prospective cohort study, data from files and full night polysomnography on NM and OM were collected for patients wearing OM and presenting an UAO index ≥15/h despite an EPAP level ≥ 10 cmH20. RESULTS: Forty-four patients were included in the study. In 31 patients (74 %), switching to a NM reduced UAOi to ≥10/h. Interestingly, 92 % of these patients still had NM at 3 to 12 months of follow-up. Switching to a NM was also associated with a trend in paCO2 reduction and significant improvements in Epworth, sleep quality and NIV compliance. Successful interface switching was significantly associated with female gender, and a trend was observed in non-smokers. CONCLUSION: As for CPAP, switching to a NM improved NIV efficacy in a selected group of patients presenting residual UAO events despite high EPAP levels. Additionally, this switch has an impact on compliance and subjective sleepiness. Thus, in patients with persisting UAO on OM, switching to a NM could be a first-line intervention before considering further investigation such as polygraphy or video laryngoscopy. We also derive an algorithm for mask allocation and adaptation in acute and chronic NIV use.

A Novel Mask with Selective Ports for Inflow and Outflow Reduces CO2 Rebreathing during Non-Invasive Ventilation: A Physiological Study in Healthy Volunteers.

BACKGROUND: CO2 rebreathing is one of the risks associated with noninvasive ventilation (NIV), possibly contributing to failure. In a bench study, we showed that a novel mask design, with separate limbs for inflow and outflow gases, significantly reduced CO2 rebreathing in different ventilation settings. OBJECTIVES: The study aimed to test whether a new mask design could 1) reduce CO2 rebreathing in healthy volunteers during NIV (phase 1) and 2) reduce minute ventilation (phase 2). MATERIALS AND METHODS: Healthy volunteers were randomly assigned to NIV using two masks in a crossover design: a traditional single-limb mask for inflow and outflow gases and a mask with two separated limbs. In phase 1, six ventilation settings were tested for each mask: CPAP (PEEP 5 cmH2O) and pressure support ventilation (PSV, PS Level 5 cmH2O) using a mechanical ventilator with a bias flow of 8 or 20 L/min; free-flow CPAP (PEEP 5 cmH2O) with 60 or 90 L/min of gas flow. A nasal cannula was inserted in one nostril of the volunteers and connected to a CO2 gas analyzer to measure CO2 during the respiratory cycle. In phase 2, volunteers underwent a prolonged time of ventilation in CPAP 90 L/min and PSV with 20 L/min of bias flow. During free-flow CPAP, electrical impedance tomography was used to record the change in impedance during tidal breathing and then estimate tidal volume. RESULTS: Ten healthy adults were enrolled in phase 1, and 8 volunteers in phase 2. CO2 during inspiration was significantly lower in each setting with the two-limb versus the one-limb mask (p < 0.001). The maximum CO2 reduction was observed in the continuous-flow CPAP settings. EtCO2 was lower with the two-limb mask compared to the one-limb mask (p < 0.001). However, no difference in minute ventilation was observed between the two masks. CONCLUSION: The new mask design with two ports for inhaled and exhaled gases reduced the amount of CO2 rebreathing in all tested ventilation settings. The CO2 rebreathing reduction did not decrease minute ventilation in healthy volunteers.

Conceptual model of low-cost improvised bubble continuous positive airway pressure device for adults and its potential use in the COVID-19 pandemic.

Low-cost improvised continuous positive airway pressure (CPAP) device is safe and efficacious in neonatal respiratory distress. There is a great necessity for similar device in adults, and this has been especially made apparent by the recent Coronavirus Disease 2019 (COVID-19) pandemic, which is unmasking the deficiencies of healthcare system in several low-resource countries. We propose a simplified and inexpensive model of improvised CPAP in adults using locally available resources including aquarium air pumps and a novel pressure release mechanism. Although the safety and efficacy of improvised CPAP in adults are not established, the conceptual model we propose has the potential to serve as a lifesaving technology in many low-resource settings during this ongoing pandemic and thus calls for expedited research.

Baricitinibe para tratamento de pacientes adultos com Covid-19 hospitalizados que necessitam de oxigênio por máscara ou cateter nasal, ou que necessitam de alto fluxo de oxigênio ou ventilação não invasiva / Baricitinib for the treatment of hospitalized adult patients with Covid-19 who require oxygen by mask or nasal catheter, or who require high flow oxygen or non-invasive ventilation

INTRODUÇÃO: O baricitinbe, um imunomodulador que atua sobre a atividade da IL-6 (citocina pró-inflamatória), pode representar uma estratégia para o tratamento de pacientes com COVID-19 que tiveram comprometimento pulmonar devido a resposta hiperinflamátoria desencadeada pela tempestade de citocinas característica na infecção causada pelo vírus SARS-COV2. TECNOLOGIA: Baricitinibe (Olumiant®). EVIDÊNCIAS CLÍNICAS: Para seleção das evidências clínicas foi conduzida uma revisão sistemática da literatura em busca de ensaios clínicos randomizados (ECR), estudos observacionais (mundo real) e revisões sistemáticas que avaliassem os efeitos do baricitinibe como monoterapia ou associado aos cuidados usuais - definidos aqui como 'terapia padrão' (corticoesteróides sistêmicos, anticoagulantes, antimicrobianos/antivirais) no tratamento de pacientes adultos com COVID-19, hospitalizados e que necessitam de suplementação de oxigênio (máscara ou cateter nasal, alto fluxo de oxigênio ou ventilação não invasiva). As buscas eletrônicas foram realizadas nas bases de dados: the Cochrane Library, MEDLINE via Pubmed, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), EMBASE e Centre for Reviews and Dissemination (CRD). O risco de viés dos estudos primários incluídos foi avaliado pelas ferramentas Risk of Bias versão 2 da Cochrane (para ECR) ou ROBINS-I (para estudos observacionais), e a qualidade metodológica das revisões sistemáticas foi avaliada pela ferramenta AMSTAR-2. A qualidade da evidência foi avaliada pelo sistema GRADE. Seis artigos foram incluídos na presente revisão, sendo dois deles referentes a um ensaio clínico randomizado (ECR), um estudo observacional e três revisões sistemáticas com meta-análise (RSMA), sendo uma

Ampliação de uso da ventilação não invasiva no tratamento das manifestações pulmonares crônicas e graves de pacientes com Fibrose Cística / Expanding the use of non-invasive ventilation in the treatment of chronic and severe pulmonary manifestations of patients with Cystic Fibrosis

INTRODUÇÃO: A fibrose cística (FC) é uma doença genética autossômica recessiva rara que pode estar presente em todos os grupos étnicos, mas predomina na população caucasiana. Ocorre por mutação em um gene que codifica a proteína reguladora de condução transmembrana da FC (CFTR), cuja deficiência ou ausência ocasiona a desidratação e o aumento da viscosidade das secreções mucosas, favorecendo obstrução das vias aéreas, ductos intrapancreáticos, ductos seminíferos e vias biliares. É uma doença multissistêmica, que acomete principalmente os sistemas respiratório e digestivo, sendo o comprometimento pulmonar o responsável pela maior morbimortalidade dos portadores. O acúmulo de muco espesso nas vias respiratórias inferiores e a presença de reação inflamatória local são as características chave da sua fisiopatogenia. O pulmão torna-se cronicamente infectado por bactérias e os ciclos repetidos de inflamação e remodelação na evolução da doença levam à doença obstrutiva crônica e irreversível. O Protocolo Clínico e Diretrizes Terapêuticas (PCDT) de FC atual do Ministério da Saúde (MS), de 2017, preconiza tratamento tradicional com a remoção das secreções das vias aéreas com alfadornase, visando melhorar a função pulmonar, diminuir a frequência das exacerbações respiratórias, melhorar a qualidade de vida e a hiperinsuflação pulmonar; Recomenda também o uso de tobramicina inalatória, para a manutenção ou melhora da função pulmonar, redução da contagem de colônias de Pseudomonas aeruginosa no escarro e redução das internações. TECNOLOGIA: Ventilação não invasiva (VNI). PERGUNTA: VNI é uma opção terapêutica adjuvante segura e eficaz para o tratamento da fibrose cística associada a insuficiência respiratória avançada? EVIDÊNCIAS CIENTÍFICAS: Com bas

The Intermittent Abdominal Pressure Ventilator as an Alternative Modality of Noninvasive Ventilatory Support: A Narrative Review.

ABSTRACT: Noninvasive ventilation has become the initial treatment for symptomatic ventilatory pump failure but, when used at ventilatory support settings, can be an alternative to tracheostomy mechanical ventilation. The intermittent abdominal pressure ventilator, a corset with an internal air sack inflated by a ventilator, allows to increase tidal volumes through the raising of the diaphragm and its consequent passive descent. It has been used for daytime support for more than 70 yrs, but its knowledge among clinicians is scarce. A narrative review was performed by searching PubMed, Medline, and the Cochrane Database of Systematic Reviews using the terms "IAPV" or "pneumobelt." One hundred forty patients were cited using the intermittent abdominal pressure ventilator from 1946 until it went off the market in the 1970s, although many continued to use it. There was only one publication on its use from 2003 to 2017, but three publications from 2017 through 2021. It has been used for full diurnal ventilatory support by some patients for more than 50 yrs and has even been used throughout the labor of a mother with no ventilator-free breathing ability. The intermittent abdominal pressure ventilator is a ventilatory support alternative for patients with ventilatory pump failure. It can be effective and well tolerated and maintain quality of life without facial interfaces. More widespread application is warranted.

The use of head helmets to deliver noninvasive ventilatory support: a comprehensive review of technical aspects and clinical findings.

A helmet, comprising a transparent hood and a soft collar, surrounding the patient's head can be used to deliver noninvasive ventilatory support, both as continuous positive airway pressure and noninvasive positive pressure ventilation (NPPV), the latter providing active support for inspiration. In this review, we summarize the technical aspects relevant to this device, particularly how to prevent CO2 rebreathing and improve patient-ventilator synchrony during NPPV. Clinical studies describe the application of helmets in cardiogenic pulmonary oedema, pneumonia, COVID-19, postextubation and immune suppression. A section is dedicated to paediatric use. In summary, helmet therapy can be used safely and effectively to provide NIV during hypoxemic respiratory failure, improving oxygenation and possibly leading to better patient-centred outcomes than other interfaces.

Oxygenation strategies during flexible bronchoscopy: a review of the literature.

During flexible fiberoptic bronchoscopy (FOB) the arterial partial pressure of oxygen can drop, increasing the risk for respiratory failure. To avoid desaturation episodes during the procedure several oxygenation strategies have been proposed, including conventional oxygen therapy (COT), high flow nasal cannula (HFNC), continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV). By a review of the current literature, we merely describe the clinical practice of oxygen therapies during FOB. We also conducted a pooled data analysis with respect to oxygenation outcomes, comparing HFNC with COT and NIV, separately. COT showed its benefits in patients undergoing FOB for broncho-alveolar lavage (BAL) or brushing for cytology, in those with peripheral arterial oxyhemoglobin saturation < 93% prior to the procedure or affected by obstructive disorder. HFNC is preferable over COT in patients with mild to moderate acute respiratory failure (ARF) undergoing FOB, by improving oxygen saturation and decreasing the episodes of desaturation. On the opposite, CPAP and NIV guarantee improved oxygenation outcomes as compared to HFNC, and they should be preferred in patients with more severe hypoxemic ARF during FOB.

Association Between Adaptive Servo-Ventilation Therapy and Renal Function.

Cardio-renal syndrome is a challenging clinical entity to manage, and is often associated with increased morbidity and mortality. We hypothesized that adaptive servo-ventilation (ASV), non-invasive positive pressure ventilation that ameliorates systemic/pulmonary congestion, may improve renal function in patients with symptomatic heart failure complicated by the cardio-renal syndrome. Patients with symptomatic congestive heart failure who underwent ASV therapy for over 1 month were included in this retrospective study. The trajectory of the estimated glomerular filtration ratio (eGFR) between the pre-1 month period and the post-one-month period (on ASV) were compared. A total of 81 patients (median 65 years old, 65 men) were included. eGFR decreased during the pre-1 month period from 52.7 (41.7, 64.6) down to 49.9 (37.3, 63.5) mL/minute/1.73 m2 (P < 0.001) whereas we observed an increase following one-month of ASV therapy up to 53.4 (38.6, 68.6) mL/minute/1.73 m2 (P = 0.022). A reduction in furosemide equivalent dose following the initiation of ASV therapy was independently associated with increases in eGFR with an adjusted odds ratio of 13.72 (95% confidence interval 3.40-55.3, P < 0.001). In conclusion, short-term ASV therapy was associated with the preservation of renal function, particularly when the dose of loop diuretics was concomitantly reduced.

Optimal NIV Medicare Access Promotion: Patients With COPD: A Technical Expert Panel Report From the American College of Chest Physicians, the American Association for Respiratory Care, the American Academy of Sleep Medicine, and the American Thoracic Society.

This document summarizes the work of the COPD Technical Expert Panel working group. For patients with COPD, the most pressing current coverage barriers identified were onerous diagnostic requirements focused on oxygenation (rather than ventilation) and difficulty obtaining bilevel devices with backup rate capabilities. Because of these difficulties, many patients with COPD were instead sometimes prescribed home mechanical ventilators. Critical evidence supports changes to current policies, including randomized controlled trial evidence suggesting a mortality benefit from bilevel positive airway pressure with backup rate and updated clinical practice guidelines from the American Thoracic Society as well as the European Respiratory Society. To achieve optimal access to noninvasive ventilation for patients with COPD, we make the following key recommendations: (1) removal of the need for overnight oximetry testing; (2) the ability to initiate therapy using bilevel devices with backup rate capability; and (3) increased duration of time to meet adherence criteria (ie, a second 90-day trial period) in those patients actively engaged in their care. Clear guidelines based on medical necessity are also included for patients who require initiation of or switch to a home mechanical ventilator. Adoption of these proposed recommendations would result in the right device, for the right type of patient with COPD, at the right time. Finally, we emphasize the need for adequate clinical support during initiation and maintenance of home noninvasive ventilation in such patients.

Executive Summary: Optimal NIV Medicare Access Promotion: A Technical Expert Panel Report From the American College of Chest Physicians, the American Association for Respiratory Care, the American Academy of Sleep Medicine, and the American Thoracic Society.

The current national coverage determinations (NCDs) for noninvasive ventilation for patients with thoracic restrictive disorders, COPD, and hypoventilation syndromes were formulated in 1998. New original research, updated formal practice guidelines, and current consensus expert opinion have accrued that are in conflict with the existing NCDs. Some inconsistencies in the NCDs have been noted, and the diagnostic and therapeutic technology has also advanced in the last quarter century. Thus, these and related NCDs relevant to bilevel positive airway pressure for the treatment of OSA and central sleep apnea need to be updated to ensure the optimal health of patients with these disorders. To that end, the American College of Chest Physicians organized a multisociety (American Thoracic Society, American Academy of Sleep Medicine, and American Association for Respiratory Care) effort to engage experts in the field to: (1) identify current barriers to optimal care; (2) highlight compelling scientific evidence that would justify changes from current policies incorporating best evidence and practice; and (3) propose suggestions that would form the basis for a revised NCD in each of these 5 areas (thoracic restrictive disorders, COPD, hypoventilation syndromes, OSA, and central sleep apnea). The expert panel met during a 2-day virtual summit in October 2020 and subsequently crafted written documents designed to achieve provision of "the right device to the right patient at the right time." These documents have been endorsed by the participating societies following peer review and publication in CHEST and will be used to inform efforts to revise the current NCDs.

Optimal NIV Medicare Access Promotion: Patients With Central Sleep Apnea: A Technical Expert Panel Report From the American College of Chest Physicians, the American Association for Respiratory Care, the American Academy of Sleep Medicine, and the American Thoracic Society.

This document summarizes suggestions of the central sleep apnea (CSA) Technical Expert Panel working group. This paper shares our vision for bringing the right device to the right patient at the right time. For patients with CSA, current coverage criteria do not align with guideline treatment recommendations. For example, CPAP and oxygen therapy are recommended but not covered for CSA. On the other hand, bilevel positive airway pressure (BPAP) without a backup rate may be a covered therapy for OSA, but it may worsen CSA. Narrow coverage criteria that require near elimination of obstructive breathing events on CPAP or BPAP in the spontaneous mode, even if at poorly tolerated pressure levels, may preclude therapy with BPAP with backup rate or adaptive servoventilation, even when those devices provide demonstrably better therapy. CSA is a dynamic disorder that may require different treatments over time, sometimes switching from one device to another; an example is switching from BPAP with backup rate to an adaptive servoventilation with automatic end-expiratory pressure adjustments, which may not be covered. To address these challenges, we suggest several changes to the coverage determinations, including: (1) a single simplified initial and continuing coverage definition of CSA that aligns with OSA; (2) removal of hypoventilation terminology from coverage criteria for CSA; (3) all effective therapies for CSA should be covered, including oxygen and all PAP devices with or without backup rates or servo-mechanisms; and (4) patients shown to have a suboptimal response to one PAP device should be allowed to add oxygen or change to another PAP device with different capabilities if shown to be effective with testing.