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).

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 in COPD

Long-term oxygen therapy (LTOT) is a mainstay treatment for patients with severe resting hypoxemia secondary to chronic respiratory conditions including COPD. The evidence for LTOT is based on two trials that are now several decades old but have been insufficiently revisited. Therefore, many questions remain about precisely which patients experience the most benefit from LTOT, as well as how to define that benefit. Most studies have examined LTOT's effect on longevity rather than its impact on quality of life. In addition, many challenges exist in training both clinicians and patients on best practices for LTOT and associated equipment. Reimbursement policies have reduced the kinds of equipment available to the LTOT patient community, presenting additional challenges. This paper will review the current evidence for LTOT in COPD, the challenges involved with providing optimal therapy, and potential avenues of modernizing this essential intervention.

Patient-Assessed Quality of Virtual Consultations as Follow-Up on Long-Term Oxygen Therapy for Patients With COPD

BACKGROUND

Long-term oxygen therapy (LTOT) can increase survival time and relieve symptom burden in patients with COPD and chronic hypoxemia. The Department of Respiratory Medicine at Odense University Hospital invites patients with LTOT and COPD to the out-patient clinic for treatment evaluation every 6 months to regulate or terminate treatment and support patients' treatment adherence. The out-patient clinic, however, experiences many absences or cancellations from patients. For that reason, patients were offered virtual consultation as an alternative to physical attendance. This study was initiated to uncover reasons for absences and the patients' experiences of virtual consultation to promote a more patient-centered clinical practice for patients with COPD and LTOT.

METHODS

A qualitative study encompassing semi-structured interviews with 20 subjects was conducted in the winter of 2021. The subjects had tried or been given the opportunity of virtual consultation. Data were analyzed inspired by Kvale and Brinkmann focusing on the subject's perspectives on virtual consultation.

RESULTS

The analysis resulted in 3 main themes: limitations and vulnerabilities, independence and quality of life, and personal strategies. Subjects expressed that everyday life with LTOT and COPD was characterized by limited resources in terms of energy, oxygen, and time. LTOT was perceived as a necessary means to maintain a sense of independence and quality of life. However, LTOT also meant additional limitations due to cumbersome equipment and feelings of isolation. Most subjects considered the virtual consultation to be oxygen-, energy-, and time-preserving, as it meant avoiding stressful transportation and handling of oxygen cylinders, COVID-19 exposure, waiting time, and not having to involve others for help.

CONCLUSIONS

The subjects' perspective showed that follow-up on LTOT as a virtual consultation was considered a valuable offer. The chosen method was found to be relevant in uncovering subjects' attitudes toward clinical practice procedures.

Evaluation of Over-the-Counter Portable Oxygen Concentrators Utilizing a Metabolic Simulator

BACKGROUND

Supplemental oxygen is designed to raise alveolar PO2 to facilitate diffusion into arterial blood. Oxygen is generally delivered by nasal cannula either by continuous or pulsatile flow. Battery-powered portable oxygen concentrators (POCs) facilitate ambulation in patients experiencing exertional hypoxemia. In the United States, the Food and Drug Administration (FDA) clears these devices to be sold by physician prescription. Recently, however, lower-cost devices described as POCs have been advertised by online retailers. These devices lack FDA clearance and are obtained over the counter (OTC) without prescription. This study determined whether a selected group of OTC POCs have oxygen delivery characteristics suitable for use by hypoxemic patients.

METHODS

A metabolic simulator, capable of simulating a range of metabolic rates and minute ventilations, determined effects of oxygen supplementation delivered by a variety of devices on alveolar PO2 . Devices tested included 3 OTC POCs, an FDA-cleared POC, and continuous-flow oxygen from a compressed oxygen cylinder. End-tidal PETO2 , a surrogate of alveolar PO2 , was determined at each of each device's flow settings at 3 metabolic rates.

RESULTS

Continuous-flow tank oxygen yielded a linear PETO2 increase as flow increased, with progressively lower slope of increase for higher metabolic rate. The prescription POC device yielded similar PETO2 elevations, though with somewhat smaller elevations in pulse-dose operation. One OTC POC was only technically portable (no on-board battery); it provided only modest PETO2 elevation that failed to increase as flow setting was incremented. A second OTC POC produced only minimal PETO2 elevation. A third OTC POC, a pulsed-dose device, produced meaningful PETO2 increases, though not as great as the prescription device.

CONCLUSIONS

Only one of 3 OTC POCs tested was potentially of use by patients requiring ambulatory oxygen. Physicians and respiratory therapists should inform patients requiring portable oxygen that OTC devices may not meet their oxygenation requirements.

Incidence, management, and outcome of lung cancer in patients with long-term oxygen therapy

BACKGROUND

Here, we aimed to assess the specific features of lung cancer in patients with long-term oxygen therapy (LTOT), and compare their outcomes with patients suffering from lung cancer without LTOT.

METHODS

This retrospective, case-controlled study included patients with LTOT and an incident diagnosis of lung cancer treated at Rouen University Hospital.

RESULTS

Out of 2201 patients with LTOT, 31 were diagnosed with lung cancer. Among 24 patients with proven lung cancer, the most frequent histological type was squamous cell carcinoma (n = 12/24, 50%). Active treatment of any type was given in 19/31 (61%) and 41/62 (66%) of patients in the LTOT and control groups, respectively (p = 0.83). In the LTOT group, median survival was 38 days with best supportive care and 462 days with active treatment (p = 0.003). However, when adjusting on performance status and disease stage, LTOT was not significantly associated with a worse outcome. Hazard ratio (HR): 1.56 (95% confidence interval [CI]: 0.87 to 2.81) (p = 0.137). Administration of any treatment was associated with a better prognostic: HR: 0.35 (95% CI: 0.19 to 0.66). Both groups had a similar treatment safety profile.

CONCLUSION

Incidence of lung cancer in patients with LTOT was comparable to the general population. The proportion of LTOT patients who received active treatment was similar to controls, and overall survival did not differ from controls in a multivariate analysis. Although reaching a histological diagnosis may be challenging in LTOT patients, the efficacy and safety of the management strategies of lung cancer seem preserved.

Cost-Effectiveness of an Extended Home Visit Program for Oxygen-Dependent COPD Patients

BACKGROUND

Long-term oxygen therapy in COPD is usually supervised through home-care respiratory programs. Such programs often involve an intensive education intervention at the initiation of long-term oxygen therapy, followed by an extended follow-up period that aims toward home oxygen adherence. The objective of this study was to estimate the cost-effectiveness ratio of such a maintenance program.

METHODS

A simulation model was developed that compared 2 strategies after the intensive education intervention: (1) enrollment and (2) no enrollment in a maintenance program. The study population consisted of a hypothetical cohort of 200 patients (100 patients per group; mean age, 74 years; 45% men; mean FEV₁ of 43% predicted value; and mean resting P_aO2 while breathing air, 50 mm Hg). Effectiveness assumptions of the program were derived from a current literature review. The primary outcome was the ratio of the incremental cost of the program per quality-adjusted life-years gained. Only direct costs were considered; a health-care system perspective was adopted. Costs are reported in 2020 Canadian dollars (Can $).

RESULTS

Over a 5-year period, an extended home-visit program may prevent 9 deaths and provide an additional 39 years of life and 24 quality-adjusted life-years. Compared with usual care (ie, no enrollment in the maintenance program), the incremental cost-effectiveness ratio was Can $17,197 per quality-adjusted life-years gained. Sensitivity analyses demonstrated the robustness of the model. Only a reduction in adherence of 25% per year would increase the incremental cost-effectiveness ratio per quality-adjusted life-years beyond the threshold of Can $50,000 that is usually considered as acceptable from a health-care system perspective.

CONCLUSIONS

An extended home-visit program to maintain or improve adherence to long-term oxygen therapy in patients with COPD would most likely be cost-effective.

Multidisciplinary Care and Prognosis in Patients With COPD and Interstitial Lung Disease Prescribed Long-Term Oxygen Therapy

BACKGROUND

Home oxygen therapy is prescribed for patients with advanced lung disease based on the criteria established in landmark trials in subjects with COPD. In clinical practice, its use has been extrapolated to other diseases, including interstitial lung disease (ILD). Patients with COPD and ILD experience a high symptom burden and require access to specialized multidisciplinary care. We aimed to evaluate the health-related outcomes and supportive care needs of patients with COPD and ILD receiving home oxygen therapy.

METHODS

This was a retrospective cohort study using the oxygen database of a quaternary metropolitan teaching hospital. Patients with a diagnosis of COPD or ILD who were prescribed home oxygen therapy between January 2012-December 2018 were identified. Demographic information, results of physiologic testing, comorbidities, hospitalizations, and mortality data were collected.

RESULTS

Three hundred and eighty-four subjects were included for analysis, of whom 56% were male. The median age was 75 y. The majority (59%) had a diagnosis of COPD. Long-term oxygen therapy (LTOT) was prescribed for 187 (48.7%), with no significant demographic differences between those with COPD or ILD. Another 187 were prescribed ambulatory oxygen alone, with 55 transitioning to LTOT during the study period. Most subjects (65.4%) were referred for pulmonary rehabilitation; however, palliative care referrals were generally low (22.9%). Referrals to other medical specialties and allied health were common (82%). Transplant-free survival after commencement of LTOT was poor, with 38% of subjects surviving at 5 y. The 5-y survival of subjects with ILD after commencing on LTOT was 10% compared to 52% for those with COPD. Multivariable Cox regression analyses showed that the only predictor of survival after commencing LTOT was the principal respiratory diagnosis.

CONCLUSIONS

This study found that subjects prescribed LTOT had poor transplant-free survival after initiation, which was significantly worse for those with ILD compared to those with COPD. Despite their poor overall survival, worse than many cancers, only a minority were referred for palliative care input. Referrals to pulmonary rehabilitation were also suboptimal. This patient population had complex care needs requiring multidisciplinary management. Appropriate and early referrals to palliative care and improved care coordination for this complex group of patients are key areas for improvement in clinical practice.

Lack of Medical Criteria for Long-Term Oxygen Therapy Usage According to International Guidance in Outpatients With Chronic Hypoxemia

Background

Benefits of long-term oxygen therapy (LTOT) have been observed in hypoxemic respiratory patients. Reports have shown the lack of observance among healthcare professionals of LTOT. Thus, this study aimed to determine the demographic characteristics and observance of the medical indication of LTOT according to the international guidelines.

Methodology

A cross-sectional study was conducted on patients who attended the Medical Unit in Aguascalientes, Mexico to re-evaluate the need for LTOT. Data are presented as mean ± standard deviation. Statistical analyses were performed using the chi-square test or unpaired t-tests. P-values of <0.05 were considered statistically significant.

Results

From 813 outpatients attended to re-evaluate whether they met the medical criteria to use LTOT, 93 outpatients were excluded, and the remaining 714 outpatients were enrolled. The mean age of the patients was 70.0 ± 15.1 years, with a female gender predominance (59.1 %). The mean PaO₂ level in room air was 7.9 ± 2.3 kPa. Hemoglobin and hematocrit levels were 14.9 ± 4.1 g/dL and 44.7 ± 8.4%, respectively. The mean levels of PaO₂ were higher in female patients (8.1 ± 2.5 kPa vs. 7.6 ± 1.9 kPa; p = 0.01). The most common diagnosis was chronic obstructive pulmonary disorder (60.5%). Moreover, the specialty that most indicated the use of LTOT was pulmonology (57.8%); however, 36.8% of patients who used LTOT did not have any criteria according to international guidelines.

Conclusions

Although a significant percentage of patients do not use LTOT correctly, the most important finding is that the medical indication of LTOT by physicians is not always correct, leading to an excessive prescription of oxygen.

Dietary Behaviour and Nutrition in Patients with COPD Treated with Long-Term Oxygen Therapy

BACKGROUND

It is the first study in Poland and one of the first in the world to assess the nutrition of patients with chronic obstructive pulmonary disease (COPD) treated with long-term oxygen therapy (LTOT).

METHODS

The study group consisted of 110 COPD patients treated with LTOT. Anthropometric measurements and spirometry were performed. The diet of patients was assessed using a 3-day nutrition diary.

RESULTS

When assessing the degree of airflow obstruction (FEV1% N) depending on the BMI in patients treated with LTOT, a statistically significant correlation was demonstrated between the BMI and the value of the FEV% N parameter (p = 0.0093). Patients with COPD with a BMI >30 had statistically significantly higher values of FEV1% N than patients with a BMI in the range of 20-24.9 (p = 0.0278). Intake of calcium, vitamins A, C, D, E and folates was lower than the recommended daily intake in more than 95% of COPD patients.

CONCLUSIONS

The diet of COPD patients treated with long-term oxygen therapy was improperly balanced, with deficiencies of important nutrients. Airflow obstruction in the respiratory tract was significantly smaller in obese patients, and greater in patients with diagnosed malnutrition.

Home-based Pulmonary Rehabilitation is Effective in Frail COPD Patients with Chronic Respiratory Failure

Daily life disability and vulnerability is often reported in patients with chronic obstructive pulmonary disease (COPD) and chronic respiratory failure. Although pulmonary rehabilitation is feasible in this population, its benefits on functional status and physical frailty is uncertain. This study aimed to evaluate the short- and medium-term effectiveness of a home-based pulmonary rehabilitation program in COPD patients with chronic respiratory failure. We also evaluate the impact of frailty status on the efficacy of the intervention. Forty-seven participants underwent an 8-week home-based program. Functional capacity, physical frailty (Fried criteria), exercise tolerance, health-related quality of life, general fatigue, and anxiety and depressive symptoms were assessed at baseline (M0), and at 8 weeks (M2) and 8 months (M8) following study inclusion. For the group as a whole, functional capacity, physical frailty, health-related quality of life and fatigue scores were all improved at M2 and M8 (p<0.05), while exercise tolerance and depressive symptoms were only improved at M8 (p<0.01). However, when the group was divided according to frailty status, only the frails patients had improved health related quality of life, general fatigue, and anxiety and depressive symptoms scores after PR (p<0.05). In COPD patients with chronic respiratory failure, home-based pulmonary rehabilitation may be effective for improving functional capacity, physical frailty and health related quality of life at short- and medium-term. Physical frailty was not a barrier for benefiting from the intervention, and almost 80% of the patients who were frail prior to the program improved their frailty status after pulmonary rehabilitation.

Using Telemedicine to Monitor the Patient with Chronic Respiratory Failure

Background: Advances in management have improved mortality of individuals with chronic respiratory failure (CRF), leading to an increase in need for long-term oxygen therapy and/or ventilatory support. These individuals require frequent visits and monitoring of their physiological parameters as well as of the functioning of their devices, such as ventilators or oxygen concentrators. Telemedicine is a clinical application of Information Communication Technology connecting patients to specialised care consultants. This narrative review aims to explore the current available telemonitoring options for individuals with CRF and reported or potential results. Methods: The research focused on EMBASE, CINALH, PubMed, and Scopus databases. Papers published between 2003 and 2021 in English were considered. Results: Different sensors, transmission devices and systems, and interventions are used with promising but not conclusive clinical results. However, legal problems are still unsolved, and economic advantages for health care systems, although potentially high, are still under debate. Conclusions: Telemonitoring systems for individuals with CRF are increasingly used; with promising results still to be clarified, legal, economical and organisational issues must be defined.

The efficacy of nintedanib in 158 patients with idiopathic pulmonary fibrosis in real-world settings: A multicenter retrospective study

Background:

The INPULSIS trials revealed that nintedanib reduced the decline in lung function in patients with idiopathic pulmonary fibrosis. We aimed to evaluate the efficacy and safety of nintedanib in Japanese idiopathic pulmonary fibrosis patients in real-world settings.

Method:

Medical records of idiopathic pulmonary fibrosis patients, who received treatment with nintedanib in five institutions between July 2015 and June 2017, were reviewed. Patients with % forced vital capacity ⩾50% and % predicted diffusing capacity of the lung carbon monoxide ⩾30% were classified as the moderate group and those with more impaired lung functions as the severe group.

Result:

Among 158 patients analyzed, 132 (84.6%) were classified as the moderate group and 26 (15.4%) as the severe group. In the moderate group, changes in forced vital capacity in 12 months were significantly different between before and after nintedanib administration (−253 ± 163 vs −125 ± 235 mL; p = 0.0027). In contrast, changes in forced vital capacity in 12 months were not significantly changed by nintedanib treatment in the severe group (−353 ± 250 vs −112 ± 341 mL; p = 0.2374). Incidence of acute exacerbation was higher in the severe group than in the moderate group (30.8% vs 18.9%). The overall survival of the moderate and the severe groups was 17.2 and 10.1 months.

Conclusion:

In real-world practice, nintedanib showed comparable efficacy to those observed in previous trials. In the severe group, the efficacy of nintedanib might be limited.

Subject Preferences and Psychological Implications of Portable Oxygen Concentrator Versus Compressed Oxygen Cylinder in Chronic Lung Disease

BACKGROUND

Oxygen therapy represents the elective therapy to improve the quality of life for patients with chronic respiratory diseases like COPD and interstitial lung disease. Lightweight portable oxygen concentrators (POCs) are a valid alternative to traditional systems such as portable compressed oxygen cylinders. However, patient preference and the possible psychological implications related to the use of both devices have been poorly assessed. We sought to evaluate patient preference between the ambulatory oxygen systems (ie, a POC or a small cylinder) for patients with COPD and interstitial lung disease experiencing exertional desaturation in a rehabilitation setting. Furthermore, the use of one device in comparison with the other was related to specific mechanical characteristics and related to perceived quality of life, anxiety, and depressive symptoms.

METHODS

30 subjects with COPD and interstitial lung disease, who demonstrated exertional desaturation on room air during 6-min walk test (6MWT), were recruited. Each subject performed 2 6MWTs, in random order: one breathing oxygen via a POC and one with a portable compressed oxygen cylinder. Both devices were set up to ensure oxyhemoglobin saturation between 92% and 95% during the 6MWTs. All subjects completed a questionnaire assessing anxiety, depression, and quality of life. Each device was randomly assigned to each subject for 1 week, and then replaced with the other in the following week. At the end of the trial period, all subjects completed a questionnaire evaluating several aspects of the oxygen therapy devices.

RESULTS

There were no significant differences in oxygen saturation or the mean distances achieved during the 6MWTs between the 2 portable oxygen devices. The subjects expressed greater preference for the POC (73.3%), basing their choice mainly on ease of transport and lower weight. Subjects' age also correlated with preferences: younger subjects were more negatively focused on the weight of the portable compressed oxygen cylinder, whereas older subjects considered the POC easier to manage. No significant differences in preferences were present between COPD and interstitial lung disease.

CONCLUSIONS

The POC and the portable compressed oxygen cylinder performed in a comparable manner during 6MWT for subjects with COPD and interstitial lung disease and exertional desaturation. Subjects preferred the POC because it was associated with better mobility.

Survival and end-of-life aspects among subjects on long-term noninvasive ventilation

Background

The need for noninvasive ventilation (NIV) is commonly considered a predictor of poor survival, but life expectancy may vary depending on the underlying disease. We studied the factors associated with decreased survival and end-of-life characteristics in an unselected population of subjects starting NIV.

Methods

We conducted a retrospective study including 205 subjects initiating NIV from 1/1/2012-31/12/2015 who were followed up until 31/12/2017.

Results

The median survival time was shorter in subjects needing help with activities of daily living than in independent subjects (hazard ratio (HR) for death 1.7, 95% CI 1.2–2.6, P = 0.008) and was also shorter in subjects on long-term oxygen therapy (LTOT) than in those not on LTOT (HR for death 2.8, 95% CI 1.9–4.3, P < 0.001). There was marked difference in survival according to the disease necessitating NIV, and subjects with amyotrophic lateral sclerosis or interstitial lung disease seemed to have the shortest survival. The two most common diseases resulting in the need for NIV were chronic obstructive pulmonary disease (COPD) and obesity hypoventilation syndrome (OHS). The median survival time was 4.4 years in COPD subjects, but the median survival time was not reached in subjects with OHS (HR for death COPD vs. OHS: 3.2, 95% CI 1.9–5.5, P < 0.001). Most of the deceased subjects (55.6%) died in the hospital, while only 20.0% died at home. The last hospitalization admission leading to death occurred through the emergency room in 44.4% of the subjects.

Conclusions

Survival among subjects starting NIV in this real-life study varied greatly depending on the disease and degree of functional impairment. Subjects frequently died in the hospital after admission through the emergency department. A comprehensive treatment approach with timely advance care planning is therefore needed, especially for those needing help with activities of daily living and those with both NIV and LTOT.

Usefulness of Measurement of End-tidal CO2 Using a Portable Capnometer in Patients with Chronic Respiratory Failure Receiving Long-term Oxygen Therapy

Objective Patients with chronic respiratory failure requiring long-term oxygen therapy (LTOT) are at a risk of CO₂ retention because of excessive oxygen administration. The CapnoEye™ is a novel portable capnometer that can measure end-tidal CO₂ (EtCO₂) noninvasively. This retrospective study evaluated the usefulness of this device. Methods EtCO₂ was measured using the CapnoEye™. The EtCO₂ and partial pressure of venous carbon dioxide (PvCO₂) were analyzed, and other clinical data were assessed. Patients Sixty-one consecutive patients with chronic respiratory failure receiving LTOT in the outpatient department at the Japanese Red Cross Medical Center between July 2017 and March 2018 were retrospectively reviewed. Results There was a significant correlation between EtCO₂ and PvCO₂ (r=0.63) in the total study population as well as in the COPD group (r=0.65) and ILD group (r=0.67). The PvCO₂ and EtCO₂ gradient was correlated with only the body mass index in a multivariate analysis (p=0.0235). The EtCO₂ levels on the day of admission were significantly higher than those in the same patients when they were in a stable condition (p=0.0049). There was a significant correlation between ΔEtCO₂ and ΔPvCO₂ (r=0.4). A receiver-operating characteristic curve analysis revealed the optimal cut-off EtCO₂ value for identifying hypercapnia to be 34 mmHg (p=0.0005). Conclusion The evaluation of EtCO₂ by the CapnoEye™ was useful for predicting PvCO₂. The body mass index was identified as a possible predictor of the PvCO₂ and EtCO₂ gradient. An increase in EtCO₂ may indicate deterioration of the respiratory status in patients with chronic respiratory failure receiving LTOT.

Evaluation of a Novel Ear Pulse Oximeter: Towards Automated Oxygen Titration in Eyeglass Frames

Current oxygen delivery modes lack monitoring and can be cumbersome for patients with chronic respiratory diseases. Integrating a pulse oximeter and nasal oxygen cannulas into eyeglasses would reduce the burden of current solutions. An ear pulse oximeter (OxyFrame) was evaluated on 16 healthy volunteers and 20 hypoxemic patients with chronic respiratory diseases undergoing a prespecified protocol simulating daily activities. Correlation, error, and accuracy root mean square error (ARMS) were calculated to compare SpO2 measured by OxyFrame, a standard pulse oximeter (MASIMO), and arterial blood gas analysis (aBGA). SpO2 measured by OxyFrame and MASIMO correlated strongly in volunteers, with low error and high accuracy (r = 0.85, error = 0.2 ± 2.9%, ARMS = 2.88%). Performances were similar in patients (r = 0.87, error 0 ± 2.5%, ARMS = 2.49% compared with MASIMO; and r = 0.93, error = 0.4 ± 1.9%, ARMS = 1.94% compared with aBGA). However, the percentage of rejected measurements was high (volunteers 77.2%, patients 46.9%). The OxyFrame cavum conchae pulse oximeter was successfully evaluated, and demonstrated accurate SpO2 measurements, compliant with ISO 80601-2-61:2017. Several reasons for the high rejection rate were identified, and potential solutions were proposed, which might be valuable for optimization of the sensor hardware.

Randomized cross-over trial of demand oxygen delivery system

INTRODUCTION

Long-term oxygen therapy is reported to improve hypoxemia and survival in patients with respiratory failure. The demand oxygen delivery system (DODS) saves oxygen and extends the usable time of an oxygen cylinder 2- to 3-fold. A portable oxygen concentrator with an auto-DODS has been developed to switch its sensitivity among 3 levels (standard, high, and extra high) and to supply pulsed-flow oxygen when it detects apnea. The aim of this study is to evaluate the efficacy of this newly developed portable oxygen concentrator with auto-DODS compared to the efficacy of conventional DODS in oxygenation.

METHODS AND ANALYSIS

Twenty-six patients with chronic obstructive pulmonary disease or interstitial pneumonia will be randomized to use auto-DODS or conventional DODS at rest and during a 6-minute walk test. Primary endpoints are mean oxygen saturation (SpO2) at rest and during the 6-minute walk test. Secondary endpoints are the ratios of the times during which the oxygen concentrator operates at each sensitivity mode (standard, high, and extra high) and at a constant pulse rate to the examination time, the ratio of the times during which SpO2 fall below 90% to the examination time, the lowest value of SpO2 during the examination time, the mean and highest pulse rates during the examination time, 6-minute walking distance, recovery time, Borg scale, comfort, and reliability, which are measured by a numerical rating scale and a questionnaire, respectively.

ETHICS AND DISSEMINATION

The study was conducted in accordance with the Declaration of Helsinki and was registered on Aug 23, 2019 (https://jrct.niph.go.jp/en-latest-detail/jRCTs052190041). The results of the study will be presented at academic conferences and submitted to a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

jRCTs052190041.

A Retrospective Observational Study of Domiciliary Oxygen Usage in a Subset of Veterans

BACKGROUND

Long-term oxygen therapy (LTOT) delivered continuously is known to decrease mortality in patients with COPD and who are hypoxemic; however, supportive data for LTOT use in patients without COPD is lacking. In addition, many patients may be prescribed LTOT without a definitive etiology for hypoxemia. First, we investigated the diagnoses for which oxygen was prescribed to a sample of veterans and whether each diagnosis was supported by confirmatory testing. Second, we looked at the proportion of subjects who were prescribed non-continuous therapy.

METHODS

We retrospectively studied subjects prescribed domiciliary oxygen at the Veterans Administration Western New York Healthcare System. The subjects who met inclusion criteria were identified by using a computerized patient record system; data were collected on subject characteristics, oxygen prescription information, diagnosis for hypoxia, and diagnostic workup. Descriptive data were presented as mean ± SD and median (range). Statistical analysis was performed by using the chi-square test and an unpaired t test.

RESULTS

A total of 494 subjects were included: 96.8% men, mean ± SD ages 74.2 ± 10.8 y. Most of the subjects were prescribed oxygen as out-patients (68.5%). A total of 335 (67.8%) were prescribed oxygen for continuous therapy, 72 (14.1%) for nocturnal therapy, 50 (10.1%) for exertion, and 30 (6.1%) for both exertion and nocturnal use. At 3 months, 19.6% of the initial cohort had oxygen discontinued. In those subjects with oxygen continued at 3 months, COPD was the most common diagnosis (63.6%), of which 76.1% had pulmonary function tests (PFTs), with 85.7% showing obstruction on spirometry.

CONCLUSIONS

Results of our study showed a 99.4% adherence to Medicare criteria for domiciliary oxygen prescription. Also, 30.3% of the subjects were prescribed LTOT for exertional or nocturnal desaturation or both. Repeated testing at 3 months identified subjects who no longer required oxygen. COPD was the most common etiology for domiciliary oxygen. A small proportion of the subjects (6.9%) were prescribed oxygen without underlying etiology for hypoxia. Exertional and/or nocturnal oxygen prescription was common, and further research to elucidate its utility is clearly warranted.

Long-term oxygen therapy-related adverse outcomes resulting in hospitalisation: 3-year experience of an Australian metropolitan health service

The aim of this study was to evaluate the incidence of long-term oxygen therapy (LTOT)-related adverse outcomes in our health service. LTOT patients retrospectively recruited had their medical records reviewed for the period of 1 January 2014 to 30 June 2018. Burns, physical injuries, any falls attributable to LTOT requiring admission were the outcomes measured. Of 291 patients, four patients required admission due to LTOT-related adverse events where three admissions were related to falls secondary to tripping over oxygen tubing.

Psychosocial Interventions for Patients with Severe COPD-An Up-to-Date Literature Review

Background and Objectives: Chronic obstructive pulmonary disease (COPD) is a life limiting condition with a long list of serious psychosocial consequences, aggravating with illness progression. In advanced stages, chronic respiratory failure often develops, which might undermine mental health and reduce activity. The study objective was to review the recent studies concerning psychosocial interventions dedicated to patients with severe COPD. Materials and Methods: The PubMed database was searched for terms, such as ‘COPD and long-term oxygen therapy, non-invasive ventilation, severe or respiratory failure’ and ‘psychological or psychosocial or mental health and intervention.’ Studies were included that described patients with stable, severe COPD and the outcomes of psychosocial interventions. Results and Conclusions: Thirty-four studies were identified and divided into four thematic groups: home medical support, exercise, self-management and mental health. The number of studies that focused on mental health preservation in severe COPD was very limited; i.e., none refer directly to those treated with respiratory failure. Improving patients’ self-efficacy gave promising effects to the acceptance of palliative care, pulmonary rehabilitation completion and mental health. Physical activity might be recommended to be included in interventions for mental health enhancement, although little is known about the role of the particular forms of exercise. An increasing beneficial use of new technologies for psychosocial interventions was noted. Psychosocial interventions applied in advanced COPD underline the roles of self-efficacy, telehealth and physical activity in physical and mental health preservation. However, all of the above elements need to be independently tested on more homogenous groups of patients and have the possible modes of their treatment analysed.

Pulmonary hypertension with a low cardiac index requires a higher PaO2 level to avoid tissue hypoxia

BACKGROUND AND OBJECTIVE

The optimal oxygen supplementation needed to avoid tissue hypoxia in patients with pulmonary hypertension (PH) remains unclear. This study aimed to identify the arterial oxygen tension (PaO₂ ) level needed to avoid tissue hypoxia which results in a poor prognosis in patients with PH.

METHODS

We retrospectively analysed the data for 1571 right heart catheterizations in patients suspected of having PH between 1983 and 2017 at our institution. Examinations were classified according to mean pulmonary arterial pressure (mPAP), cardiac index (CI) and the presence of lung disease, pulmonary arterial hypertension (PAH) or chronic thromboembolic PH (CTEPH). The PaO₂ levels needed to avoid tissue hypoxia were compared in each subgroup.

RESULTS

The estimated PaO₂ equivalent to a mixed venous oxygen tension (PvO₂ ) of 35 mm Hg (tissue hypoxia) was 63.2 mm Hg in all patients, 77.0 mm Hg in those with decreased CI (<2.5 L/min/m² ) and 57.0 mm Hg in those with preserved CI. Multivariate regression analysis identified mPAP, CI and PaO₂ to be independent predictors of extremely low PvO₂ . Similar results were observed regardless of the severity of PH or the presence of lung disease, PAH or CTEPH. The PaO₂ level needed to avoid tissue hypoxia was higher in patients with mild PH and decreased CI than in those with severe PH and preserved CI (70.2 vs 61.5 mm Hg).

CONCLUSION

These findings indicate that a decreased CI rather than increased mPAP induces tissue hypoxia in PH. Patients with PH and decreased CI may need adjustment of oxygen therapy at higher PaO₂ levels compared with patients with preserved CI.

Pulmonary rehabilitation, physical activity, respiratory failure and palliative respiratory care

The CIRO Academy in Horn (the Netherlands) organised a 2-day meeting to present and discuss the studies published in 2017 pertaining to key priority areas of respiratory and critical care medicine. This review summarises studies focussing on pulmonary rehabilitation and exercise training, physical activity, chronic respiratory failure and palliative respiratory care published in 2017.

Oxygen Therapy in COPD

Long-term oxygen therapy (LTOT) at home has been demonstrated to improve survival in patients with COPD and severe resting hypoxemia. Support for LTOT is based on 2 landmark trials published nearly 4 decades ago. These results form the basis for reimbursement and prescription of LTOT to this day. Recent work has demonstrated no outcome benefit of LTOT in stable COPD patients with moderate desaturation at rest or during activity. Oxygen therapy during activity and exercise has been shown to alleviate symptoms and maintain arterial oxygen saturation, but not improve long-term outcomes. Oxygen therapy in COPD has a number of physiologic, functional, and biologic effects, not all of which are completely understood. Oxygen therapy in exacerbations of COPD can be both helpful and harmful. New guidance on the use of oxygen therapy during pre-hospital care has been published in the United Kingdom. Technology for LTOT represents a challenge for physicians writing prescriptions, durable medical equipment suppliers, caregivers, and patients. New technology for automated control of LTOT shows promise but is hampered by regulatory processes and cost pressures. Recent changes in government reimbursement for home oxygen therapy also present challenges. This paper will review the current evidence regarding LTOT in COPD and the impact on mortality and functional outcomes as well as reviewing technological challenges.

Post-Hospitalization Short-Term Oxygen Therapy: Use of a Clinical Management Pathway and Long-Term Follow-Up

BACKGROUND

Home oxygen therapy is commonly prescribed for patients who remain hypoxemic at hospital discharge, although evidence supporting this practice is lacking. This study aimed to evaluate oxygen prescription and follow-up for patients who were prescribed post-discharge short-term oxygen therapy (STOT) and to assess their long-term outcome.

METHODS

A retrospective audit was undertaken of subjects prescribed STOT following hospitalization at a single site in Melbourne, Australia, between January 2011 and December 2015. During the study period, a designated clinical pathway for STOT prescription and follow-up after hospital discharge was in place. Chart review was performed to collect subject demographics and comorbidities, results of oxygen assessment (arterial blood gas and 6-min walk tests) and prescription, and results at follow-up re-assessment and mortality.

RESULTS

Over five 5 years, 205 subjects were prescribed STOT upon hospital discharge. Common indications for oxygen treatment were chronic lung disease (54%) and dyspnea palliation (26%). Of the 152 subjects who were discharged with non-palliative oxygen therapy, 28% did not fulfil the recommended prescribing criteria or did not have recommended assessments. Among the 118 subjects who returned for re-assessment 4 weeks after initial oxygen provision, 47 (40%) did not fulfill criteria for long-term oxygen therapy. The 1-y cumulative survival rate for the study population was 56%.

CONCLUSIONS

A significant proportion of subjects who were prescribed post-discharge STOT did not fulfill the recommended prescribing criteria. The long-term prognosis for subjects who were prescribed post-discharge STOT was poor.

The effects of health education given by nurses to COPD patients on the daily oxygen concentrator usage time

INTRODUCTION

Long-term oxygen therapy is the most effective method which has been shown to prolong the lifespan in people with COPD. The aim of the study was to investigate the effects of health education given by nurses to patients with COPD on the daily oxygen concentrator (OC) usage time.

MATERIAL AND METHODS

The study was carried out in a State Hospital, Turkey, between July and November 2015. After given consent to the study, participants were divided into intervention and control groups by simple random sampling method. Then data forms were filled during face-to-face interview. Firstly, the data describing patients' arrival times were collected retrospectively. Afterwards, the patients from the intervention group were educated through educational booklets prepared by the researchers. They were phoned in the weeks 4, 8 and 12th for problems they might have encountered during the use of OC. After the 14th week, data forms of patients from the both groups were filled again; the results were compared with previous clinical findings. Data were analysed using SPSS 15.0 for Windows.

RESULTS

It was determined that 95.5% of patients did not get information about the use of OC. Daily OC usage time (hour) by patients in the intervention group firstly amounted to 5.69 ± 3.90, later on to 11.94 ± 4.73 (p < 0.05). Whereas when clinical findings concerning pre- and post educational periods were compared; a significant improvement in PaO₂, PaCO2, FEV₁ and SaO₂ of patients in the intervention group (p<0.05) was shown, contrary to the control group.

CONCLUSIONS

It may be recommended that patients receive continuous education and close monitoring of their results.

Instability of nocturnal parasympathetic nerve function in patients with chronic lung disease with or without nocturnal desaturation

Objective/background

This study was performed to evaluate the association of nocturnal autonomic nerve (AN) dysfunction, especially parasympathetic nerve (PN) function instability, and nocturnal oxygen desaturation (NOD) in patients with chronic lung diseases (CLD).

Patients and methods

Twenty-nine stable CLD patients with irreversible pulmonary dysfunction and mild-to-moderate daytime hypoxemia, 13 CLD patients receiving long-term oxygen therapy (LTOT) with maintained SpO₂ >90%, and 17 senior healthy volunteers underwent two-night examinations of nocturnal AN function by pulse rate variability (PRV) instead of heart rate variation using a photoelectrical plethysmograph simultaneously monitoring SpO₂ and the presence of sleep disordered breathing at home. AN function was examined by instantaneous time–frequency analysis of PRV using a complex demodulation method.

Results

There were no significant differences in mean low frequency/high frequency (HF) ratio (index of sympathetic nerve activity) or mean HF amplitude (index of PN activity) among controls and CLD patients with and without NOD (defined as SpO₂ <90% for at least 3% of total recording time at night). However, the relative times over which the same main HF peak was sustained for at least 20 seconds (%HF_20sec) and 5 minutes in total recording time, indexes of PN function stability, were significantly reduced in CLD patients compared with controls, and further decreased in CLD patients with NOD compared with non-NOD. %HF_20sec was significantly higher in the LTOT group than the NOD group. Furthermore, PaO₂ at rest and nocturnal hypoxia were significantly correlated with PN function instability in CLD patients.

Conclusion

PN function is unstable at night associated with nocturnal hypoxemia in CLD patients, which may reflect poor quality of sleep.

Daily duration of long-term oxygen therapy and risk of hospitalization in oxygen-dependent COPD patients

Introduction

Long-term oxygen therapy (LTOT) improves survival and may reduce hospital admissions in patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia, but the impact of daily duration of LTOT on hospitalization rate is unknown. We aimed to estimate the association between the daily duration of LTOT (24 vs 15 h/d) and hospital admissions in patients with LTOT due to COPD.

Materials and methods

A population-based, cohort study included patients who started LTOT due to COPD between October 1, 2005 and June 30, 2009 in the Swedish national register for respiratory failure (Swedevox). Time to first hospitalization from all causes and from respiratory or nonrespiratory disease, using the National Patient Registry, was analyzed using Fine-Gray regression, adjusting for potential confounders.

Results

A total of 2,249 patients with COPD (59% women) were included. LTOT 24 h/d was prescribed to 539 (24%) and LTOT 15-16 h/d to 1,231 (55%) patients. During a median follow-up of 1.1 years (interquartile range, 0.6-2.1 years), 1,702 (76%) patients were hospitalized. No patient was lost to follow-up. The adjusted rate of all-cause hospitalization was similar between LTOT 24 and 15-16 h/d (subdistribution hazard ratio [SHR] 0.96; [95% CI] 0.84-1.08), as was cause-specific hospitalizations analyzed for respiratory disease (SHR: 1.00; 95% CI: 0.86-1.17) and nonrespiratory disease (SHR: 0.92; 95% CI: 0.75-1.14).

Conclusion

LTOT prescribed for 24 h/d was not associated with decreased hospitalization rates compared with LTOT for 15-16 h/d in patients with oxygen-dependent COPD. The results should be validated in a randomized controlled trial.

Chinese version of the severe respiratory insufficiency questionnaire for patients with COPD receiving long-term oxygen therapy

Purpose

Patients with advanced-stage COPD often experience severe hypoxemia. Treatment with long-term oxygen therapy (LTOT) may relieve patients' symptoms and increase survival. As COPD is incurable, improving patients' health-related quality of life is important. The Chinese version of the Severe Respiratory Insufficiency Questionnaire (SRI) is valid for patients with hypercapnic COPD undergoing noninvasive positive airway pressure ventilation at home. However, the reliability and validity of the Chinese SRI for patients with COPD undergoing LTOT have not been investigated.

Patients and methods

We analyzed reliability using Cronbach's α coefficient. Construct validity was assessed with principal, exploratory, and confirmatory factor analysis. Concurrent validity was evaluated through the correlation between SRI domains and Chronic Respiratory Disease Questionnaire (CRQ) domains. Content validity was assessed by calculating the correlation between each SRI item score and the total score for the relevant domain.

Results

In total, 161 patients participated in this study. The Cronbach's α coefficient for all SRI domains was >0.7, except for the attendant symptoms and sleep domain. Exploratory and confirmatory factor analysis showed a good model fit for each domain, but the factors extracted from each domain were correlated. SRI and CRQ domains correlated well with respect to similar aspects of health-related quality of life, indicating good concurrent validity. Content validity was indirectly shown by a good correlation between each item score and the total score of the relevant domain.

Conclusion

The Chinese version of the SRI has a good reliability and validity for patients with COPD undergoing LTOT in China.

Modification of oxygen concentrators based on questionnaire survey

BACKGROUND

In this study, we conducted a questionnaire survey to clarify and improve problems related to oxygen concentrators.

METHODS

Using a questionnaire survey of 30 patients receiving long-term oxygen therapy for chronic respiratory failure, we investigated the necessity of using a remote controller, portability, fire prevention system, built-in battery type and so on. Patients were divided into two groups according to age, sex, underlying conditions and amount of oxygen prescribed, then analyzed accordingly.

RESULTS

Mean age was 72.3 ± 8.09 years. The mean flow rate for prescribed oxygen was 1.10 L/min at rest and 2.96 L/min under exertion. Median duration of use was 17.5 months. Built-in battery type, environmentally friendly system and voice guidance system received the most attention according to four-grade evaluations of each function. Significant differences were seen in design features in patients less than 72 years old (P = .03), in voice guidance system in patients who only used the equipment during exertion (P = .01), and in brand imaging in those using the equipment under exertion at a flow ≥3 L/min (P = .04). In questionnaire results for the three most desired features, built-in battery type was of primary concern, followed by portability and use of a remote control.

CONCLUSIONS

Overall, built-in battery type, portability, use of a remote control and an environmentally friendly system were desired features for oxygen concentrators. Desired features could vary according to age and the amount of oxygen prescribed.

The influence of disease severity and lifestyle factors on the peak annual 25(OH)D value of COPD patients

Background

The prevalence of individuals deficient in vitamin D (defined as a serum level of the stable metabolite 25(OH)D <50 nmol/L) is increasing in countries with low annual ultraviolet (UV) radiation and among individuals unable to perform outdoor activities, for example, COPD patients.

Objective

To assess the role of vitamin D deficiency, independently of seasonal variation, the peak annual value of 25(OH)D was measured in subjects with advanced COPD ± long-term oxygen therapy (LTOT) and lung healthy control subjects. A method to grade the individual annual UV light exposure was designed and tested.

Subjects and methods

Sixty-six Caucasians with advanced COPD (28 with LTOT) and 47 control subjects were included, and the levels of 25(OH)D were determined in late summer/early fall when the annual peak was assumed. Questionnaires about COPD symptoms, general health, lifestyle, dietary habits and QoL were used to collect data. Lung function tests and blood sampling were performed.

Results

The peak annual 25(OH)D of COPD subjects was significantly lower than in the control subjects, but there was no significant difference between COPD patients with and without LTOT. Ongoing vitamin D supplementation was the single most important intervention to maintain 25(OH)D levels ≥50 nmol/L. Among vitamin D-deficient COPD subjects, 25(OH) D correlated positively with forced expiratory volume in 1 second as % predicted, Modified British Medical Research Council score, blood oxygenation, food portion size, Mediterranean Diet Score and Ultraviolet Score.

Conclusion

Vitamin D deficiency was common among healthy individuals and COPD subjects. Peak annual 25(OH)D levels of COPD subjects correlated with clinically important outcomes. The present study emphasizes the need to routinely monitor vitamin D status among patients with advanced COPD and to consider to medicate those with vitamin D deficiency with vitamin D supplementation.

Adherence to long-term oxygen therapy in patients with chronic obstructive pulmonary disease

Long-term oxygen therapy (LTOT) has beneficial effects on survival in patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia at rest. Two landmark trials suggested that these benefits depend on the time of exposure to oxygen. Patients are usually prescribed LTOT for at least 15–18 hours/day. The primary objective of this study was to determine the average daily exposure to supplemental oxygen in patients with severely hypoxemic COPD who were newly prescribed LTOT and the proportion of patients who were adherent to their prescription. The secondary objective was to identify predictors of compliance to LTOT. We performed a retrospective observational study of patients newly registered in a regional home oxygen program in Quebec, Canada, between July 1, 2013, and December 31, 2014. Daily exposure to oxygen was objectively measured from the concentrator’s counter clock. From 196 patients registered in the program during the study period, 115 contributed to the analysis. Most patients (n = 84; 73%) were prescribed oxygen for ≥18 hours/day. Overall, the 115 patients were exposed to home oxygen for 17.8 hours/day; 60% of the patients were compliant according to our definition. Increasing age and ambulatory oxygen utilization predicted adherence to oxygen therapy. Adherence to home oxygen therapy is suboptimal. Behavioral and psychological interventions to improve compliance to LTOT should be investigated.

Long-term oxygen therapy in COPD patients: population-based cohort study on mortality

Purpose

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide and is associated with a growing and substantial socioeconomic burden. Long-term oxygen therapy (LTOT), recommended by current treatment guidelines for COPD patients with severe chronic hypoxemia, has shown to reduce mortality in this population. The aim of our study was to assess the standardized mortality ratios of incident and prevalent LTOT users and to identify predictors of mortality.

Patients and methods

We conducted a 2-year follow-up population-based cohort study comprising all COPD patients receiving LTOT in the canton of Bern, Switzerland. Comparing age- and sex-adjusted standardized mortality ratios, we examined associations between all-cause mortality and patient characteristics at baseline. To avoid immortal time bias, data for incident (receiving LTOT <6 months) and prevalent users were analyzed separately.

Results

At baseline, 475 patients (20% incident users, n=93) were receiving LTOT because of COPD (48/100,000 inhabitants). Mortality of incident and prevalent LTOT users was 41% versus 27%, respectively, p<0.007, and standardized mortality ratios were 8.02 (95% CI: 5.64–11.41) versus 5.90 (95% CI: 4.79–7.25), respectively. Type 2 respiratory failure was associated with higher standardized mortality ratios among incident LTOT users (60.57, 95% CI: 11.82–310.45, p=0.038).

Conclusion

Two-year mortality rate of COPD patients on incident LTOT was somewhat lower in our study than in older cohorts but remained high compared to the general population, especially in younger patients receiving LTOT <6 months. Type 2 respiratory failure was associated with mortality.

Oxidant status, iron homeostasis, and carotenoid levels of COPD patients with advanced disease and LTOT

Background: The pathogenesis of chronic obstructive pulmonary disease (COPD) is associated with oxidative stress. Both iron (Fe) and oxygen are involved in the chemical reactions that lead to increased formation of reactive oxygen species. Oxidative reactions are prevented by antioxidants such as carotenoids.

Objective: To study the differences in Fe status, carotenoid levels, healthy eating habits, and markers of inflammation and oxidative damage on proteins in subjects with severe COPD ± long-term oxygen therapy (LTOT) and lung-healthy control subjects.

Methods: Sixty-six Caucasians with advanced COPD (28 with LTOT) and 47 control subjects were included. Questionnaires about general health, lifestyle, and dietary habits were answered. Lung function tests and blood sampling were performed.

Results: COPD subjects (±LTOT) did not demonstrate increased oxidative damage, assessed by protein carbonylation (PC), while levels of soluble transferrin receptors (sTfRs) were slightly elevated. Soluble TfRs, which is inversely related to Fe status, was negatively associated with PC. Levels of carotenoids, total and β-cryptoxanthin, α- and β-carotenes, were significantly lower in COPD subjects, and their diet contained significantly less fruits and vegetables. Lutein correlated inversely with IL-6, lycopene correlated inversely with SAT, while β-carotene was positively associated with a Mediterranean-like diet.

Conclusions: Fe could favor oxidative stress in COPD patients, suggesting a cautious use of Fe prescription to these patients. COPD subjects ate a less healthy diet than control subjects did and would, therefore, benefit by dietary counseling. COPD patients with hypoxemia are probably in particular need of a lycopene-enriched diet.

Major Depression in Long-Term Oxygen Therapy Dependent Chronic Obstructive Pulmonary Disease

PURPOSE

We aimed to investigate the frequency of major depression (MD) in long-term oxygen therapy (LTOT) dependent chronic obstructive pulmonary disease (COPD) patients and the effect of depression on patients' compliance with the treatment.

DESIGN AND METHODS

Fifty-four consecutive patients were enrolled in the study and diagnosed as stage 4 COPD according to Global Initiative for Chronic Obstructive Lung Disease guideline. MD was diagnosed with the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition/Clinical Version.

FINDINGS

Thirty-four (63.0%) patients had MD. MD frequency was significantly higher in patients who were noncompliant with LTOT compared with compliant patients.

PRACTICE IMPLICATIONS

MD is a common psychiatric disorder in COPD patients receiving LTOT.

Real-life feasibility and effectiveness of home-based pulmonary rehabilitation in chronic obstructive pulmonary disease requiring medical equipment

Background

Pulmonary rehabilitation (PR) is a key treatment of chronic obstructive pulmonary disease (COPD) but studies are still needed to identify the most pertinent criteria to personalize this intervention and improve its efficacy.

Objective

This real-life retrospective study compared the effects of home-based PR on exercise tolerance, anxiety, depression, and health-related quality of life (HRQoL) in COPD patients, according to their medical equipment.

Methods

Exercise tolerance, anxiety, depression, and HRQoL were evaluated in 109 patients equipped with long-term oxygen therapy (LTOT), 84 patients with noninvasive ventilation (NIV), 25 patients with continuous positive airway pressure (CPAP), and 80 patients with no equipment (NE), before, just after, and 6 and 12 months after PR.

Results

At baseline, the body mass index in the CPAP and NIV groups was higher (p<0.05) than in the other two groups, and the forced expiratory volume in 1 second was lower in the LTOT and NIV groups (p<0.001). All parameters improved after PR in the four groups (p<0.05), but for exercise tolerance, only the 6-minute stepper test showed maintained improvement after 6 and 12 months, whereas the 10 times sit-to-stand and timed up-and-go tests were only improved just after PR. At every time point, exercise tolerance was lower in the LTOT group (p<0.05), with a similar trend in the NIV group.

Conclusion

Despite differences in the medical equipment to treat COPD, home-based PR showed comparable feasibility, safety, and efficacy in all equipment-based groups. Medical equipment should therefore not be a barrier to home-based PR.

Lung transplantation and survival outcomes in patients with oxygen-dependent COPD with regard to their alpha-1 antitrypsin deficiency status

Background

Individuals with severe alpha-1 antitrypsin deficiency (AATD) have an increased risk of developing COPD. However, outcomes during long-term oxygen therapy (LTOT) in patients with severe AATD and hypoxemia are unknown.

Patients and methods

This was a prospective, population-based, consecutive cohort study of patients on LTOT due to COPD in the period from January 1, 1987, to June 30, 2015, in the Swedish National Registry for Respiratory Failure (Swedevox). Severe AATD was identified using the Swedish AATD registry and confirmed by isoelectric focusing. Data on lung transplantation (LTx) were obtained from the two lung transplantation centers in Sweden. Mortality and causes of death were assessed based on the National Causes of Death Registry and analyzed using multivariable Cox regression.

Results

A total of 14,644 patients who started LTOT due to COPD were included in this study. No patient was lost to follow up. Patients with AATD were younger, included more males and more never smokers, and had fewer comorbidities. During a median follow-up of 1.6 years (interquartile range [IQR], 2.7) on LTOT, patients without severe AATD had a higher mortality, hazard ratio [HR] 1.53 (95% CI, 1.24–1.88), adjusting for age, sex, smoking status, body mass index, performance status, level of hypoxemia, and comorbidities. Cardiovascular deaths were increased. A higher proportion of AATD patients underwent LTx, 53 (19%) vs 118 (1%). Survival after LTx was similar for AATD and non-AATD patients and was predicted by age.

Conclusion

In oxygen-dependent COPD, patients with severe AATD have a longer survival time on LTOT, but they have a similar prognosis after lung transplantation compared with patients without AATD.

Perceived Satisfaction With Long-Term Oxygen Delivery Devices Affects Perceived Mobility and Quality of Life of Oxygen-Dependent Individuals With COPD

BACKGROUND

Although routine physical activity for individuals with COPD is recommended, there are inherent limitations of available oxygen delivery devices that may result in hypoxemia during activity. Changes in Medicare laws have resulted in an increased use of oxygen cylinders and a reduction in the use of liquid oxygen devices. The aim of this survey was to assess the impact of perceived satisfaction with various oxygen delivery devices on perceived mobility and quality of life (QOL) of oxygen-dependent subjects with COPD.

METHODS

A survey was developed to measure perceived satisfaction with current portable oxygen delivery devices, perceived mobility, and perceived QOL. The survey was deployed via a link posted on the COPD Foundation's COPD360SOCIAL social media site for 5 weeks, which resulted in the recruitment of 529 participants, of which 417 were included in the data analysis.

RESULTS

Quantile regression analysis revealed that the median perceived device satisfaction score was significantly higher in the liquid oxygen device group (P < .001) compared with the portable oxygen cylinder and portable oxygen concentrator (POC) groups. The median perceived mobility score was significantly higher in the liquid oxygen device group (P < .001) compared with the portable oxygen cylinder group, but not the POC group. The median QOL score was significantly higher in the liquid oxygen device group (P < .001) compared with the POC and portable oxygen cylinder groups. Moreover, partial least-squares structural equation modeling regression analysis showed that perceived mobility is significantly affected by perceived satisfaction with the long-term oxygen therapy (LTOT) device (adjusted R² = 0.15, P < .001), and perceived QOL is significantly affected by both perceived satisfaction with the LTOT device and perceived mobility (adjusted R² = 0.45, P < .001).

CONCLUSIONS

For individuals with COPD requiring LTOT, perceived satisfaction with a portable LTOT device significantly and positively affects perceived mobility and QOL.

Effectiveness of home-based exercise in older patients with advanced chronic obstructive pulmonary disease: A 3-year cohort study

AIM

To determine whether home-based exercise can improve clinical outcomes in older patients with advanced chronic obstructive pulmonary disease using long-term oxygen therapy.

METHODS

Information was provided to improve chronic obstructive pulmonary disease self-management before the onset of the present prospective 3-year cohort study. Patients selected either home-based exercise using a lower-limb cycle machine (ergo-bicycle; group E), or usual exercise (group U). To assess self-management, the Lung Information Needs Questionnaire was evaluated every 6 months. Clinical outcomes included the 6-min walk test, pulmonary function tests, the body mass index, airflow obstruction, dyspnea and exercise index, St. George's respiratory questionnaire, and the number of exacerbations and hospitalizations.

RESULTS

A total of 136 patients (group E = 72; group U = 64), with a mean age of 74.2 years were enrolled. Total Lung Information Needs Questionnaire scores improved over 3 years for group E (P = 0.003). The distance of the 6-min walk test was well maintained in group E, but significantly decreased in group U (P < 0.001). The percentage of forced expiratory volume in 1 s at baseline was lower in group E (P = 0.016), but was maintained over 3 years, whereas a significant reduction was seen in group U (P = 0.001). The body mass index, airflow obstruction, dyspnea and exercise index significantly worsened in both groups over 3 years (group E: P = 0.011; group U: P < 0.001), whereas a significant decrease in the number of exacerbations was noted in group E (P = 0.009).

CONCLUSIONS

Patients who undertook home-based exercise using an ergo-bicycle were able to maintain clinical outcomes including 6-min walk test distance and percentage of forced expiratory volume in 1 s predicted, and recorded fewer exacerbations over 3 years. Geriatr Gerontol Int 2018; 18: 42-49.

Home noninvasive positive pressure ventilation with built-in software in stable hypercapnic COPD: a short-term prospective, multicenter, randomized, controlled trial

Background

The benefits of noninvasive positive pressure ventilation (NPPV) in patients with hypercapnic COPD are controversial. It is presumed that methodology and appropriate use of NIV ventilator might be crucial for the outcomes. With the new built-in software, the performance of NIV can be monitored at home, which can guarantee the compliance and appropriate use. This study investigated effects of home use of NIV in hypercapnia in COPD patients using the NIV ventilator with built-in software for monitoring.

Methods

The current multicenter prospective, randomized, controlled trial enrolled patients with stable GOLD stages III and IV hypercapnic COPD. Patients were randomly assigned via a computer-generated randomization sequence, with a block size of four patients, to continue optimized treatment (control group) or to receive additional NPPV (intervention group) for 3 months. The primary outcome was arterial carbon dioxide pressure (PaCO₂). Data were derived from built-in software and analyzed every 4 weeks. Analysis was carried out with the intention to treat. This study is registered with ClinicalTrials.gov, number NCT02499718.

Results

Patients were recruited from 20 respiratory units in China from October 1, 2015, and recruitment was terminated with a record of the vital statistics on May 31, 2016. A total of 115 patients were randomly assigned to the NPPV group (n=57) or the control group (n=58). Patients complied well with NPPV therapy (mean [± standard deviation] day use 5.6±1.4 h). The mean estimation of leaks was 37.99±13.71 L/min. The changes in PaCO₂ (−10.41±0.97 vs −4.32±0.68 mmHg, P=0.03) and 6-min walk distance (6MWD) (38.2% vs 18.2%, P=0.02) were statistically significant in the NPPV group versus the control group. COPD assessment test (CAT) showed a positive trend (P=0.06) in favor of the NPPV group. Pulmonary function and dyspnea were not different between groups.

Conclusion

Ventilators equipped with built-in software provided methodology for monitoring NIV use at home, which could facilitate the improvement of compliance and quality control of NIV use. It was shown that three months use of NIV at home could reduce the PaCO₂ and improve exercise tolerance (6MWD) in chronic hypercapnic COPD patients.

Burn injury during long-term oxygen therapy in Denmark and Sweden: the potential role of smoking

Background

Long-term oxygen therapy (LTOT) increases life expectancy in patients with COPD and severe hypoxemia. Smoking is the main cause of burn injury during LTOT. Policy regarding smoking while on LTOT varies between countries. In this study, we compare the incidence of burn injury that required contact with a health care specialist, between Sweden (a country with a strict policy regarding smoking while on LTOT) and Denmark (a country with less strict smoking policy).

Methods

This was a population-based, cohort study of patients initiating LTOT due to any cause in Sweden and Denmark. Data on diagnoses, external causes, and procedures were obtained from the Swedish and Danish National Patient Registers for inpatient and outpatient care. Patients were followed from January 1, 2000, until the first of the following: LTOT withdrawal, death, or study end (December 31, 2009). The primary end point was burn injury during LTOT.

Results

A total of 23,741 patients received LTOT in Denmark and 7,754 patients in Sweden. Most patients started LTOT due to COPD, both in Sweden (74%) and in Denmark (62%). The rate of burn injury while on LTOT was higher in Denmark than in Sweden; 170 (95% confidence interval [CI], 126–225) vs 85 (95% CI, 44–148) per 100,000 person-years; rate ratio 2.0 (95% CI, 1.0–4.1). The risk remained higher after adjustment for gender, age, and diagnosis in multivariate Cox regression, hazard ratio 1.8 (95% CI, 1.0−3.5). Thirty-day mortality after burn injury was 8% in both countries.

Conclusion

Compared to Sweden, the rate of burn injury was twice as high in Denmark where smoking is not a contraindication for prescribing LTOT.

Thomas L Petty's lessons for the respiratory care clinician of today

Because of the importance of his original contributions and their practical relevance today, Thomas L Petty (1932-2009) was arguably the most important physician in the history of respiratory care. As much as any single individual, he was responsible for the concept of intensive and multidisciplinary respiratory care. In the 1960s and 1970s, he made key observations and introduced pioneering therapies in the ICU and in the home. He was the first to describe and name ARDS and to show how to use PEEP to treat life-threatening hypoxemia. He was one of the first anywhere to organize a pulmonary rehabilitation program and to show the beneficial effects of long-term oxygen therapy in COPD. Dr Petty emphasized the importance of practical, hands-on respiratory care education for both physicians and non-physicians using a collaborative team approach. He targeted educational activities and practical resources specifically to patients, and he showed how researchers and clinicians could interact responsibly with innovators in industry to the benefit of both. His life and career provide 6 important lessons for respiratory clinicians today and in the future: (1) whatever their roles, RTs and other clinicians in this field need to be experts in its core areas, such as mechanical ventilation, ARDS, and COPD; (2) respiratory care is a team activity: every member is important, and all the members need to communicate well and work together; (3) education needs to be targeted to those in the best position to benefit the patient, including primary care providers and family members; (4) everyone in the field needs to understand the important role of the respiratory care industry and to deal with it responsibly; (5) it must never be forgotten that it is all about the patient; and (6) respiratory care should be exciting and fun.

Physical and psychosocial factors associated with physical activity in patients with chronic obstructive pulmonary disease

OBJECTIVES

To assess physical activity and sitting time in patients with chronic obstructive pulmonary disease (COPD) and to investigate which physical and psychosocial factors are associated with physical activity and sitting time.

DESIGN

Cross-sectional study.

SETTING

Patients were recruited at outpatient clinics of general hospitals and from general practitioners.

PARTICIPANTS

Patients (N=113) with mild to very severe COPD.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Physical activity and sitting time were measured with a triaxial accelerometer (24h/d).

RESULTS

Mean locomotion time per 24 hours was 6.8% (range, 0.7%-20.4%). Elevated physical activity was independently associated with higher self-efficacy, higher functional exercise capacity, and lower lung hyperinflation. Decreased physical activity was strongest in more severe stages of COPD, in which the patients were mainly limited by physical disease-specific factors (higher lung hyperinflation, worse dyspnea severity, worse leg muscle function, and oxygen use). In less severe patients, physical activity was independently associated with more generic factors (higher self-efficacy and the spring/summer season). Sitting time did not differ between severity stages, and longer sitting time in the total group was independently associated with more positive perception of treatment control, less autonomous motivation to exercise, not using sleep medication, and oxygen use.

CONCLUSIONS

Both physical and psychosocial factors were associated with physical activity in patients with COPD. The factors associated with physical activity differed between disease severity stages, raising the question of whether physical activity enhancement programs should differ as well. Sitting time should be investigated further.

Long-term oxygen therapy: are we prescribing appropriately?

Long-term oxygen therapy (LTOT) is the treatment proven to improve survival in chronic obstructive pulmonary disease (COPD) patients with chronic respiratory failure. It also appears to reduce the number of hospitalizations, increase effort capacity, and improve health-related quality of life. Standard LTOT criteria are related to COPD patients who have PaO2 < 60 mmHg, are in a clinical stable situation, and are receiving optimal pharmacological treatment. According to LTOT guidelines, oxygen should be prescribed for at least 18 hours per day although some authors consider 24 hours would be more beneficial. The benefits of LTOT depend on correction of hypoxemia. Arterial blood gases should be measured at rest. During exercise, an effort test should be done to assure adequate SaO2. During sleep, continuous monitoring of SaO2 and PaCO2 should be performed to confirm correction of SaO2 overnight. An arterial blood gas sample should be taken at awakening to assess PaCO, in order to prevent hypoventilation from the oxygen therapy. Several issues that need to be addressed are the use of LTOT in COPD patients with moderate hypoxemia, the efficacy of LTOT in patients who desaturate during exercise or during sleep, the optimal dosage of oxygen supplementation, LTOT compliance, and the LTOT prescription in diseases other than COPD.