Home Oxygen in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease and obstructive sleep apnea overlap: who to treat and how?

INTRODUCTION

The co-existence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA), or the overlap syndrome, is common and associated with a distinct pattern of nocturnal hypoxemia and worse clinical outcomes than either disease alone. Consequently, identifying who and how to treat these patients is essential.

AREAS COVERED

Treatment is recommended in all patients with OSA and symptoms or systemic hypertension, but determining symptoms attributable to OSA can be challenging in patients with COPD. Treatment should be considered in asymptomatic patients with moderate to severe OSA and COPD with pulmonary hypertension and comorbid cardiovascular and cerebrovascular disease, especially if marked hypoxic burden. CPAP is effective but in patients with the overlap syndrome and daytime hypercapnia, high-intensity noninvasive ventilation aiming to lower PaCO2 May have additional benefits. Additionally, in those with severe resting daytime hypoxemia, supplemental oxygen improves survival and should be added to positive airway pressure. The role of alternative non-positive airway pressure therapies in the overlap syndrome needs further study.

EXPERT OPINION

Both COPD and OSA are heterogeneous disorders with a wide range of disease severity and further research is needed to better characterize and prognosticate patients with the overlap syndrome to personalize treatment.

The benefits and drawbacks of home oxygen therapy for COPD: what's next?

INTRODUCTION

Home oxygen therapy is one of the few interventions that can improve survival in patients with chronic obstructive pulmonary disease (COPD) when administered appropriately, although it may cause side effects and be an unnecessary burden for some patients.

AREAS COVERED

This narrative review summarizes the current literature on the assessment of hypoxemia, different types of home oxygen therapy, potential beneficial and adverse effects, and emerging research on home oxygen therapy in COPD. A literature search was performed using MEDLINE and EMBASE up to January 2024, with additional articles being identified through clinical guidelines.

EXPERT OPINION

Hypoxemia is common in patients with more severe COPD. Long-term oxygen therapy is established to prolong survival in patients with chronic severe resting hypoxemia. Conversely, in the absence of chronic severe resting hypoxemia, home oxygen therapy has an unclear or conflicting evidence base, including for palliation of breathlessness, and is generally not recommended. However, beneficial effects in some patients cannot be precluded. Evidence is emerging on the optimal daily duration of oxygen use, the role of high-flow and auto-titrated oxygen therapy, improved informed decision-making, and telemonitoring. Further research is needed to validate novel oxygen delivery systems and monitoring tools and establish long-term effects of ambulatory oxygen therapy in COPD.

Smoking and home oxygen therapy: a review and consensus statement from a multidisciplinary Swedish taskforce

BACKGROUND

Home oxygen therapy (HOT) improves survival in patients with hypoxaemic chronic respiratory disease. Most patients evaluated for HOT are former or active smokers. Oxygen accelerates combustion and smoking may increase the risk of burn injuries and fire hazards; therefore, it is considered a contraindication for HOT in many countries. However, there is variability in the practices and policies regarding this matter. This multidisciplinary Swedish taskforce aimed to review the potential benefits and risks of smoking in relation to HOT, including medical, practical, legal and ethical considerations.

METHODS

The taskforce of the Swedish Respiratory Society comprises 15 members across respiratory medicine, nursing, medical law and ethics. HOT effectiveness and adverse risks related to smoking, as well as practical, legal and ethical considerations, were reviewed, resulting in five general questions and four PICO (population-intervention-comparator-outcome) questions. The strength of each recommendation was rated according to the GRADE (grading of recommendation assessment, development and evaluation) methodology.

RESULTS

General questions about the practical, legal and ethical aspects of HOT were discussed and summarised in the document. The PICO questions resulted in recommendations about assessment, management and follow-up of smoking when considering HOT, if HOT should be offered to people that meet the eligibility criteria but who continue to smoke, if a specific length of time of smoking cessation should be considered before assessing eligibility for HOT, and identification of areas for further research.

CONCLUSIONS

Multiple factors need to be considered in the benefit/risk evaluation of HOT in active smokers. A systematic approach is suggested to guide healthcare professionals in evaluating HOT in relation to smoking.

Respiratory Interventions, Hospital Utilization, and Clinical Outcomes of Persons with COPD and COVID-19

Purpose

Coronavirus disease 2019 (COVID-19) impacted outcomes of persons with chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD). This study investigated the differences in respiratory interventions, hospital utilization, smoking status, and 30-day readmission in those with COPD and COVID-19 based on hospital survival status.

Methods

A retrospective cross-sectional study was conducted from February 2020 to October 2020 and included persons with COPD and COVID-19 infection. We examined respiratory interventions, hospital utilization and outcomes, and 30-day hospital readmission. Chi-square test analysis was used to assess categorical variables, and t-test or Mann-Whitney was used to analyze continuous data based on normality.

Results

Ninety persons were included in the study, 78 (87%) were survivors. The most common comorbidity was hypertension 71 (78.9%) (p = 0.003). Twenty-two (24%) persons were intubated, from whom 12 (15%) survived (p < 0.001). There were 25 (32.1%) and 12 (100%), (p < 0.001) persons who required an ICU admission from the survivor and non-survivor groups, respectively. Among the survivor group, fifteen (19%) persons required 30-day hospital readmission.

Conclusion

Persons with COPD and COVID-19 had a lower mortality rate (13%) compared to other studies in the early pandemic phase. Non-survivors had increased ICU utilization, endotracheal intubation, and more frequent application of volume control mode. Discharging survivors to long-term acute care facilities may reduce 30-day hospital readmissions.

A Hybrid Effectiveness/Implementation Clinical Trial of Adherence to Long-Term Oxygen Therapy for Chronic Obstructive Pulmonary Disease

Rationale: Interventions to promote adherence to long-term oxygen therapy (LTOT) in chronic obstructive pulmonary disease (COPD) are needed. Objectives: To examine the real-world effectiveness of phone-based peer coaching on LTOT adherence and other outcomes in a pragmatic trial of patients with COPD. Methods: In a hybrid effectiveness/implementation pragmatic trial, patients were randomized to receive phone-based proactive coaching (educational materials, five phone-based peer coaching sessions over 60 d), reactive coaching (educational materials, peer coaching when requested), or usual care. Study staff members collected baseline and outcome data via phone at 30, 60, and 90 days after randomization. Adherence to LTOT over 60 days, the primary effectiveness outcome, was defined as mean LTOT use ⩾17.7 h/d. LTOT use was calculated using information about home oxygen equipment use in worksheets completed by study participants. Comparisons of adherence to LTOT between each coaching group and the usual care group using multivariable logistic regression models were prespecified as the primary analyses. Secondary effectiveness outcomes included Patient Reported Outcome Management Information System measures for physical, emotional, and social health. We assessed early implementation domains in the reach, adoption, and implementation framework. Results: In 444 participants, the proportions who were adherent to LTOT at 60 days were 74% in usual care, 84% in reactive coaching, and 70% in proactive coaching groups. Although reach, adoption by stakeholder partners, and intervention fidelity were acceptable, complete LTOT adherence data were available in only 73% of participants. Reactive coaching (adjusted odds ratio, 1.77; 97.5% confidence interval, 0.80-3.90) and proactive coaching (adjusted odds ratio, 0.70; 97.5% confidence interval, 0.34-1.46) did not improve adherence to LTOT compared with usual care. However, proactive coaching significantly reduced depressive symptoms and sleep disturbance compared with usual care and reduced depressive symptoms compared with reactive coaching. Unexpectedly, LTOT adherence was significantly lower in the proactive compared with the reactive coaching group. Conclusions: The results were inconclusive about whether a phone-based peer coaching strategy changed LTOT adherence compared with usual care. Further studies are needed to confirm the potential benefits of proactive peer coaching on secondary effectiveness outcomes and differences in LTOT adherence between proactive and reactive peer coaching. Clinical trial registered with ClinicalTrials.gov (NCT02098369).

Management of Chronic Obstructive Pulmonary Disease (COPD) Exacerbations in Hospitalized Patients From Admission to Discharge: A Comprehensive Review of Therapeutic Interventions

Chronic obstructive pulmonary disease (COPD) is a common and debilitating condition that often necessitates hospitalization for exacerbations. Since COPD exacerbations can cause significant morbidity and mortality, managing them is crucial for patient care. Effective management of COPD exacerbations is essential to prevent complications, as COPD exacerbations are associated with increased healthcare costs and decreased quality of life. This review aims to comprehensively discuss the management of COPD exacerbations, covering various pharmacologic and non-pharmacologic strategies. These include inhaled bronchodilators, systemic steroids, antibiotics, invasive and non-invasive ventilation, oxygen therapy, smoking cessation, immunization with pneumococcal vaccine, inhalers at discharge, pulmonary rehabilitation, long-term oxygen therapy (LTOT), ambulatory oxygen therapy, short-burst oxygen therapy, extracorporeal membrane oxygenation (ECMO), lung volume reduction surgery (LVRS), endobronchial procedures, and lung transplant. It is drawn upon various sources, including clinical studies, systemic reviews, and observational studies, to provide a comprehensive overview of current practices and identify areas for future research and innovation in managing COPD exacerbations. Addressing these areas of interest can improve patient outcomes and quality of life.

Effects of long-term oxygen therapy on the mental state of patients with chronic obstructive pulmonary disease: A systematic review

OBJECTIVES

This systematic review aimed to examine the effects of long-term oxygen therapy on the mental state of patients with chronic obstructive pulmonary disease.

METHODS

Web of Science, Medline, CINAHL, EMBASE, ProQuest, and Cochrane Library were selected to search for relevant studies. We followed the Cochrane Handbook for Systematic Reviews of Interventions, adopted the Cochrane risk-of-bias tool and Risk Of Bias In Non-randomized Studies of Interventions tool, and synthesized the outcomes narratively with Grading of Recommendations, Assessment, Development and Evaluations evidence profile.

RESULTS

Six studies were included. Moderate quality of evidence supported no effects of long-term oxygen therapy on the mental state in patients with severe resting hypoxemia and moderate resting hypoxemia (or exertional desaturation) at follow-up of 6 to 12 months; however, adverse effects on mental state among patients with moderate resting or exertional desaturation were reported at the follow-up of 36 to 48 months.

DISCUSSION

Nurses should focus on the mental state of patients treated with long-term oxygen therapy, especially those who use it for a prolonged time. Due to ethical constraints in this study, a quasi-experimental study with faithful consideration of internal validity can be commenced in the future.

Oxygen Therapy Part 2 - Indications and Toxicity

Oxygen Therapy Part 2: Indications and ToxicityWemple et al. continue their review of oxygen therapy, discussing the acute and chronic indications for oxygen and the delivery of supplemental oxygen (and its potential adverse effects and toxicity).

Adaptive exhaustion during prolonged intermittent hypoxia causes dysregulated skeletal muscle protein homeostasis

Nocturnal hypoxaemia, which is common in chronic obstructive pulmonary disease (COPD) patients, is associated with skeletal muscle loss or sarcopenia, which contributes to adverse clinical outcomes. In COPD, we have defined this as prolonged intermittent hypoxia (PIH) because the duration of hypoxia in skeletal muscle occurs through the duration of sleep followed by normoxia during the day, in contrast to recurrent brief hypoxic episodes during obstructive sleep apnoea (OSA). Adaptive cellular responses to PIH are not known. Responses to PIH induced by three cycles of 8 h hypoxia followed by 16 h normoxia were compared to those during chronic hypoxia (CH) or normoxia for 72 h in murine C2C12 and human inducible pluripotent stem cell-derived differentiated myotubes. RNA sequencing followed by downstream analyses were complemented by experimental validation of responses that included both unique and shared perturbations in ribosomal and mitochondrial function during PIH and CH. A sarcopenic phenotype characterized by decreased myotube diameter and protein synthesis, and increased phosphorylation of eIF2α (Ser51) by eIF2α kinase, and of GCN-2 (general controlled non-derepressed-2), occurred during both PIH and CH. Mitochondrial oxidative dysfunction, disrupted supercomplex assembly, lower activity of Complexes I, III, IV and V, and reduced intermediary metabolite concentrations occurred during PIH and CH. Decreased mitochondrial fission occurred during CH. Physiological relevance was established in skeletal muscle of mice with COPD that had increased phosphorylation of eIF2α, lower protein synthesis and mitochondrial oxidative dysfunction. Molecular and metabolic responses with PIH suggest an adaptive exhaustion with failure to restore homeostasis during normoxia. KEY POINTS: Sarcopenia or skeletal muscle loss is one of the most frequent complications that contributes to mortality and morbidity in patients with chronic obstructive pulmonary disease (COPD). Unlike chronic hypoxia, prolonged intermittent hypoxia is a frequent, underappreciated and clinically relevant model of hypoxia in patients with COPD. We developed a novel, in vitro myotube model of prolonged intermittent hypoxia with molecular and metabolic perturbations, mitochondrial oxidative dysfunction, and consequent sarcopenic phenotype. In vivo studies in skeletal muscle from a mouse model of COPD shared responses with our myotube model, establishing the pathophysiological relevance of our studies. These data lay the foundation for translational studies in human COPD to target prolonged, nocturnal hypoxaemia to prevent sarcopenia in these patients.

[The role of the physiotherapist in the assessment and management of dyspnea]

The role of the physiotherapist in the assessment and management of dyspnea. Dyspnea is the most common symptom in cardio-respiratory diseases. Recently improved comprehension of dyspnea mechanisms have underlined the need for three-faceted assessment. The three key aspects correspond to the "breathing, thinking, functioning" clinical model, which proposes a multidimensional - respiratory, emotional and functional - approach. Before initiating treatment, it is essential for several reasons to assess each specific case, determining the type of dyspnea affecting the patient, appraising the impact of shortness of breath, and estimating the effectiveness of the treatment applied. The physiotherapist has a major role to assume in the care of dyspneic patients, not only in assessment followed by treatment but also as a major collaborator in a multidisciplinary team, especially with regard to pulmonary rehabilitation. The aim of this review is to inventory the existing assessment tools and the possible physiotherapies for dyspnea, using a holistic approach designed to facilitate the choice of techniques and to improve quality of care by fully addressing the patient's needs.

Impact of respiratory viral infections on mortality and critical illness among hospitalized patients with chronic obstructive pulmonary disease

Background

Seasonal respiratory viral infections are associated with exacerbations and morbidity among patients with COPD. The real‐world clinical outcomes associated with seasonal viral infections are less well established among hospitalized patients.

Research Question

To estimate the association between seasonal respiratory viral infections, 30‐day mortality, and intensive care unit (ICU) admission among hospitalized COPD patients.

Study Design and Methods

We conducted an analysis of a national prospective multicenter cohort of COPD patients hospitalized with acute respiratory illness during winter seasons (2011–2015) in Canada. Nasopharyngeal swabs were performed on all patients at the onset of hospital admission for diagnosis of viral infection. Primary outcomes were 30‐day mortality and ICU admissions. Secondary outcomes included invasive/non‐invasive ventilation use.

Results

Among 3931 hospitalized patients with COPD, 28.5% (1122/3931) were diagnosed with seasonal respiratory viral infection. Viral infection was associated with increased admission to ICU (OR 1.5, 95% CI 1.2–1.9) and need for mechanical ventilation (OR 1.9, 95% CI 1.4–2.5), but was not associated with mortality (OR 1.1, 95% CI 0.8–1.4). Patients with respiratory syncytial virus (RSV) were equally likely to require ICU admission (OR 1.09, 95% CI 0.67–1.78), and more likely to need non‐invasive ventilation (OR 3.1; 95% CI 1.8–5.1) compared to patients with influenza.

Interpretation

Our results suggest COPD patients requiring hospitalization for respiratory symptoms should routinely receive viral testing at admission, especially for RSV and influenza, to inform prognosis, clinical management, and infection control practices during winter seasons. Patients with COPD will be an important target population for newly developed RSV therapeutics.

Clinical Trial Registration

ClinicalTrials.gov ID: NCT01517191.

[Computed tomographic imaging in chronic obstructive pulmonary disease : What pulmonologists and thoracic surgeons want to know]

Chronic obstructive pulmonary disease (COPD) begins with chronic inflammation of the bronchial system and leads to the development of emphysema in many patients. COPD patients are characterized by reduced performance, dyspnea in the context of an obstructive respiratory disorder and increased susceptibility to infections. COPD has a major impact on public health, as it is very common and many patients die from it. The most important preventable cause of COPD is tobacco smoke inhalation, which is why consistent smoking cessation is the most important component of any COPD treatment. There is no causal therapy, but in severely symptomatic patients with advanced emphysema, respiratory mechanics can be improved by lung volume reduction if all conservative treatment options have been exhausted. Diagnostic imaging is of great importance in the care of COPD patients. This article summarizes which indications warrant the performance of computed tomography (CT) and what we should pay special attention to during image analysis in order to provide optimal advice to our clinical partners.

Outcomes of Patients with Burns Associated with Home Oxygen Therapy: An Institutional Retrospective Review

Home oxygen therapy (HOT) burns carry high morbidity and mortality. Many patients are active smokers, which is the most frequent cause of oxygen ignition. We conducted a retrospective review at our institution to characterize demographics and outcomes in this patient population. An IRB-approved single-institution retrospective review was conducted for home oxygen therapy burn patients between July 2016 and January 2021. Demographic and clinical outcome data were compared between groups. We identified 100 patients with oxygen therapy burns. Mean age was 66.6 years with a male to female ratio of 1.3:1 and median burn surface area of 1%. In these patients, 97% were on oxygen for COPD and smoking caused 83% of burns. Thirteen were discharged from the emergency department, 35 observed for less than 24 hours, and 52 admitted. For admitted patients, 69.2% were admitted to the ICU, 37% required intubation, and 11.5% required debridement and grafting. Inhalational injury was found in 26.9% of patients, 3.9% underwent tracheostomy, and 17.3% experienced hospital complications. In-hospital mortality was 9.6% and 7.7% were discharged to hospice. 13.5% required readmission within 30 days. Admitted patients had significantly higher rates of admission to the ICU, intubation, and inhalational injury compared to those that were not admitted (p &lt; .01). Most HOT-related burns are caused by smoking and can result in significant morbidity and mortality. Efforts to educate and encourage smoking cessation with more judicious HOT allocation would assist in preventing these unnecessary highly morbid injuries.

Short-Term Oxygen Therapy Outcomes in COPD

Rationale

Short-term oxygen therapy (STOT) is often prescribed to allow patients with chronic obstructive pulmonary disease (COPD) to be discharged safely from hospital following an acute illness. This practice is widely accepted without being based on evidence.

Purpose

Our objective was to describe the characteristics and outcomes of patients with COPD who received STOT.

Patients and Methods

The study was a secondary analysis of the INOX trial, a 4-year randomised trial of nocturnal oxygen in COPD. The trial indicated that nocturnal oxygen has no significant effect on survival or progression to LTOT, allowing our merging of patients who received nocturnal oxygen and those who received placebo into a single cohort to study the predictors and outcomes of STOT regardless of the treatment received during the trial.

Results

Among the 243 participants in the trial, 60 required STOT on at least one occasion during follow-up. Patients requiring STOT had more severe dyspnoea and lung function impairment, and lower PaO₂ at baseline than those who did not. STOT was associated with subsequent LTOT requirement (hazard ratio [HR]: 4.59; 95% confidence interval [CI]: 2.98–7.07) and mortality (HR: 1.93; 95% CI: 1.15–3.24). The association between STOT and mortality was confounded by age, disease severity and comorbidities. Periods of STOT of more than one month and/or repeated prescriptions of STOT increased the probability of progression to LTOT (OR: 5.07; 95% CI: 1.48–18.8).

Conclusion

Following an acute respiratory illness in COPD, persistent hypoxaemia requiring STOT is a marker of disease progression towards the requirement for LTOT.

Patient-Centered Discussion on End-of-Life Care for Patients with Advanced COPD

Exacerbations of chronic obstructive pulmonary disease (COPD) may lead to a rapid decline in health and subsequent death, an unfortunate tyranny of having COPD-an irreversible health condition of 16 million individuals in the USA totaling 60 million in the world. While COPD is the third largest leading cause of death, causing 3.23 million deaths worldwide in 2019 (according to the WHO), most patients with COPD do not receive adequate treatment at the end stages of life. Although death is inevitable, the trajectory towards end-of-life is less predictable in severe COPD. Thus, clinician-patient discussion for end-of-life and palliative care could bring a meaningful life-prospective to patients with advanced COPD. Here, we summarized the current understanding and treatment of COPD. This review also highlights the importance of patient-centered discussion and summarizes current status of managing patients with advanced COPD.

Long-term oxygen therapy prescription in India: Evaluation of compliance, factors affecting compliance, indications, and survival

Introduction:

The international data shows that long-term oxygen therapy (LTOT) compliance is insufficient and variable. We conducted the first study from India on LTOT compliance, factors affecting compliance, indications, and survival through oxygen concentrator.

Materials and Methods:

Our organization from Delhi had given 378 oxygen concentrators over the last 5 years. We evaluated 120 patients randomly for participating in the study. Compliance was defined as the use of LTOT for at least 15 h/day.

Results:

Ninety-seven patients were included in the final analysis after exclusion criteria. The compliance to LTOT was seen in 45.36% (44/97). The commonest cause of noncompliance was lack of instructions (49.06%) followed by electricity issues, social stigma, and workplace constraints. A higher PaCO₂ was associated with significantly lower compliance (PaCO₂ 53.18 vs. 44.98 mmHg, P = 0.036). Interstitial lung disease was associated with significantly higher compliance. Oxygen prescription was titrated with arterial blood gas analysis in only 4.12%. The indications for LTOT were chronic obstructive pulmonary disease (49.48%), posttuberculous obstructive airway disease (20.6%), and interstitial lung disease (12.37%). We found a significant reduction in the mean number of exacerbations/year from 3.91 to 1.93 (P < 0.0001). 61.86% of the patients were surviving on LTOT with a median survival time of 12 months.

Conclusion:

The adherence to LTOT in Indian patients is suboptimal mainly due to lack of instruction and is associated with a higher PaCO₂. The practice of titration needs to be followed. The development of a national registry to monitor LTOT should be the long-term target.

Acetazolamide to Prevent Adverse Altitude Effects in COPD and Healthy Adults

BACKGROUND: We evaluated the efficacy of acetazolamide in preventing adverse altitude effects in patients with moderate to severe chronic obstructive pulmonary disease (COPD) and in healthy lowlanders 40 years of age or older. METHODS: Trial 1 was a randomized, double-blind, parallel-design trial in which 176 patients with COPD were treated with acetazolamide capsules (375 mg/day) or placebo, starting 24 hours before staying for 2 days at 3100 m. The mean (±SD) age of participants was 57±9 years, and 34% were women. At 760 m, COPD patients had oxygen saturation measured by pulse oximetry of 92% or greater, arterial partial pressure of carbon dioxide less than 45 mm Hg, and mean forced expiratory volume in 1 second of 63±11% of predicted. The primary outcome in trial 1 was the incidence of the composite end point of altitude-related adverse health effects (ARAHE) at 3100 m. Criteria for ARAHE included acute mountain sickness (AMS) and symptoms or findings relevant to well-being and safety, such as severe hypoxemia, requiring intervention. Trial 2 comprised 345 healthy lowlanders. Their mean age was 53±7 years, and 69% were women. The participants in trial 2 underwent the same protocol as did the patients with COPD in trial 1. The primary outcome in trial 2 was the incidence of AMS assessed at 3100 m by the Lake Louise questionnaire score (the scale of self-assessed symptoms ranges from 0 to 15 points, indicating absent to severe, with 3 or more points including headache, indicating AMS). RESULTS: In trial 1 of patients with COPD, 68 of 90 (76%) receiving placebo and 42 of 86 (49%) receiving acetazolamide experienced ARAHE (hazard ratio, 0.54; 95% confidence interval [CI], 0.37 to 0.79; P<0.001). The number needed to treat (NNT) to prevent one case of ARAHE was 4 (95% CI, 3 to 8). In trial 2 of healthy individuals, 54 of 170 (32%) receiving placebo and 38 of 175 (22%) receiving acetazolamide experienced AMS (hazard ratio, 0.48; 95% CI, 0.29 to 0.80; chi-square statistic P=0.035). The NNT to prevent one case of AMS was 10 (95% CI, 5 to 141). No serious adverse events occurred in these trials. CONCLUSIONS: Preventive treatment with acetazolamide reduced the incidence of adverse altitude effects requiring an intervention in patients with COPD and the incidence of AMS in healthy lowlanders 40 years of age or older during a high-altitude sojourn. (Funded by the Swiss National Science Foundation [Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung], Lunge Zürich, and the Swiss Lung Foundation; ClinicalTrials.gov numbers, NCT03156231 and NCT03561675.)

Social Participation and Associated Factors in Individuals with Chronic Obstructive Pulmonary Disease on Long-Term Oxygen Therapy

Long-term oxygen therapy (LTOT) reduces hypoxaemia and mitigate systemic alterations in chronic obstructive pulmonary disease (COPD), however, it is related to inactivity and social isolation. Social participation and its related factors remain underexplored in individuals on LTOT. This study investigated social participation in individuals with COPD on LTOT and its association with dyspnoea, exercise capacity, muscle strength, symptoms of anxiety and depression, and quality of life. The Assessment of Life Habits (LIFE-H) assessed social participation. The modified Medical Research Council dyspnoea scale, the 6-Minute Step test (6MST) and handgrip dynamometry were used for assessments. In addition, participants responded to the Hospital Anxiety and Depression Scale (HADS) and the Chronic Respiratory Questionnaire (CRQ). Correlation coefficients and multivariate linear regression analyses were applied. Fifty-seven participants with moderate to very severe COPD on LTOT were included (71 ± 8 years, FEV₁: 40 ± 17%predicted). Social participation was associated with dyspnoea (r_s=-0.46, p < 0.01), exercise capacity (r = 0.32, p = 0.03) and muscle strength (r = 0.25, p = 0.05). Better participation was also associated with fewer depression symptoms (r_s=-0.40, p < 0.01) and a better quality of life (r = 0.32, p = 0.01). Dyspnoea was an independent predictor of social participation (p < 0.01) on regression models. Restricted social participation is associated with increased dyspnoea, reduced muscle strength and exercise capacity. Better participation is associated with fewer depression symptoms and better quality of life in individuals with COPD on LTOT.

Alpha1-antitrypsin Disease, Treatment and Role for Lung Volume Reduction Surgery

Chronic obstructive pulmonary usually is subcategorized into 2 groups: chronic bronchitis and emphysema. The main cause of chronic bronchitis and emphysema is smoking; however, alpha1-antitrypsin also has been seen to cause emphysema in patients who are deficient. As symptoms and lung function decline, treatment modalities, such as lung volume reduction surgery, have been used in individuals with chronic obstructive pulmonary disease and upper lobe predominant emphysema. This article analyzes multiple published series where lung volume reduction surgery has been used in individuals with alpha1-antitrypsin deficiency and their overall outcomes.

Treatment of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial pneumonia of unknown cause, occurring in adults and limited to the lungs. In the past, treatment was aimed at minimizing inflammation and slowing the progression of inflammation to fibrosis. However, the underlying lesion in IPF may be more fibrotic than inflammatory, explaining why few patients respond to anti-inflammatory therapies and the prognosis remains poor.

In this review of literature, we will be focusing on main lines of treatment including current medications, supportive care, lung transplantation evaluation, and potential future strategies of treatment.

Incidence and Prognostic Significance of Hypoxemia in Fibrotic Interstitial Lung Disease: An International Cohort Study

BACKGROUND

Hypoxemia is a cardinal feature of fibrotic interstitial lung disease (ILD). The incidence, progression, and prognostic significance of hypoxemia in patients with fibrotic ILD currently is unknown.

RESEARCH QUESTION

What are the epidemiologic features of hypoxemia and its additive prognostic value in a current risk prediction model of fibrotic ILD?

METHODS

We identified 848 patients with fibrotic ILD (258 with idiopathic pulmonary fibrosis [IPF]) in five prospective ILD registries from Australia, Canada, and Switzerland. Cumulative incidence of exertional and resting hypoxemia from the time of diagnosis was estimated at 1-year intervals in patients with baseline 6-min walk tests, adjusted for competing risks of death and lung transplantation. Likelihood ratio tests were used to determine the prognostic significance of exertional and resting hypoxemia for 1-year mortality or transplantation when added to the ILD-GAP model. The cohort was divided into derivation and validation subsets to evaluate performance characteristics of the extended model (the ILD-GAP-O₂ model), which included oxygenation status as a predictor.

RESULTS

The 1-, 2-, and 5-year overall cumulative incidence was 6.1%, 17.3%, and 40.1%, respectively, for exertional hypoxemia and 2.4%, 5.6%, and 16.5%, respectively, for resting hypoxemia, which were significantly higher in patients with IPF compared with patients without IPF (P < .001 for both). Addition of exertional or resting hypoxemia to the ILD-GAP model improved 1-year mortality and transplantation prediction (P < .001 for both). The ILD-GAP-O₂ model showed improved discrimination (C-index, 0.80 vs 0.75) and model fit (Akaike information criteria, 400 vs 422) in the validation cohort, with comparable calibration.

INTERPRETATION

Patients with IPF have higher cumulative incidence of exertional and resting hypoxemia than patients without IPF. The extended ILD-GAP-O₂ model provides additional risk stratification for 1-year prognosis in fibrotic ILD.

Outcomes of patients with decreased arterial oxyhaemoglobin saturation on pulmonary arterial hypertension drugs

RATIONALE

Drugs approved for the treatment of pulmonary arterial hypertension (PAH) improve long-term outcomes. These drugs have pulmonary vasodilator properties which may potentially cause a decrease in arterial oxyhaemoglobin saturation (SaO₂) in some patients.

OBJECTIVES

The present retrospective study of the French PAH Registry aimed to describe clinical characteristics and outcomes of patients showing a ≥3% decrease in SaO₂ while treated with PAH drugs.

METHODS

We reviewed 719 PAH patients. The exclusion criteria were PAH associated with congenital heart disease and PAH with overt features of venous/capillaries involvement.

MAIN RESULTS

One hundred and seventy-three (24%) patients had a ≥3% decrease in SaO₂. At diagnosis, they were older, with a lower diffusion capacity for carbon monoxide and a shorter 6-minute walk distance, when compared to those who did not display a ≥3% decrease in SaO₂. The percentage of patients meeting the ESC/ERS low risk criteria at re-evaluation was significantly lower in those with a ≥3% decrease in SaO₂ and more patients started long-term oxygen therapy in this group (16% versus 5%, p<0.001). A≥3% decrease in SaO₂ was associated with a poorer survival (Hazard Ratio 1.81:95% confidence interval 1.43-2.34; p<0.0001). In a multivariate Cox analysis, a ≥3% decrease in SaO₂ was a prognostic factor independent of age at diagnosis and ESC/ERS risk stratification at follow-up.

CONCLUSIONS

When treated with PAH drugs, a large subset of patients experience a≥3% decrease in SaO₂, which is associated with worst long-term outcomes and reduced survival.

Reassessment of Home Oxygen Prescription after Hospitalization for Chronic Obstructive Pulmonary Disease. A Potential Target for Deimplementation

Rationale: Hypoxemia associated with acute exacerbations of chronic obstructive pulmonary disease (COPD) often resolves with time. Current guidelines recommend that patients recently discharged with supplemental home oxygen after hospitalization should not have renewal of the prescription without assessment for hypoxemia. Understanding patterns of home oxygen reassessment is an opportunity to improve quality and value in home oxygen prescribing and may provide future targets for deimplementation.Objectives: We sought to measure the frequency of home oxygen reassessment within 90 days of hospitalization for COPD and determine the potential population eligible for deimplementation.Methods: We performed a cohort study of patients ≥40 years hospitalized for COPD at five Veterans Affairs facilities who were prescribed home oxygen at discharge. Our primary outcome was the frequency of reassessment within 90 days by oxygen saturation (Sp_O2) measurement. Secondary outcomes included the proportion of patients potentially eligible for discontinuation (Sp_O2 > 88%) and patients in whom oxygen was discontinued. Our primary exposures were treatment with long-acting bronchodilators, prior history of COPD exacerbation, smoking status, and pulmonary hypertension. We used a mixed-effects Poisson model to measure the association between patient-level variables and our outcome, clustered by site. We also performed a positive deviant analysis using chart review to uncover system processes associated with high-quality oxygen prescribing.Results: A total of 287 of 659 (43.6%; range 24.8-78.5% by site) patients had complete reassessment within 90 days. None of our patient-level exposures were associated with oxygen reassessment. Nearly half of those with complete reassessment were eligible for discontinuation on the basis of Medicare guidelines (43.2%; n = 124/287). When using the newest evidence available by the Long-Term Oxygen Treatment Trial, most of the cohort did not have resting hypoxemia (84.3%; 393/466) and would be eligible for discontinuation. The highest-performing Veterans Affairs facility had four care processes to support oxygen reassessment and discontinuation, versus zero to one at all other sites.Conclusions: Fewer than half of patients prescribed home oxygen after a COPD exacerbation are reassessed within 90 days. New system processes supporting timely reassessment and discontinuation of unnecessary home oxygen therapy could improve the quality and value of care.

Effect of High-Flow Oxygen on Exercise Performance in COPD Patients. Randomized Trial

Background: High-flow oxygen therapy (HFOT) provides oxygen-enriched, humidified, and heated air at high flow rates via nasal cannula. It could be an alternative to low-flow oxygen therapy (LFOT) which is commonly used by patients with chronic obstructive pulmonary disease (COPD) during exercise training.

Research Question: We evaluated the hypothesis that HFOT improves exercise endurance in COPD patients compared to LFOT.

Methods: Patients with stable COPD, FEV₁ 40–80% predicted, resting pulse oximetry (SpO₂) ≥92%, performed two constant-load cycling exercise tests to exhaustion at 75% of maximal work rate on two different days, using LFOT (3 L/min) and HFOT (60 L/min, FiO₂ 0.45) in randomized order according to a crossover design. Primary outcome was exercise endurance time, further outcomes were SpO₂, breath rate and dyspnea.

Results: In 79 randomized patients, mean ± SD age 58 ± 9 y, FEV₁ 63 ± 9% predicted, GOLD grades 2-3, resting PaO₂ 9.4 ± 1.0 kPa, intention-to-treat analysis revealed an endurance time of 688 ± 463 s with LFOT and 773 ± 471 s with HFOT, mean difference 85 s (95% CI: 7 to 164, P = 0.034), relative increase of 13% (95% CI: 1 to 28). At isotime, patients had lower respiratory rate and higher SpO₂ with HFOT. At end-exercise, SpO₂ was higher by 2% (95% CI: 2 to 2), and Borg CR10 dyspnea scores were lower by 0.8 points (95% CI: 0.3 to 1.2) compared to LFOT.

Interpretation: In mildly hypoxemic patients with COPD, HFOT improved endurance time in association with higher arterial oxygen saturation, reduced respiratory rate and less dyspnea compared to LFOT. Therefore, HFOT is promising for enhancing exercise performance in COPD.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT03955770.

Oxygen Therapy in Sleep-Disordered Breathing

Sleep-disordered breathing (SDB) is highly prevalent in adults and leads to significant cardiovascular and neurologic sequelae. Intermittent hypoxia during sleep is a direct consequence of SDB. Administration of nocturnal supplemental oxygen (NSO) has been used as a therapeutic alternative to positive airway pressure (PAP) in SDB. NSO significantly improves oxygen saturation in OSA but is inferior to PAP in terms of reducing apnea severity and may prolong the duration of obstructive apneas. The effect of NSO on daytime sleepiness remains unclear, but NSO may improve physical function-related quality of life in OSA. Its effects on BP reduction remain inconclusive. The effects of NSO vs PAP in OSA with comorbid COPD (overlap syndrome) are unknown. NSO is effective in reducing central sleep apnea related to congestive heart failure; however, its impact on mortality and cardiovascular clinical outcomes are being investigated in an ongoing clinical trial. In conclusion, studies are inconclusive or limited regarding clinical outcomes with oxygen therapy compared with sham or PAP therapy in patients with OSA and overlap syndrome. Oxygen does mitigate central sleep apnea. This review examines the crucial knowledge gaps and suggests future research priorities to clarify the effects of optimal dose and duration of NSO, alone or in combination with PAP, on cardiovascular, sleep, and cognitive outcomes.

Portable Oxygen Therapy: Is the 6-Minute Walking Test Overestimating the Actual Oxygen Needs?

The appropriate titration for the personalized oxygen needs of patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia is a determining factor in the success of long-term oxygen therapy. There are no standardized procedures to assist in determining the patient’s needs during the physical activities of daily life. Despite that effort tests are a wide broad approach, further research concerning the development of protocols to titrate O₂ therapy is needed. The main objective of this study was to assess whether the level of oxygen titrated through the 6-minute walking test (6MWT) for patients with COPD and exertional hypoxemia is adequate to meet the patients’ demand during their activities of daily living. Physiological and subjective variables were estimated for a study population during two walking tests: a 6MWT and a 20-minute walking circuit (20MWC), designed ad-hoc to reproduce daily physical activities more truthfully. The results indicate that in a significant proportion of patients, the 6MWT might not accurately predict their oxygen needs at a domiciliary environment. Therefore, the titration of the portable O₂ therapy could not be optimal in these cases, with the detrimental impact on the patient’s health (hyperoxia episodes), the autonomy of the oxygen device, and the decrease of time out of the home.

Home Oxygen Therapy for Adults with Chronic Lung Disease. An Official American Thoracic Society Clinical Practice Guideline

Background: Evidence-based guidelines are needed for effective delivery of home oxygen therapy to appropriate patients with chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD).Methods: The multidisciplinary panel created six research questions using a modified Delphi approach. A systematic review of the literature was completed, and the Grading of Recommendations Assessment, Development and Evaluation approach was used to formulate clinical recommendations.Recommendations: The panel found varying quality and availability of evidence and made the following judgments: 1) strong recommendations for long-term oxygen use in patients with COPD (moderate-quality evidence) or ILD (low-quality evidence) with severe chronic resting hypoxemia, 2) a conditional recommendation against long-term oxygen use in patients with COPD with moderate chronic resting hypoxemia, 3) conditional recommendations for ambulatory oxygen use in patients with COPD (moderate-quality evidence) or ILD (low-quality evidence) with severe exertional hypoxemia, 4) a conditional recommendation for ambulatory liquid-oxygen use in patients who are mobile outside the home and require >3 L/min of continuous-flow oxygen during exertion (very-low-quality evidence), and 5) a recommendation that patients and their caregivers receive education on oxygen equipment and safety (best-practice statement).Conclusions: These guidelines provide the basis for evidence-based use of home oxygen therapy in adults with COPD or ILD but also highlight the need for additional research to guide clinical practice.

Oxygen for interstitial lung diseases

PURPOSE OF REVIEW

Supplemental oxygen therapy is prescribed for management of hypoxaemia in patients with interstitial lung disease (ILD). This review summarizes current evidence and implications of the use of supplemental oxygen therapy at home and during exercise training in ILD.

RECENT FINDINGS

Despite the significance of hypoxaemia in patients with ILD, there is a lack of high-quality evidence to guide the use of oxygen therapy in this population. Recent studies suggest that ambulatory oxygen may improve symptoms and health-related quality of life in patients with ILD. Long-term oxygen therapy for resting hypoxaemia in ILD is recommended by international guidelines. Supplemental oxygen during exercise may augment training effects, whereas therapeutic effects of nocturnal oxygen therapy are yet to be evaluated in patients with ILD. Nevertheless, it is important to consider the potential burden imposed by oxygen therapy on patients' daily activities of living.

SUMMARY

Ambulatory oxygen may be considered in ILD patients with exertional hypoxaemia, with long-term oxygen therapy being a standard care for resting hypoxaemia. Trials are currently underway to clarify therapeutic potentials of supplemental oxygen for exertional hypoxaemia and during exercise training in ILD patients, with additional research needed for the evaluation of nocturnal oxygen therapy.

Short Term Home Oxygen Therapy for COVID-19 patients: The COVID-HOT algorithm

Innovative solutions are required to effectively address the unprecedented surge of demand on our healthcare systems created by the COVID-19 pandemic. Home treatment and monitoring of patients who are asymptomatic or mildly symptomatic can be readily implemented to ameliorate the health system burden while maintaining safety and effectiveness of care. Such endeavor requires careful triage and coordination, telemedicine and technology support, workforce and education, as well as robust infrastructure. In the understandable paucity of evidence-based, protocolized approaches toward HOT for COVID-19 patients, our group has created the current document based on the cumulative experience of members of the Joint ACAIM-WACEM COVID-19 Clinical Management Taskforce. Utilizing available evidence-based resources and extensive front-line experience, the authors have suggested a pragmatic pathway for providing safe and effective home oxygen therapy in the community setting.

Automated Home Oxygen Delivery for Patients with COPD and Respiratory Failure: A New Approach

Long-term oxygen therapy (LTOT) has become standard care for the treatment of patients with chronic obstructive pulmonary disease (COPD) and other severe hypoxemic lung diseases. The use of new portable O₂ concentrators (POC) in LTOT is being expanded. However, the issue of oxygen titration is not always properly addressed, since POCs rely on proper use by patients. The robustness of algorithms and the limited reliability of current oximetry sensors are hindering the effectiveness of new approaches to closed-loop POCs based on the feedback of blood oxygen saturation. In this study, a novel intelligent portable oxygen concentrator (iPOC) is described. The presented iPOC is capable of adjusting the O₂ flow automatically by real-time classifying the intensity of a patient’s physical activity (PA). It was designed with a group of patients with COPD and stable chronic respiratory failure. The technical pilot test showed a weighted accuracy of 91.1% in updating the O₂ flow automatically according to medical prescriptions, and a general improvement in oxygenation compared to conventional POCs. In addition, the usability achieved was high, which indicated a significant degree of user satisfaction. This iPOC may have important benefits, including improved oxygenation, increased compliance with therapy recommendations, and the promotion of PA.

Physiologic Effects of Oxygen Supplementation During Exercise in Chronic Obstructive Pulmonary Disease

Supplemental long-term oxygen therapy (LTOT) is a well-established therapy that improves mortality in patients with chronic obstructive pulmonary disease (COPD) with resting hypoxemia. In the large number of patients with COPD who do not have severe resting hypoxemia but who desaturate with exercise, the clinical benefits that can be obtained by supplemental O₂ therapy during exercise is an area of interest and active research. A summary of current evidence for benefits of supplemental O₂ therapy and a review of physiologic mechanisms underlying published observations are reviewed in this article.

Optimizing Home Oxygen Therapy. An Official American Thoracic Society Workshop Report

More than 1.5 million adults in the United States use supplemental oxygen for a variety of respiratory disorders to improve their quality of life and prolong survival. This document describes recommendations from a multidisciplinary workshop convened at the ATS International Conference in 2017 with the goal of optimizing home oxygen therapy for adults. Ideal supplemental oxygen therapy is patient-specific, provided by a qualified clinician, includes an individualized prescription and therapeutic education program, and offers oxygen systems that are safe, promote mobility, and treat hypoxemia. Recently, patients and clinicians report a growing number of problems with home oxygen in the United States. Oxygen users experience significant functional, mechanical, and financial problems and a lack of education related to their oxygen equipment-problems that impact their quality of life. Health care providers report a lack of readily accessible resources needed to prescribe oxygen systems correctly and efficiently. Patients with certain lung diseases are affected more than others because of physically unmanageable or inadequate portable systems. Analysis is needed to quantify the unintended impact that the Centers for Medicare and Medicaid Services Competitive Bidding Program has had on patients receiving supplemental oxygen from durable medical equipment providers. Studies using effectiveness and implementation research designs are needed to develop and evaluate new models for patient education, identify effective ways for stakeholders to interface, determine the economic benefit of having respiratory therapists perform in-home education and follow-up testing, and collaborate with technology companies to improve portable oxygen devices. Generation of additional evidence of the benefit of supplemental oxygen across the spectrum of advanced lung diseases and the development of clinical practice guidelines should both be prioritized.

Clinician Strategies to Improve the Care of Patients Using Supplemental Oxygen

This article reviews four key clinician strategies to improve the care of adult patients receiving supplemental oxygen in the outpatient setting in the United States. The current barriers to adequate oxygen services are substantial and complex and include decreased reimbursement to durable medical equipment (DME) companies; a substantially lower number of available DME suppliers; difficult communication with DME suppliers; rigid patient testing, prescription, and documentation requirements; and unclear patient benefit and adherence. Recent data documenting frequent and varied problems reflect the significant impact of supplemental oxygen therapy on patients and caregivers. Areas where clinicians can improve patient oxygen experiences are highlighted in this review and include understanding Centers for Medicare and Medicaid Services oxygen prescription requirements, matching oxygen equipment to patient needs, providing essential patient education, and understanding mechanisms for patients and clinicians to report unresolved oxygen problems.

Patient registries for home oxygen research and evaluation

Randomized clinical trials are the preferred study design to address key research questions about the benefits or harms of interventions. However, randomized trials of oxygen therapy are difficult to conduct and have limitations. The purpose of this article is to offer our view on the potential use of patient registries in the field of home oxygen in COPD as an alternative to randomized trials by referring to the Swedish experience with a national registry for respiratory failure. Patient registries use observational study methods to collect uniform data (clinical and other) to evaluate specified outcomes for a population defined by a particular disease, condition, or exposure. As opposed to administrative databases, patient registries serve one or more predetermined scientific, clinical, or policy purposes. By systematically and prospectively compiling relevant data, patient registries may describe the natural history of a disease, determine effectiveness and cost-effectiveness, assess safety or harm, and measure quality of care. Registry-based randomized trials (ie, randomized trials within a clinical registry) combine the advantages of a prospective randomized trial with the strengths of a large-scale all-comers clinical registry. Challenges and issues in the design and implementation of patient registries include the representativeness of participants, data collection, quality assurance, ownership, and governance. Notwithstanding their limitations, patient registries represent valuable tools in the conduct of research in the area of home oxygen therapy.

Characteristics at the time of oxygen initiation associated with its adherence: Findings from the COPD Long-term Oxygen Treatment Trial

RATIONALE

Characteristics associated with adherence to long-term oxygen therapy (LTOT) in COPD remain unclear.

OBJECTIVES

To identify patient characteristics at the time of oxygen initiation associated with its adherence.

METHODS

We conducted a secondary analysis of data from 359 COPD participants assigned to oxygen in the Long-term Oxygen Treatment Trial. Participants were prescribed continuous (n = 214) or intermittent (n = 145) oxygen based on desaturation patterns at study entry. At the time of initial prescription, participants rated their perceived readiness, confidence, and importance to use oxygen on a 0-10 scale (0 = not at all, 10 = very much). During follow-up, they self-reported average hours per day of use (adherence). Adherence was averaged over short-term (0-30 days), medium-term (months 9-12), and long-term (month 13 to last follow-up) intervals. Multivariable logistic regression models explored characteristics associated with high adherence (≥16 h/day [continuous] or ≥8 h/day [intermittent]) during each time interval.

RESULTS

Participant readiness, confidence, and importance at the time of oxygen initiation were associated with high short- and medium-term adherence. For each unit increase in baseline readiness, the odds of high short-term adherence increased by 21% (odds ratio [OR] 1.21, 95% confidence interval [CI] 1.05-1.40) and 94% (OR 1.94, 95% CI 1.45-2.59) in the continuous and intermittent groups, respectively. In both groups, high adherence in the medium-term was associated with high adherence in the long-term (continuous, OR 12.49, 95% CI 4.90-31.79; intermittent, OR 38.08, 95% CI 6.96-208.20).

CONCLUSIONS

Readiness, confidence, and importance to use LTOT at initiation, and early high adherence, are significantly associated with long-term oxygen adherence.