COMET: a multicomponent home-based disease-management programme versus routine care in severe COPD.

The COPD Patient Management European Trial (COMET) investigated the efficacy and safety of a home-based COPD disease management intervention for severe COPD patients.The study was an international open-design clinical trial in COPD patients (forced expiratory volume in 1 s <50% of predicted value) randomised 1:1 to the disease management intervention or to the usual management practices at the study centre. The disease management intervention included a self-management programme, home telemonitoring, care coordination and medical management. The primary end-point was the number of unplanned all-cause hospitalisation days in the intention-to-treat (ITT) population. Secondary end-points included acute care hospitalisation days, BODE (body mass index, airflow obstruction, dyspnoea and exercise) index and exacerbations. Safety end-points included adverse events and deaths.For the 157 (disease management) and 162 (usual management) patients eligible for ITT analyses, all-cause hospitalisation days per year (mean±sd) were 17.4±35.4 and 22.6±41.8, respectively (mean difference -5.3, 95% CI -13.7 to -3.1; p=0.16). The disease management group had fewer per-protocol acute care hospitalisation days per year (p=0.047), a lower BODE index (p=0.01) and a lower mortality rate (1.9% versus 14.2%; p<0.001), with no difference in exacerbation frequency. Patient profiles and hospitalisation practices varied substantially across countries.The COMET disease management intervention did not significantly reduce unplanned all-cause hospitalisation days, but reduced acute care hospitalisation days and mortality in severe COPD patients.

Current evidence for the effectiveness of heated and humidified high flow nasal cannula supportive therapy in adult patients with respiratory failure.

High flow nasal cannula (HFNC) supportive therapy has emerged as a safe, useful therapy in patients with respiratory failure, improving oxygenation and comfort. Recently several clinical trials have analyzed the effectiveness of HFNC therapy in different clinical situations and have reported promising results. Here we review the current knowledge about HFNC therapy, from its mechanisms of action to its effects on outcomes in different clinical situations.

Effectiveness, Adherence and Safety of Home High Flow Nasal Cannula in Chronic Respiratory Disease and Respiratory Insufficiency: A Systematic Review.

INTRODUCTION: The effectiveness of home high flow nasal cannula (HFNC) for the treatment of chronic respiratory failure in patients with chronic respiratory diseases (CRDs) has not been summarized. We aimed to conduct a systematic review of the effectiveness, adherence, and safety of HFNC in the long-term treatment of patients with chronic respiratory diseases and respiratory failure. METHODS: A systematic review was conducted. PubMed, Web of science, and SCOPUS were search up to August 2023. Long-term HFNC studies (≥4 weeks) reporting dyspnea; exacerbations, hospitalizations; peripheral oxygen saturation (SpO2), comfort; patient experience, health-related quality of life or partial pressure of carbon dioxide (paCO2) were included. RESULTS: Thirteen articles (701 patients) based on 10 studies were selected: randomized control trials (n=3), randomized crossover trials (n=2), crossover (n=3) and retrospective (n=2) studies. COPD (n=6), bronchiectasis (n=2), COPD/bronchiectasis (n=1) and ILD (n=1) were the underlined CRDs. HFNC reduced exacerbations when compared to usual care/home respiratory therapies (n=6). Quality of life outcomes were also in favor of HFNC in patients with COPD and bronchiectasis (n=6). HFNC had significant effects on hospitalizations, paCO2, and lung function. Adherence ranged from 5.2 to 8.6h/day (n=5). Three studies reported no events, 3 non-serious events and 2 no differences compared with other home respiratory therapies. CONCLUSIONS: HFNC seems more effective than usual care or other home respiratory therapies in reducing exacerbations and improving quality of life in patients with COPD and bronchiectasis, while presenting good adherence and being safe. Its apparently superior effectiveness needs to be better studied in future real-world pragmatic trials.

A qualitative study of patient and carer experiences with home respiratory therapies: Long-term oxygen therapy and home mechanical ventilation.

Studies exploring the experience of patients receiving home respiratory therapies (HRT), such as long-term oxygen therapy (LTOT) and home mechanical ventilation (HMV), are still limited. This study focused on patients' and carers' experience with LTOT and HMV. An exploratory, cross-sectional qualitative study, using semi-structured focus groups, was carried out with 18 patients receiving HRT (median 71y, 78% male, 56% on both LTOT and HMV) and 6 carers (median age 67y, 67% female). Three focus groups were conducted in three regions of Portugal. Thematic analysis was performed by two independent researchers. Patients' and carers' experience was reflected in seven major topics, linked to specific time points and settings of the treatment: Initial symptoms/circumstances (n = 41), Prescription (n = 232), Implementation (n = 184), Carer involvement (n = 34), Quality of life impact (n = 301), Health care support/navigability (n = 173) and Suggestions (n = 14). Our findings demonstrate a general good perception of the HRT by patients and carers recognizing a significative quality of life impact improvement, while identifying specific points where improvements in healthcare are needed, particularly about navigability issues, articulation between the hospital, primary care and homecare teams, especially regardingprescriptionrenewal. This knowledge is crucial to promote a long-term HRT adherence and to optimize HRT delivery in line with patients' experience, needs, and values. Moreover, these key points can inform the development of a specific patient-reported experience measure (PREM) for patients on HRT, which is not currently available, and foster a more integrated respiratory care model.

Enhance Access to Pulmonary Rehabilitation with a Structured and Personalized Home-Based Program-reabilitAR: Protocol for Real-World Setting.

Home-based models represent one of the solutions to respond to the poor accessibility of pulmonary rehabilitation (PR) services in patients with chronic respiratory disease (CRD). The main goal of this protocol is to present the implementation of the first nationwide home-based PR program-reabilitAR-in Portugal and the strategies to assess its benefits in patients with CRD. The program consists of 2 phases: a 12-week intensive phase and a 40-week maintenance phase (total: 52 weeks, 1 year). The intervention in both phases is composed of presential home visits and phone-call follow ups, including exercise training and the self-management educational program Living Well with COPD. Dyspnea, impact of the disease, emotional status, and level of dyspnea during activities of daily living are used as patient-reported outcomes measures. A one-minute sit-to-stand test is used as a functional outcome, and the number of steps as a measure of physical activity. To ensure safety, fall risk and the cognitive function are assessed. Data are collected at baseline, at 12 weeks, at 26 weeks and at 52 weeks. This is the first nationwide protocol on enhancing access to PR, providing appropriate responses to CRD patients' needs through a structured and personalized home-based program in Portugal.

The Portuguese Model of Home Respiratory Care: Healthcare Professionals' Perspective.

Patients' and carers' views regarding the Portuguese model of home respiratory care were recently described, yet the complementary perspective of healthcare professionals (HCPs) is still to be investigated. Thus, this study explored HCPs experience in the management of patients needing home respiratory therapies (HRT), and their perspective about the Portuguese model. A phenomenological descriptive study, using focus groups, was carried out with 28 HCPs (median 42 y, 68% female) with distinct backgrounds (57% pulmonologists, 29% clinical physiologists, 7% physiotherapists, 7% nurses). Three focus groups were conducted in three regions of Portugal. Thematic analysis was performed by two independent researchers. HCPs have in general a positive view about the organization of the Portuguese model of home respiratory care, which was revealed in four major topics: Prescription (number of references, n = 171), Implementation and maintenance (n = 162), Carer involvement (n = 65) and Quality of healthcare (n = 247). Improvements needed were related to patients' late referral, HRT prescription (usability of the medical electronic prescription system and renewals burden), patients' education, access to hospital care team, lack of multidisciplinary work and articulation between hospital, primary and home care teams. This study describes the perspective of HCPs about the Portuguese model of home respiratory care and identifies specific points where improvements and reflections are needed. This knowledge may be useful to decision makers improve the current healthcare model.

Home Mechanical Ventilation Practices in Spain and Portugal.

Introduction: Home mechanical ventilation (HMV) practice has changed with publication of new evidence and introduction of new technologies, and varies between countries. This study investigated current HMV use and practices in Spain and Portugal. Methods: 94 healthcare professionals identified as regularly performing HMV-related activities were sent an e-mail link to an online questionnaire. The questionnaire included 40 items relating to responder demographics, non-invasive ventilation (NIV) care structure, ventilated patient profile, work habits, and potential future practice improvements. Results: 66 questionnaires (70%) were returned (Spain, 36; Portugal, 30). The majority of respondents were physicians (Spain, 95%; Portugal, 63%). Overall, 83% of hospitals had a dedicated NIV unit (Spain, 100%; Portugal, 63%). The most common indication for HMV was neuromuscular disorders in Spain and obstructive diseases in Portugal. Homecare providers (HCPs) and pulmonologists were usually responsible for managing HMV; HCPs were involved more often in Portugal. Choice of ventilator was most often based on usage hours/day; the most important device features were 'ease of use' (Spain) and 'adjustment range' (Portugal). HMV monitoring practices varied between countries. Telemonitoring was used more often in Portugal (20%; vs. Spain, 3%). Follow-up frequency and practices also differed markedly between Spain and Portugal. Respondents highlighted identification of new patient groups and patient phenotyping to optimize treatment and personalize therapy as future HMV strategies. Conclusions: Important differences in the management of HMV were observed between two similar European countries. Better understanding of clinical practices can facilitate targeted education and training to ensure optimal management of patients using HMV.

Introducción: El manejo de la ventilación mecánica domiciliaria (VMD) ha cambiado tras la publicación de información nueva y la introducción de nuevas tecnologías, y varía entre países. Este estudio investigó el uso y el manejo actuales de la VMD en España y Portugal. Métodos: Noventa y cuatro profesionales de la salud que realizaban actividades relacionadas con la VMD con regularidad recibieron un enlace mediante correo electrónico a un cuestionario en línea. El cuestionario incluyó 40 ítems relacionados con la demografía de los encuestados, la estructura de cuidados de la ventilación no invasiva (VNI), el perfil del paciente ventilado, los hábitos de trabajo y las posibles mejoras en el futuro manejo de la VMD. Resultados: Se respondieron 66 cuestionarios (70%) (España, 36; Portugal, 30). La mayoría de los encuestados eran médicos (España, 95%; Portugal, 63%). En total, el 83% de los hospitales tenían una unidad dedicada a la VNI (España, 100%; Portugal, 63%). La indicación más frecuente de VMD fueron los trastornos neuromusculares en España y las enfermedades obstructivas en Portugal. Los prestadores de servicios médicos domiciliarios (SMD) y los neumólogos generalmente fueron los responsables del manejo de la VMD. Los SMD participaron con mayor frecuencia en Portugal. La elección del ventilador se basó con mayor frecuencia en las horas de uso/día; las características más importantes del dispositivo fueron «facilidad de uso¼ (en España) y «rango de ajuste¼ (en Portugal). El manejo del seguimiento de la VMD varió entre países. La telemonitorización se utilizó con mayor frecuencia en Portugal (20%; frente a España, 3%). La frecuencia y la forma de seguimiento también difirieron notablemente entre España y Portugal. Los encuestados destacaron la identificación de nuevos grupos de pacientes y el fenotipado de los pacientes para optimizar el tratamiento y personalizar la terapia como estrategias futuras en la VMD. Conclusiones: Se observaron diferencias importantes en el manejo de la VMD entre dos países europeos similares. Una mejor comprensión de las prácticas clínicas puede facilitar la educación y la formación específicas para garantizar un manejo óptimo de los pacientes que utilizan VMD.

Effects on Humidification and Ventilatory Parameters of Three Single-limb Heated-wired Circuits for Non-invasive Ventilation: A Bench Study.

BACKGROUND: The objective of this study was to evaluate the effects of three single-limb heated wired circuits (SLHWC) for NIV, on ventilatory parameters and humidification performance in a simulation lung model. METHODS: Three SLHWC compatible with the MR-850 Heated Humidifier (HH) (Fisher & Paykel, Auckland, New Zealand) were tested: RT-319 (FP) (Fisher & Paykel, Auckland, New Zealand), Respironics 1045770 (RP) (DEAS, Castel Bolognese, Italy) and Intersurgical B/SYS 5809001 (IT) (Intersurgical, Wokingham, UK). A Bipap Vision ventilator (Philips Respironics, Murrysville, PA, USA) in pressure control ventilation (PCV) connected to a test lung was used for simulation. Each SHWC performance was evaluated in four ventilatory conditions: IPAP of 15cmH2O with FiO2 0.3 and 1, respectively; and, IPAP of 25cmH2O with FiO2 0.3 and 1, respectively. EPAP was set at 5cmH2O. Hygrometric and ventilatory measurements including: relative humidity (RH), temperature (T), Pplat, PIP, PEEP, peak inspiratory flow (PIF), and tidal volume (Vt) were measured. RESULTS: In each FiO2 group absolute humidity (AH) was similar with FP regardless of the IPAP level employed compared to IT and RP (P<.001). Except for RP at FiO2 0.3, AH increased significantly in IT and RP groups as IPAP increased (P<.001). PIP, Pplat, PEEP, PIF, and Vt values were significantly higher with FP and RP in each FiO2 group compared to IT (P<.001). CONCLUSIONS: Humidification performance varied significantly among the three circuits, being FP the only one able to maintain stable AH values during the study with no influence on ventilatory parameters.

A telephone-based survey of current trends, habits and beliefs in patients receiving portable oxygen therapy in Madrid, Spain.

Portable oxygen therapy is a major challenge for patients and clinicians. Additionally, the available evidence on this subject is poor considering that only a few studies have been published and the results have not been encouraging. We explored the current trends, habits and beliefs among patients receiving portable oxygen therapy in a geographical area of Madrid, Spain (4 051 862 inhabitants). A telephone-based survey was conducted among patients selected from a database who were undergoing portable oxygen therapy. The number of patients on home respiratory therapies on December 31, 2017 was 81 559 (prevalence 2013.30 per 100 000 inhabitants). A total of 19 492 patients were on home oxygen therapy (HOT) (prevalence 481.16 per 100 000 inhabitants). Of these, 4015 patients (20% of the total of patients on HOT) received ambulatory oxygen therapy. In the analysed period, 1942 patients were selected (57.31% male and 42.69% female). The mean±sd age was 73.89±11.67 years. Most of patients had portable oxygen concentrators (99.59%). The survey was completed by 1777 patients. Most of patients thought they had been prescribed HOT for respiratory failure. 55% of the participants surveyed reported having carried out a walking test with oxygen to know the amount of oxygen they needed. 71% of the participants reported leaving the home for between 1 and 3 h a day. Most of them were carrying portable devices in a wheeled cart (51.94%). Our study data obtained from a large sample of oxygen-dependent individuals provide valuable information regarding domiciliary and portable oxygen usage in Madrid.

New Perspectives in Oxygen Therapy Titration: Is Automatic Titration the Future? / Nuevas perspectivas en la titulación de la oxigenoterapia: ¿es la titulación automática el futuro?

Oxygen therapy, like all technology-based treatments, is continuously evolving. There are no doubts as to its effectiveness in the treatment of acute and respiratory failure in different clinical scenarios. However, the dosing guidelines for oxygen therapy are not as strict as for other treatments. The use of higher than necessary flows over excessively long periods, derived from the clinician's perception of it as a 'life-saving treatment with few side effects', has led to a rather liberal use of this intervention, despite evidence that overuse and suboptimal adjustment can be harmful. The titration of oxygen therapy, which is traditionally performed manually, has been shown to be beneficial. Recently, new devices have been developed that automatically adjust oxygen flow rates to the needs of each patient, in order to maintain stable oxygen saturation levels. These closed-loop oxygen supply systems can potentially reduce medical error, improve morbidity and mortality, and reduce care costs. Familiarizing the medical community with these technological advances will improve awareness of the risks of the inappropriate use of oxygen therapy. The aim of this paper is to provide an update of recent developments in oxygen therapy titration.

Virulence and resistance determinants of Klebsiella pneumoniae isolated from a Portuguese tertiary university hospital centre over a 31-year period.

INTRODUCTION: The rapid and complex evolution of bacterial resistance mechanisms in Klebsiella pneumoniae producing extended-spectrum ß-lactamases and carbapenemases in Klebsiella pneumoniae is one of the most significant threats to public health. However, questions and controversies regarding the interactions between resistance and virulence in multidrug-resistant K. pneumoniae isolates remain unclear. METHODS: A retrospective cohort study was performed with 100 K. pneumoniae isolates recovered from a tertiary care university hospital centre in Lisbon over a 31-year period. Resistance and virulence determinants were screened using molecular methods (PCR, M13-PCR and MLST). RESULTS: The predominant virulence profile (fimH, mrkDv1, khe) was shared by all isolates, indicative of an important role of type 1 and 3 fimbrial adhesins and haemolysin, regardless of the type of ß-lactamase produced. However, accumulation of virulence factors was identified in KPC-3-producers, with a higher frequency (p<0.05) of capsular serotype K2 and iucC aerobactin when compared with non-KPC-3 ß-lactamases or carbapenemases. Additionally, 9 different virulence profiles were found, indicating that the KPC-3 carbapenemase producers seem to adapt successfully to the host environment and maintain virulence via several pathways. CONCLUSION: This study describes an overlapping of multidrug-resistance and virulence determinants in ST-14K2 KPC-3 K. pneumoniae clinical isolates that may impose an additional challenge in the treatment of infections caused by this pathogen.

Spanish adaptation of the Amyotrophic Lateral Sclerosis Questionnaire ALSAQ-40 for ALS patients.

We studied the cross-cultural Spanish adaptation of the Amyotrophic Lateral Sclerosis Assessment Questionnaire (ALSAQ-40) to assess the subjective health status in amyotrophic lateral sclerosis (ALS) patients. The ALSAQ-40 questionnaire was adapted and applied to 53 randomly selected ALS patients from different regions in Spain. Reliability assessment and factorial analysis were performed in order to determine the dimensions of the scale. The validation was carried out by means of comparing the ALSAQ-40 with two instruments usually used in the assessment of ALS patients--the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) and the McGill's Quality of Life Questionnaire (MQOL), comparing the latter with the emotional dimension of ALSAQ-40. This Spanish adaptation closely resembles the ALSAQ-40 although the emotional dimension is more heterogeneous and there are cluster-gathering Feeding and Communication dimensions. ALSAQ-40 and ALSFRS questionnaires showed a high correlation, as did the emotional dimension of ALSAQ-40 with the Psychological Symptoms, Life Expectancy, Meaningful Existence and the whole score of the MQOL. In conclusion, this Spanish adaptation of ALSAQ-40 is in accordance with the statistical results from the original English version.

Do not do in COPD: consensus statement on overuse.

Background: To identify practices that do not add value, cause harm, or subject patients with chronic obstructive pulmonary disease (COPD) to a level of risk that outweighs possible benefits (overuse). Methods: A qualitative approach was applied. First, a multidisciplinary group of healthcare professionals used the Metaplan technique to draft and rank a list of overused procedures as well as self-care practices in patients with stable and exacerbated COPD. Second, in successive consensus-building rounds, description files were created for each "do not do" (DND) recommendation, consisting of a definition, description, quality of supporting evidence for the recommendation, and the indicator used to measure the degree of overuse. The consensus group comprised 6 pulmonologists, 2 general practitioners, 1 nurse, and 1 physiotherapist. Results: In total, 16 DND recommendations were made for patients with COPD: 6 for stable COPD, 6 for exacerbated COPD, and 4 concerning self-care. Conclusion: Overuse poses a risk for patients and jeopardizes care quality. These 16 DND recommendations for COPD will lower care risks and improve disease management, facilitate communication between physicians and patients, and bolster patient ability to provide self-care.

Efficacy and safety of high-flow nasal cannula oxygen therapy in patients with acute heart failure. / Efectividad y seguridad de la terapia de alto flujo con cánulas nasales en pacientes con insuficiencia cardiaca aguda.

OBJECTIVES: To evaluate the efficacy and safety of high-flow nasal cannula (HFNC) oxygen therapy in patients in acute respiratory failure due to acute heart failure (AHF) refractory to conventional oxygen therapy or noninvasive ventilation. METHODS: Prospective observational study of patients with AHF and respiratory failure attended in an emergency department whose condition worsened after they were admitted to a short-stay unit, leading to use of HFNCs. Efficacy was assessed using a modified Borg dyspnea scale and oxygenation variables on discharge from the emergency department. Data were recorded after 24 hours on conventional oxygen therapy and after 60 and 120 minutes and 24 hours of HFNC therapy. Safety outcomes were the degree of patient comfort and the frequency of adverse events. RESULTS: Prospective observational study of patients with AHF and respiratory failure attended in an emergency department whose condition worsened after they were admitted to a short-stay unit, leading to use of HFNCs. Efficacy was assessed using a modified Borg dyspnea scale and oxygenation variables on discharge from the emergency department. Data were recorded after 24 hours on conventional oxygen therapy and after 60 and 120 minutes and 24 hours of HFNC therapy. Safety outcomes were the degree of patient comfort and the frequency of adverse events. CONCLUSION: HFNC oxygen therapy offers a treatment alternative for patients with acute respiratory failure due to AHF.

OBJETIVOS: Valorar la eficacia y seguridad de la terapia de alto flujo con cánulas nasales (TAFCN) en pacientes con insuficiencia respiratoria aguda (IRA) secundaria a insuficiencia cardiaca aguda (ICA) y refractaria al tratamiento con oxigenoterapia convencional o ventilación no invasiva. METODOS: Estudio observacional prospectivo de pacientes con ICA e IRA atendidos en un servicio de urgencias, con ingreso posterior en una unidad de corta estancia, que, tras 24 horas presentaron empeoramiento y a los que se administró TAFCN. Para evaluar la eficacia se utilizó la escala de disnea modificada de Borg y la oxigenación al alta de urgencias, a las 24 h de tratamiento con oxigenación convencional y a los 60, 120 minutos y 24 h de iniciada la TAFCN. Para evaluar la seguridad se midió grado de confort y eventos adversos producidos. RESULTADOS: Se recogieron 44 pacientes con edad media de 84 (7) años, 75 % mujeres. El uso de la TAFCN supuso una mejoría significativa en los parámetros clínicos y gasométricos (basal, 60 min, 120 min y 24 h), en la escala de disnea y confort, oximetría y cociente de oxigenación y una disminución de la frecuencia respiratoria (p < 0,05). No hubo cambios significativos en la presión arterial de dióxido de carbono. El efecto secundario más frecuente fue el calor (20,4%). CONCLUSIONES: La TAFCN es una alternativa para el tratamiento de los pacientes con IRA secundaria a ICA.

The debate on continuous home oxygen therapy.

Two studies published in the early 80s, namely the Nocturnal Oxygen Therapy Trial (NOTT) and the Medical Research Council Trial (MRC), laid the foundations for modern home oxygen therapy. Since then, little progress has been made in terms of therapeutic indications, and several prescription-associated problems have come to light. Advances in technology have gone hand in hand with growing disregard for the recommendations in clinical guidelines on oxygen therapy. The introduction of liquid oxygen brought with it a number of technical problems, clinical problems related to selecting candidate patients for portable delivery devices, and economic problems associated with the rising cost of the therapy. Continuous home oxygen therapy has been further complicated by the recent introduction of portable oxygen concentrators and the development in quick succession of a range of delivery devices with different levels of efficiency and performance. Modern oxygen therapy demands that clinicians evaluate the level of mobility of their patients and the mobility permitted by available oxygen sources, correctly match patients with the most appropriate oxygen source and adjust the therapy accordingly. The future of continuous home oxygen therapy lies in developing the ideal delivery device, improving the regulations systems and information channels, raise patient awareness and drive research.

Oxygenation With a Single Portable Pulse-Dose Oxygen-Conserving Device and Combined Stationary and Portable Oxygen Delivery Devices in Subjects With COPD.

BACKGROUND: Portable oxygen devices simplify and facilitate patient therapy. This study was designed to compare S(pO2) and patient satisfaction with a portable oxygen concentrator or a combined system consisting of a fixed device with continuous-flow oxygen dispensation and a portable device with pulse dispensation for ambulation. METHODS: This crossover trial assessed 25 subjects with COPD (92% men, mean age of 72.2 ± 7.4 y, mean FEV1 of 34.14 ± 12.51% of predicted) at 4 hospitals in Madrid. All subjects had previously used the combined system, consisting of a fixed oxygenation system and a portable system for ambulation, with 16 (64%) using stationary and portable concentrators and 9 (36%) using a stationary reservoir and portable liquid oxygen bag. Oxygenation settings at rest and while walking were determined at baseline. Subjects were maintained on the previous combined system for 1 week and then switched to the portable oxygen concentrator for 1 week. Mean S(pO2) over 24 h was calculated using the software in the oximeter, and compliance was monitored (Visionox). RESULTS: Low S(pO2) (< 90%) was significantly more frequent during use of the portable concentrator alone than with the combined system (37.1% vs 18.4%, P < .05). The portable system alone was preferred by 43% of subjects, and the combined system was preferred by 36%, whereas 21% were not sure. CONCLUSIONS: Subjects preferred using a single portable oxygenation system both at home and during ambulation. Portable systems alone, however, did not supply the same levels of oxygenation as the combination of fixed and portable systems. Before the widespread adoption of portable systems as a single device, additional studies are needed to determine best-practice protocols for adjustment of daytime and nighttime oxygenation settings. (ClinicalTrials.gov registration NCT02079753).