Home oxygen for moderate hypoxaemia in chronic obstructive pulmonary disease: a systematic review and meta-analysis

Palliative home oxygen: practical framework for clinicians

The British Thoracic Society 2015 guidelines on home oxygen use in adults have been pivotal in guiding clinicians on the use of long-term oxygen therapy in improving survival outcomes for patients. However, guidance for use of home oxygen in the palliative care setting has not been as robust owing to the lack of evidence-based studies. Therefore, this narrative review aims to provide a clinical framework on the use of palliative home oxygen therapy by considering its prognostic and symptomatic benefits as well as offering pragmatic advice for palliative home oxygen in end-of-life care.

Factors Associated With Change in S3-NIV Score Over Time in People With Chronic Respiratory Failure Treated With Long-Term Home Noninvasive Ventilation

INTRODUCTION

Monitoring changes in symptoms over time during long-term nocturnal home non-invasive ventilation (NIV) using patient-reported outcome measures is crucial. This study aimed to identify factors associated with changes in the S3-NIV total score, its two domains ("respiratory symptoms" and "sleep and NIV-related side effects") and individual item responses.

METHODS

We conducted a retrospective, longitudinal data analysis of a cohort of adults with chronic respiratory failure treated with NIV. Data were obtained from a French homecare provider. Multivariate linear and multinomial ordinal mixed effect models were used to identify factors associated with changes in S3-NIV scores over time.

RESULTS

Median follow-up was 2 years for 2135 participants. Each participant completed a median of five S3-NIV questionnaires; totaling 11,359 analyzed questionnaires. Type of respiratory condition, sex, age and time since NIV initiation were associated with change in S3-NIV score over time. NIV adherence was not associated with total S3-NIV score but high adherence was associated with more severe respiratory symptoms and an improvement in sleep and NIV-related side effects during the follow-up. Intensity of pressure support was associated with a lower total S3-NIV score and more side effects. Face masks and supplemental oxygen were associated with a lower S3-NIV total score.

CONCLUSION

Changes in S3-NIV scores over time are associated with the individual's characteristics and NIV settings. Analysis of the two domains and individual items of the S3-NIV could increase understanding of the difficulties experienced by people on NIV.

Hyperoxia and brain: the link between necessity and injury from a molecular perspective

Oxygen (O2) supplementation is commonly used to treat hypoxia in patients with respiratory failure. However, indiscriminate use can lead to hyperoxia, a condition detrimental to living tissues, particularly the brain. The brain is sensitive to reactive oxygen species (ROS) and inflammation caused by high concentrations of O2, which can result in brain damage and mitochondrial dysfunction, common features of neurodegenerative disorders. Hyperoxia leads to increased production of ROS, causing oxidative stress, an imbalance between oxidants and antioxidants, which can damage tissues. The brain is particularly vulnerable to oxidative stress due to its lipid composition, high O2 consumption rate, and low levels of antioxidant enzymes. Moreover, hyperoxia can cause vasoconstriction and decreased O2 supply to the brain, posing a challenge to redox balance and neurodegenerative processes. Studies have shown that the severity of hyperoxia-induced brain damage varies with inspired O2 concentration and duration of exposure. Therefore, careful evaluation of the balance between benefits and risks of O2 supplementation, especially in clinical settings, is crucial.

Chronic obstructive pulmonary disease (COPD) and COPD-like phenotypes

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease. Historically, two COPD phenotypes have been described: chronic bronchitis and emphysema. Although these phenotypes may provide additional characterization of the pathophysiology of the disease, they are not extensive enough to reflect the heterogeneity of COPD and do not provide granular categorization that indicates specific treatment, perhaps with the exception of adding inhaled glucocorticoids (ICS) in patients with chronic bronchitis. In this review, we describe COPD phenotypes that provide prognostication and/or indicate specific treatment. We also describe COPD-like phenotypes that do not necessarily meet the current diagnostic criteria for COPD but provide additional prognostication and may be the targets for future clinical trials.

Supplemental oxygen therapy in chronic obstructive pulmonary disease: is less is more? How much is too much?

PURPOSE OF REVIEW

Currently available evidence supporting the use of supplemental oxygen therapy (SOT) in chronic obstructive pulmonary disease (COPD) is complex, and data on the mortality reduction associated with SOT usage in patients with severe daytime resting hypoxemia have not been updated since the development of other treatments.

RECENT FINDINGS

No reduction in mortality was found when SOT was used in patients with moderate resting daytime, isolated nocturnal, or exercise-induced hypoxemia. However, some of these patients obtain other significant benefits during SOT, including increased exercise endurance, and a mortality reduction is possible in these 'responders'. The adverse effects of long-term oxygen therapy also need to be considered, such as reduced mobility and social stigma. Furthermore, conservative SOT could improve outcomes in the setting of COPD exacerbations compared with higher concentration oxygen regimens. Compared with usual fixed-dose SOT, automated oxygen administration devices might reduce dyspnea during exercise and COPD exacerbations.

SUMMARY

Current recommendations for SOT need to be revised to focus on patients who respond best and benefit most from this therapy. A conservative approach to SOT can reduce side effects compared with higher concentration oxygen regimens, and automated oxygen administration devices may help to optimize SOT.

Association between chronic obstructive pulmonary disease and 28-day mortality in patients with sepsis: a retrospective study based on the MIMIC-III database

BACKGROUND

Sepsis is a common cause of mortality in critically ill patients, and chronic obstructive pulmonary disease (COPD) is one of the most common comorbidities in septic patients. However, the impact of COPD on patients with sepsis remained unclear. Therefore, the purpose of this study aimed to assess the effect of COPD on the prognosis of septic patients based on Medical Information Mart for Intensive Care (MIMIC-III) database.

METHODS

In this retrospective study based on the (MIMIC)-III database version 1.4 (v1.4), we collected clinical data and 28-day all-cause mortality from patients with sepsis in intensive care unit (ICU) and these patients met the diagnostic criteria of Sepsis 3 on ICU admission between 2008 and 2012. International Classification of Diseases (ICD-9) (4660, 490, 4910, 4911, 49120, 49121, 4918, 4919, 4920, 4928, 494, 4940, 4941, 496) was used to identified COPD. We applied Kaplan-Meier analysis to compare difference of 28-day all-cause mortality between septic patients with and without COPD. Cox proportional-hazards model was applied to explore the risk factor associated with 28-day all-cause mortality in patients with sepsis.

RESULTS

Six thousand two hundred fifty seven patients with sepsis were included in this study, including 955 (15.3%) patients with COPD and 5302 patients without COPD (84.7%). Compared with patients without COPD, patients with COPD were older (median: 73.5 [64.4, 82.0] vs 65.8 [52.9, 79.1], P < 0.001), had higher simplified acute physiology score II (SAPSII) (median: 40.0 [33.0, 49.0] vs 38.0 [29.0,47.0], P < 0.001) and greater proportion of mechanical ventilatory support (MV) (55.0% vs 48.9%, P = 0.001). In our study, septic patients with COPD had higher 28-day all-cause mortality (23.6% vs 16.4%, P < 0.001) than patients without COPD. After adjusting for covariates, the results showed that COPD was an independent risk factor for the 28-day all-cause mortality of patients with sepsis (HR 1.30, 95%CI: 1.12-1.50, P = 0.001).

CONCLUSIONS

COPD was an independent risk factor of 28-day all-cause mortality in septic patients. Clinically, septic patients with COPD should be given additional care.

Impact of pharmacological and non-pharmacological interventions on mortality in chronic obstructive pulmonary disease (COPD) patients

PURPOSE

This review aimed to summarise evidence about the impact of pharmacological and non-pharmacological interventions on survival in COPD patients.

METHODS

We performed a narrative literature review on the effect of pharmacological and non-pharmacological interventions on survival in COPD patients.

RESULTS

Inhaled therapies are central to reduce symptoms in COPD. In particular, inhaled steroids seem to have the greatest effect on mortality. Despite the anti-inflammatory effects attributed to statins, their benefit in COPD has been shown only in cases of combined cardiovascular diseases. The use of beta-blockers in COPD has not been associated with increased COPD-related mortality and a beneficial effect on all-cause mortality has even been shown in COPD patients with cardiovascular diseases. Influenza and pneumococcal vaccination reduced the occurrence of exacerbations and mortality due to COPD. In addition, long-term oxygen therapy (LTOT) (≥15h/day) in COPD patients with severe hypoxemia had a positive effect on survival. Regarding non-pharmacological interventions, it has been demonstrated that smoking cessation, treatment compliance and nutritional supplementation for underweight patients also have a positive effect on survival. Non-invasive ventilation results were dependent on patient PaCO2 levels. In patients with advanced COPD, further prospective studies are needed to know the effect of bronchoscopic lung volume reduction and lung transplant on COPD survival. Regarding lung transplant, a survival benefit in patients with a pre-transplant BODE score of ≥7 has been shown in retrospective studies.

CONCLUSION

Most of the studies did not evaluate survival as the main criteria and further long-term studies on the global management of COPD are required.

Relationship between nighttime symptoms and clinical features in COPD patients: A cross-sectional multicenter study in China

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease that causes breathing difficulties, coughing, and other symptoms. Nighttime symptoms, such as coughing, wheezing, and shortness of breath, can significantly impact the quality of life for people with COPD.

OBJECTIVE

To investigate the relationship between nighttime symptoms and other clinical features in patients with COPD, and identify potential risk factors associated with nighttime symptoms.

METHODS

This cross-sectional study was conducted from October 1, 2022 to November 30, 2022 in 24 hospital outpatient departments in different cities of Hunan Province, China. The COPD Nighttime Symptom Instrument (NiSCI) was used to measure the severity of night time symptoms in COPD patients. Descriptive and inferential statistics were used to express patient socio-demographics and factors influencing nighttime symptoms.

RESULTS

The study included 2219 COPD patients. The results showed that nighttime symptom scores differed significantly based on gender, whether the patient had experienced acute exacerbation in the past year, mMRC and CAT scores, the duration of home oxygen therapy and home non-invasive ventilation (all P < 0.0001). Multiple linear regression analysis revealed that CAT score (P < 0.0001) was significantly associated with nighttime symptom scores.

CONCLUSION

Nighttime symptoms are prevalent in Chinese COPD patients and correlate with disease severity. The assessment and management of nighttime symptoms in COPD patients must take into account gender, CAT and mMRC scores, history of acute exacerbations, and duration of home oxygen therapy and home non-invasive ventilation to enable tailoring of treatment strategies to individual needs.

Acceptance and adherence to non-invasive positive pressure ventilation in people with chronic obstructive pulmonary disease: a grounded theory study

Introduction

Non-Invasive Positive Pressure Ventilation (NPPV) is an established treatment for people with Chronic Obstructive Pulmonary Disease (COPD), but it is often improperly used or rejected. The patterns of acceptance and adherence to NPPV, conceiving constraints, and strengths related to its adaptation have not been explored from a qualitative perspective yet.

Objectives

This study aims to qualitatively explore patterns of adaptation to NPPV in people affected by COPD and to identify the core characteristics and the specific adaptive challenges during the adaptation process.

Methods

Forty-two people with moderate or severe COPD were recruited and 336 unstructured interviews were conducted. A Constructivist Grounded Theory was used to gather and analyze data: the transcriptions were mutually gathered in open, selective, and theoretical phases, with open, selective, and theoretical coding, respectively.

Results

The analysis resulted in a non-linear and dynamic process, characterized by three phases: deciding, trying NPPV, and using NPPV. The patterns revealed that positive and negative NPPV experiences, together with beliefs, emotions, stressful mental states, and behaviors result in different acceptance and adherence rates.

Discussions

These findings may be helpful to implement new care strategies to promote acceptance and adherence to NPPV.

Contemporary Concise Review 2022: Chronic obstructive pulmonary disease

International respiratory organizations now recommend using lower limit of normal and standardized residuals to diagnose airflow obstruction and COPD though using a fixed ratio <0.7 is simpler and robustly predicts important clinical outcomes. The most common COPD comorbidities are coronary artery calcification, emphysema and bronchiectasis. COPD patients with psychological (high anxiety and depression) and cachectic (underweight and osteoporotic) comorbidity have higher mortality and exacerbate more. Serum eosinophil count remains an important COPD biomarker and we have greater clarity about normal eosinophil levels in COPD and the wider population. Criteria for entry into COPD clinical trials continue to exclude many patients, in particular those at greater risk of exacerbation and death. The effect of hyperinflation on cardiac function impacts COPD mortality and is an important target for successful lung volume reduction procedures.

Oxygen in interstitial lung diseases

Domiciliary oxygen is essential in the care of hypoxaemic interstitial lung disease (ILD) patients. Guidelines concur in advising prescription of long-term oxygen therapy (LTOT) for ILD patients with severe hypoxaemia at rest, in view of its beneficial impact on breathlessness/disability and extrapolating potential survival benefits seen in COPD patients. A less severe hypoxaemia threshold for initiation of LTOT is recommended for patients with pulmonary hypertension (PH)/right heart failure, requiring careful evaluation in all ILD patients. In light of evidence suggesting a link between nocturnal hypoxaemia, development of PH and poor survival, studies assessing the impact of nocturnal oxygen are urgently needed. Severe exertional hypoxaemia is frequent in ILD patients, with impact on exercise tolerance, quality of life and mortality. Ambulatory oxygen therapy (AOT) has been associated with improvement in breathlessness and quality of life in ILD patients with exertional hypoxaemia. However, given the paucity of evidence, not all current AOT guidelines are in agreement. Ongoing clinical trials will provide further useful data. Despite its beneficial effects, supplemental oxygen imposes burdens and challenges to patients. A key unmet area of need is the development of less cumbersome and more efficient oxygen delivery systems to reduce the negative impact of AOT on patients' lives.

Home oxygen monitoring and therapy: learning from the pandemic

PURPOSE OF REVIEW

Home oxygen monitoring and therapy have been increasingly used in the management of patients with chronic diseases. The COVID-19 pandemic has prompted the rapid uptake of remote monitoring programmes to support people with COVID-19 at home. This review discusses the recent evidence and learning in home oxygen monitoring and therapy from the pandemic.

RECENT FINDINGS

Many home oxygen monitoring programmes were established around the world during the pandemic, mostly in high-income countries to support early detection of hypoxaemia and/or early hospital discharge. The characteristics of these programmes vary widely in the type of monitoring (self-monitoring or clinician-monitoring) and the patient risk groups targeted. There is a lack of evidence for benefits on clinical outcomes, including mortality, and on reductions in healthcare utilisation or cost-effectiveness, but programmes are viewed positively by patients. Recent studies have highlighted the potential bias in pulse oximetry in people with darker skin.

SUMMARY

Recent evidence indicates that home oxygen monitoring therapy programmes are feasible in acute disease, but further research is needed to establish whether they improve patient outcomes, are cost-effective and to understand their equity impact.