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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Cognitive Function and the Ability to Operate Long-Term Oxygen Therapy Equipment: An Exploratory Study

Chronic respiratory disease patients with severe hypoxia receive long-term oxygen therapy (LTOT). The proper operation of LTOT equipment is essential for continuing treatment. This exploratory study investigated the relationship between cognitive impairment as a comorbidity in patients receiving LTOT and their ability to operate the LTOT equipment. The study measured responses to questions based on the ability of participants to operate the equipment and applied the Montreal Cognitive Assessment (MoCA). The ability of groups with MoCA scores ≤ 25 and >25 to operate LTOT equipment was compared to confirm the correlation between MoCA and ability to operate the equipment. An aggregate of 60 participants receiving LTOT were recruited, of whom 45 (75%) were MoCA score ≤ 25. The group of MoCA score ≤ 25 demonstrated a lower ability to operate LTOT equipment than group of MoCA score > 25 (p = 0.012). Additionally, a correlation was found between the ability to operate LTOT equipment and MoCA (rs = 0.743, p < 0.001). The results indicated that the group of MoCA score ≤ 25 indicated a lower ability to operate LTOT equipment than that of MoCA score > 25. Cognitive impairment in patients receiving LTOT can affect their ability to operate LTOT equipment.

Adverse Effects, Smoking, Alcohol Consumption and Quality of Life During Long-Term Oxygen Therapy: A Nationwide Study

Rationale

Long-term oxygen therapy (LTOT) is prescribed for at least 15 hours per day and often used by patients for several years, but knowledge is limited regarding adverse effects, risk exposures, and health-related quality of life (HrQoL) among those treated.

Objectives

To determine the prevalence of adverse effects, smoking, and alcohol consumption and their relations to HrQoL among patients treated with LTOT.

Methods

This was a cross-sectional survey of a randomized sample of adults with ongoing LTOT in the Swedish National Registry for Respiratory Failure (Swedevox). Patient characteristics and the prevalence of 26 prespecified adverse effects, smoking, and alcohol consumption, were compared between respondents with better and worse HrQoL on the chronic obstructive pulmonary disease assessment test.

Results

A total of 151 respondents were included (mean age, 74.7 yr [standard deviation, 8.6 yr]; 58.9% women; median LTOT duration, 2.2 yr [interquartile range, 1.0–3.8 yr]). Characteristics upon starting LTOT were similar between respondents and nonrespondents. Active smoking was very rare (n = 4, 2.6%). For alcohol use, 67.2% of participants reported no consumption during an average week, whereas risk use was reported by 25.8% of men and 16.9% of women. The most prevalent adverse effects were reduced mobility or physical activity (70.9%), dry mouth (69.5%), congestion or nasal drip (61.6%), increased tiredness (57.0%), and dry nose (53.0%). Patients with higher numbers of total and systemic adverse effects experienced worse HrQoL, whereas no associations were found for smoking status or alcohol consumption. The majority (54.8%) of adverse effects were untreated and unreported to health professionals.

Conclusions

Adverse effects are common among patients with LTOT and are associated with worse HrQoL. As the majority of adverse effects had not been discussed or treated, structured assessment and management of risk exposures and adverse effects is warranted.

Perspectives on palliative oxygen for breathlessness: systematic review and meta-synthesis

Oxygen therapy is frequently prescribed for the palliation of breathlessness, despite lack of evidence for its effectiveness in people who are not hypoxaemic. This study aimed to compare and contrast patients', caregivers' and clinicians' experiences of palliative oxygen use for the relief of chronic breathlessness in people with advanced life-limiting illnesses, and how this shapes prescribing.A systematic review and meta-synthesis of qualitative data was conducted. MEDLINE, CINAHL and PsycINFO were searched for peer-reviewed studies in English (2000-April 2019) reporting perspectives on palliative oxygen use for reducing breathlessness in people with advanced illnesses in any healthcare setting. After data extraction, thematic synthesis used line-by-line coding of raw data (quotes) to generate descriptive and analytical themes.Of 457 articles identified, 22 met the inclusion criteria by reporting perspectives of patients (n=337), caregivers (n=91) or clinicians (n=616). Themes common to these perspectives were: 1) benefits and burdens of palliative oxygen use, 2) knowledge and perceptions of palliative oxygen use beyond the guidelines, and 3) longitudinal trajectories of palliative oxygen use.There are differing perceptions regarding the benefits and burdens of using palliative oxygen. Clinicians should be aware that oxygen use may generate differing goals of therapy for patients and caregivers. These perceptions should be taken into consideration when prescribing oxygen for the symptomatic relief of chronic breathlessness in patients who do not quality for long-term oxygen therapy.

[Guideline for Long-Term Oxygen Therapy - S2k-Guideline Published by the German Respiratory Society]

Long-term oxygen therapy is of great importance both for reducing mortality and for improving performance in patients with chronic lung diseases. The prerequisites for Long-term oxygen therapy are adequate diagnostics and clearly defined indication. A causal distinction into chronic hypoxaemic and hypercapnic respiratory failure is reasonable, from which the differential indication for non-invasive ventilation results.The revised guideline covers the diagnostics and indication of chronic lung and heart diseases, the role of oxygen in terminal illness and gives a detailed description of available oxygen devices. The guideline is intended to help avoid undersupply, oversupply and false prescriptions. Furthermore, the chapter "Postacute Oxygen Therapy" discusses the procedure, relevant in everyday life, but not yet clearly defined, for prescribing oxygen therapy for the home at the end of an inpatient stay. Another important point, the correct prescription of mobile oxygen systems, is also presented in the guideline. This document is a revised version of the guideline for longterm oxygen therapy and replaces the version of 2008.

Long-Term Oxygen Therapy and Risk of Fire-Related Events

Introduction

Two large major trials showed that long-term oxygen therapy (LTOT) improved mortality in patients with chronic obstructive pulmonary disease (COPD) and hypoxemia. Although oxygen accelerates combustion and is an obvious fire hazard, LTOT has traditionally been prescribed to veterans who are actively smoking.

Methods

We conducted a retrospective chart review of all veterans with COPD at a single center who were prescribed new LTOT between October 2010 and September 2015. Of the 158 patients who met the study criteria, 152 were male. Bayesian logistic regression was used to model the outcome variable fire-related incident with the predictors smoking status, age, race, depression, posttraumatic stress disorder, and type of oxygen used.

Results

The mean age of the 158 patients with COPD in the study was 71.3 years in nonsmokers and 65.9 years in smokers. The model-estimated odds (SD) of a fire-related incident occurring in a smoker were 31.6 (5.1-372.7) times the odds of a fire-related incident occurring in a nonsmoker.

Conclusions

Patients who smoke and remain on LTOT put themselves at greater risk of having a fire-related incident than do nonsmokers.

Home Oxygen in Chronic Obstructive Pulmonary Disease

Two landmark trials conducted more than 35 years ago provided scientific evidence that, under very specific circumstances, long-term oxygen therapy (LTOT) may prolong life. These two trials enrolled 290 patients with chronic obstructive pulmonary disease and severe daytime hypoxemia documented by direct arterial blood gas measurement. From that time, LTOT became a standard of care, and the indications for oxygen therapy expanded to include nocturnal oxygen therapy for isolated nocturnal oxygen desaturation, ambulatory oxygen to correct exercise-induced desaturation, and short-burst oxygen to relieve dyspnea. In most cases, the rationale for broadening the indications for oxygen therapy is that, if hypoxemia exists, correcting it by increasing the Fi_O2 should help. However, with the exception of LTOT in severely hypoxemic patients with chronic obstructive pulmonary disease, randomized controlled trials of oxygen therapy have failed to demonstrate clinically significant benefits. Also, adherence to LTOT is usually suboptimal. Important areas for future research include improving understanding of the mechanisms of action of supplemental oxygen, the clinical and biochemical predictors of responsiveness to LTOT, the methods for measuring and enhancing adherence to LTOT, and the cost-effectiveness of oxygen therapy. A standardization of terminology to describe the use of supplemental oxygen at home is provided.