Criteria For Long-term Oxygen Therapy Research Articles

Korean physician prescription patterns for home oxygen therapy in chronic obstructive pulmonary disease patients.

Background/AimsHypoxemia in chronic obstructive pulmonary disease (COPD) leads to reduced ability to exercise, decreased quality of life, and, eventually, increased mortality. Home oxygen therapy in patients with severe COPD reduces distress symptoms and mortality rates. However, there have been few studies on physicians’ prescription behavior toward home oxygen therapy. Therefore, we investigated the respiratory specialists’ perspective on home oxygen therapy.MethodsIn this cross-sectional, study, a questionnaire was completed by 30 pulmonary specialists who worked in tertiary hospitals and prescribed home oxygen therapy. The questionnaire consisted of 28 items, including 15 items on oxygen prescription for outpatients, four for inpatients, and nine on service improvement.ResultsAll physicians were prescribing less than 2 L/min of oxygen for either 24 (n = 10, 33.3%) or 15 hours (n = 9, 30.3%). All (n = 30) used pulse oximetry, 26 (86.7%) analyzed arterial blood gas. Thirteen physicians had imposed restrictions and recommended oxygen use only during exercise or sleep. Sixteen (53.3%) physicians were educating their patients about home oxygen therapy. Furthermore, physicians prescribed home oxygen to patients that did not fit the typical criteria for long-term oxygen therapy, with 30 prescribing it for acute relief and 17 for patients with borderline hypoxemia.ConclusionsThis study identified the prescription pattern of home oxygen therapy in Korea. Respiratory physicians prescribe home oxygen therapy to hypoxemic COPD patients for at least 15 hours/day, and at a rate of less than 2 L/min. More research is needed to provide evidence for establishing policies on oxygen therapy in COPD patients.

Randomized Trial of Nocturnal Oxygen in Chronic Obstructive Pulmonary Disease

BackgroundLong-term oxygen therapy improves survival in patients with chronic obstructive pulmonary disease (COPD) and chronic severe daytime hypoxemia. However, the efficacy of oxygen therapy for the management of isolated nocturnal hypoxemia is uncertain.MethodsWe designed this double-blind, placebo-controlled, randomized trial to determine, in patients with COPD who have nocturnal arterial oxygen desaturation without qualifying for long-term oxygen therapy, whether nocturnal oxygen provided for a period of 3 to 4 years would decrease mortality or the worsening of disease such that patients meet current specifications for long-term oxygen therapy. Patients with an oxygen saturation of less than 90% for at least 30% of the recording time on nocturnal oximetry were assigned, in a 1:1 ratio, to receive either nocturnal oxygen or ambient air from a sham concentrator (placebo). The primary outcome was a composite of death from any cause or a requirement for long-term oxygen therapy as defined by the Nocturnal Oxygen Therapy Trial (NOTT) criteria in the intention-to-treat population.ResultsRecruitment was stopped prematurely because of recruitment and retention difficulties after 243 patients, of a projected 600, had undergone randomization at 28 centers. At 3 years of follow-up, 39.0% of the patients assigned to nocturnal oxygen (48 of 123) and 42.0% of those assigned to placebo (50 of 119) met the NOTT-defined criteria for long-term oxygen therapy or had died (difference, −3.0 percentage points; 95% confidence interval, −15.1 to 9.1).ConclusionsOur underpowered trial provides no indication that nocturnal oxygen has a positive or negative effect on survival or progression to long-term oxygen therapy in patients with COPD. (Funded by the Canadian Institutes of Health Research; INOX ClinicalTrials.gov number, NCT01044628.)

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

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. 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. 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%. 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.

Oxygen for breathlessness in patients with chronic obstructive pulmonary disease who do not qualify for home oxygen therapy.

Breathlessness is a cardinal symptom of chronic obstructive pulmonary disease (COPD). Long-term oxygen therapy (LTOT) is given to improve survival time in people with COPD and severe chronic hypoxaemia at rest. The efficacy of oxygen therapy for breathlessness and health-related quality of life (HRQOL) in people with COPD and mild or no hypoxaemia who do not meet the criteria for LTOT has not been established. To determine the efficacy of oxygen versus air in mildly hypoxaemic or non-hypoxaemic patients with COPD in terms of (1) breathlessness; (2) HRQOL; (3) patient preference whether to continue therapy; and (4) oxygen-related adverse events. We searched the Cochrane Airways Group Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase, to 12 July 2016, for randomised controlled trials (RCTs). We handsearched the reference lists of included articles. We included RCTs of the effects of non-invasive oxygen versus air on breathlessness, HRQOL or patient preference to continue therapy among people with COPD and mild or no hypoxaemia (partial pressure of oxygen (PaO2) > 7.3 kPa) who were not already receiving LTOT. Two review authors independently assessed articles for inclusion in the review. Two review authors independently collected and analysed data. We assessed risk of bias by using the Cochrane 'Risk of bias tool'. We pooled effects recorded on different scales as standardised mean differences (SMDs) with 95% confidence intervals (CIs) using random-effects models. Lower SMDs indicated decreased breathlessness and reduced HRQOL. We performed subanalyses and sensitivity analyses and assessed the quality of evidence according to the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Compared with the previous review, which was published in 2011, we included 14 additional studies (493 participants), excluded one study and included data for meta-analysis of HRQOL. In total, we included in this review 44 studies including 1195 participants, and we included 33 of these (901 participants)in the meta-analysis.We found that breathlessness during exercise or daily activities was reduced by oxygen compared with air (32 studies; 865 participants; SMD -0.34, 95% CI -0.48 to -0.21; I2 = 37%; low-quality evidence). This translates to a decrease in breathlessness of about 0.7 points on a 0 to 10 numerical rating scale. In contrast, we found no effect of short-burst oxygen given before exercise (four studies; 90 participants; SMD 0.01, 95% CI -0.26 to 0.28; I2 = 0%; low-quality evidence). Oxygen reduced breathlessness measured during exercise tests (25 studies; 442 participants; SMD -0.34, 95% CI -0.46 to -0.22; I2 = 29%; moderate-quality evidence), whereas evidence of an effect on breathlessness measured in daily life was limited (two studies; 274 participants; SMD -0.13, 95% CI, -0.37 to 0.11; I2 = 0%; low-quality evidence).Oxygen did not clearly affect HRQOL (five studies; 267 participants; SMD 0.10, 95% CI -0.06 to 0.26; I2 = 0%; low-quality evidence). Patient preference and adverse events could not be analysed owing to insufficient data. We are moderately confident that oxygen can relieve breathlessness when given during exercise to mildly hypoxaemic and non-hypoxaemic people with chronic obstructive pulmonary disease who would not otherwise qualify for home oxygen therapy. Most evidence pertains to acute effects during exercise tests, and no evidence indicates that oxygen decreases breathlessness in the daily life setting. Findings show that oxygen does not affect health-related quality of life.

Does home oxygen therapy (HOT) in addition to standard care reduce disease severity and improve symptoms in people with chronic heart failure? A randomised trial of home oxygen therapy for patients with chronic heart failure

Home oxygen therapy (HOT) is commonly used for patients with severe chronic heart failure (CHF) who have intractable breathlessness. There is no trial evidence to support its use. To detect whether or not there was a quality-of-life benefit from HOT given as long-term oxygen therapy (LTOT) for at least 15 hours per day in the home, including overnight hours, compared with best medical therapy (BMT) in patients with severely symptomatic CHF. A pragmatic, two-arm, randomised controlled trial recruiting patients with severe CHF. It included a linked qualitative substudy to assess the views of patients using home oxygen, and a free-standing substudy to assess the haemodynamic effects of acute oxygen administration. Heart failure outpatient clinics in hospital or the community, in a range of urban and rural settings. Patients had to have heart failure from any aetiology, New York Heart Association (NYHA) class III/IV symptoms, at least moderate left ventricular systolic dysfunction, and be receiving maximally tolerated medical management. Patients were excluded if they had had a cardiac resynchronisation therapy device implanted within the past 3 months, chronic obstructive pulmonary disease fulfilling the criteria for LTOT or malignant disease that would impair survival or were using a device or medication that would impede their ability to use LTOT. Patients received BMT and were randomised (unblinded) to open-label LTOT, prescribed for 15 hours per day including overnight hours, or no oxygen therapy. The primary end point was quality of life as measured by the Minnesota Living with Heart Failure (MLwHF) questionnaire score at 6 months. Secondary outcomes included assessing the effect of LTOT on patient symptoms and disease severity, and assessing its acceptability to patients and carers. Between April 2012 and February 2014, 114 patients were randomised to receive either LTOT or BMT. The mean age was 72.3 years [standard deviation (SD) 11.3 years] and 70% were male. Ischaemic heart disease was the cause of heart failure in 84%; 95% were in NYHA class III; the mean left ventricular ejection fraction was 27.8%; and the median N-terminal pro-B-type natriuretic hormone was 2203 ng/l. The primary analysis used a covariance pattern mixed model which included patients only if they provided data for all baseline covariates adjusted for in the model and outcome data for at least one post-randomisation time point (n = 102: intervention, n = 51; control, n = 51). There was no difference in the MLwHF questionnaire score at 6 months between the two arms [at baseline the mean score was 54.0 (SD 18.4) for LTOT and 54.0 (SD 17.9) for BMT; at 6 months the mean score was 48.1 (SD 18.5) for LTOT and 49.0 (SD 20.2) for BMT; adjusted mean difference -0.10, 95% confidence interval (CI) -6.88 to 6.69; p = 0.98]. At 3 months, the adjusted mean MLwHF questionnaire score was lower in the LTOT group (-5.47, 95% CI -10.54 to -0.41; p = 0.03) and breathlessness scores improved, although the effect did not persist to 6 months. There was no effect of LTOT on any secondary measure. There was a greater number of deaths in the BMT arm (n = 12 vs. n = 6). Adherence was poor, with only 11% of patients reporting using the oxygen as prescribed. Although the study was significantly underpowered, HOT prescribed for 15 hours per day and subsequently used for a mean of 5.4 hours per day has no impact on quality of life as measured by the MLwHF questionnaire score at 6 months. Suggestions for future research include (1) a trial of patients with severe heart failure randomised to have emergency oxygen supply in the house, supplied by cylinders rather than an oxygen concentrator, powered to detect a reduction in admissions to hospital, and (2) a study of bed-bound patients with heart failure who are in the last few weeks of life, powered to detect changes in symptom severity. Current Controlled Trials ISRCTN60260702. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 75. See the NIHR Journals Library website for further project information.

Eligibility for home oxygen programs and funding across Canada.

In Canada, although medical insurance is generally universal, significant differences exist in the provision of home oxygen therapy across the country. To systematically compare the terms of reference for home oxygen across Canada, with a focus on the clinical inclusion criteria to the programs. The authors searched the terms of reference of the 10 Canadian provinces and three territories, focusing on general eligibility criteria for home oxygen (including blood gas criteria, and eligibility criteria for ambulatory and nocturnal oxygen), and compared the eligibility criteria to the widely accepted criteria of the Nocturnal Oxygen Therapy Trial (NOTT) trial, the clinical recommendations of the Canadian Thoracic Society and the results of Cochrane reviews. The terms of reference for nine provinces were retrieved. All jurisdictions have similar criteria for long-term oxygen therapy, with slight differences in the thresholds of prescription and the clinical criteria defining 'pulmonary hypertension' or 'cor pulmonale'. The use of oxyhemoglobin saturation as a criterion for funding is inconsistent. All nine provinces fund nocturnal oxygen, all with different clinical criteria. Funding for portable oxygen widely varies across provinces, whether the ambulatory equipment is offered to patients on long-term oxygen therapy or to those who have isolated exercise-induced desaturation. The terms of reimbursement are very heterogeneous. Heterogeneity exists in the criteria for eligibility to home oxygen programs and funding across Canada. Terms of prescription and reimbursement of oxygen are not necessarily supported by available evidence from the current literature in several Canadian jurisdictions.

Ambulatory oxygen for people with chronic obstructive pulmonary disease who are not hypoxaemic at rest.

People with chronic obstructive pulmonary disease (COPD) often become transiently hypoxaemic (low oxygen levels in blood) on exercise, necessitating oxygen therapy to improve breathlessness and exercise capacity and to reduce disability. Ambulatory oxygen therapy refers to provision of oxygen therapy during exercise and activities of daily living. Ambulatory oxygen therapy is often used by patients on long-term oxygen therapy (LTOT) during exercise or by non-LTOT users with or without resting hypoxaemia when they show evidence of exercise de-saturation and demonstrate improvement in exercise capacity with supplemental oxygen. To determine the longer-term efficacy of ambulatory oxygen therapy only in patients with COPD who do not meet the criteria for LTOT, with respect to improvement in exercise capacity, mortality, quality of life and other relevant measures of improvement. The Cochrane Airways Group Specialised Register, including MEDLINE, EMBASE and CINAHL, was searched. Online clinical trial registers, including Controlled Clinical Trials (www.controlled-trials.com), government registries (clinicaltrials.gov) and World Health Organization (WHO) registries (www.who.int/trialsearch), were screened for ongoing and recently completed studies. Bibliographies of included studies were searched for additional trials that may meet the inclusion criteria and were not retrieved by the above search strategy. Authors of identified trials were contacted to provide other published and unpublished studies. Searches were current as of November 2012. Randomised controlled trials (RCTs) that compare ambulatory oxygen therapy provided through portable oxygen cylinders/battery-powered devices or liquid oxygen canisters versus placebo air cylinders, usual medical care or co-intervention in study participants with COPD who did not meet criteria for LTOT. We used standard methods as expected by The Cochrane Collaboration. Four studies met the inclusion criteria (331 participants), with two studies producing a statistically and clinically significant benefit in favour of the intervention for dyspnoea post exercise.The quality of life domain for all four included studies produced a statistically significant benefit for the subcategories of dyspnoea and fatigue, in favour of the oxygen group (dyspnoea mean difference (MD) 0.28, 95% confidence interval (CI) 0.10 to 0.45; P value 0.002; fatigue MD 0.17, 95% CI 0.04 to 0.31; P value 0.009). No evidence ofany effect was reported for survival, and limited benefits were observed for exercise capacity (as measured by step test and distance walk test), with one study showing a statistically significant improvement in the number of steps taken in the oxygen group for group N-of-1 studies only. No other statistically significant benefits were observed for exercise capacity among the other trials or individual N-of-1 studies. In patients with COPD with moderate hypoxia, current evidence on ambulatory oxygen therapy reveals improvements in dyspnoea post exercise and in the dyspnoea and fatigue domain of quality of life. However, evidence for the clinical utility and effectiveness of ambulatory oxygen in improving mortality and exercise capacity was not evident in this review. Methodologically rigorous RCTs with sufficient power to detect a difference are required to investigate the role of ambulatory oxygen in the management of COPD.

P44 How Long is short term Oxygen Therapy? Home Oxygen Prescriptions Post Hospitalisation

Introduction Long-term oxygen therapy (LTOT) has been shown to improve survival in some patients with chronic obstructive pulmonary disease (COPD); generalisation to other groups of hypoxic patients is less clear. The British Thoracic Society recommend LTOT should be prescribed to hypoxic patients after appropriate assessment during a period of clinical stability.¹ In practise LTOT is frequently prescribed following hospitalisation. This form of oxygen therapy has been termed short-term oxygen therapy (STOT). We sought to audit our practise of prescribing home oxygen therapy to hypoxic patients following hospital admission with an exacerbation of a respiratory disorder. Method We performed a retrospective case note audit of 30 patients [13 male] commenced on home oxygen therapy at discharge over a 6 month period recording patient demographics, smoking status, underlying diagnosis, compliance with BTS oxygen prescribing guidelines and the outcome of follow-up. Results The mean age was 71 years (48–91yrs); 17% current smokers, 73% ex-smokers. COPD was the most common diagnosis in 80% (24/30); the mean FEV1 1.1L (52% predicted). No definitive diagnosis was documented in 10% (3/30) with 10% diagnosed with sarcoidosis, idiopathic pulmonary fibrosis or lung cancer. 64% (19/30) of patients met BTS LTOT criteria, (80% (19/24) with COPD), 33% (10/30) did not and 3% (1/30) were prescribed palliative oxygen. 93% of patients (27/29) were followed up at 3 months. The mean oxygen flow rate required was 1.4L/min; oxygen flow rate was altered in 63%. The overwhelming majority of our patients, 90% (26/29), continued with LTOT after reassessment at 3 months and 79% (23/29) at 6 months. Conclusion Our audit shows that the majority of patients commenced on oxygen therapy post hospitalisation met the criteria for LTOT and continued to require oxygen at 3 and 6 months; this is a higher figure than quoted in the majority of the literature. This suggests our patients are presenting late with underlying chronic lung disease; we need to strive to identify these patients earlier. There is still a lack of evidence-based guidelines for STOT and further research in this area is needed. References BTS Home Oxygen Service in England and Wales. January 2006.

P106 Reduction of inappropriate oxygen prescriptions by a home oxygen service

Introduction and ObjectivesHome Oxygen in England costs around £110 million yet it is estimated that 30% of patients derive no clinical benefit (DH, 2010).1 In addition oxygen can be harmful...

Predicting Nocturnal Hypoventilation in Hypercapnic Chronic Obstructive Pulmonary Disease Patients Undergoing Long-Term Oxygen Therapy

Background: Chronic obstructive pulmonary disease (COPD) patients are very sensitive to changes in pulmonary mechanics and central ventilation control during sleep and may develop significant gas exchange alterations with increased hypoxemia and hypercapnia. Oxygen therapy improves nocturnal desaturation but can worsen hypoventilation. Objectives: To analyze the prevalence of nocturnal hypoventilation (NHV) in hypercapnic COPD patients and to determine predictive factors for this phenomenon. Methods: This was a prospective multicenter study which enrolled 80 clinically stable COPD patients with hypercapnic respiratory failure who fulfilled the conventional criteria for long-term oxygen therapy (LTOT). All patients had undergone pulmonary function testing, blood gas analysis, and respiratory polygraphy. Arterial blood gas samples were obtained while patients were awake and during sleep. NHV was considered when an increase in PaCO₂ >10 mm Hg was observed in any nocturnal arterial blood gas sample as compared to the awake levels. Results: Seventeen patients (21%) developed NHV. NHV was associated with the values of BMI, hemoglobin, hematocrits, DLCO, and PaO₂ reached after oxygen administration. In the logistic regression analysis BMI (OR 1.26, 95% CI 1.068–1.481; p = 0.006) and the diurnal increase of PaO₂ after O₂ (OR 0.89, 95% CI 0.807–0.972; p = 0.010) were the variables that best discriminated with a sensitivity of 82% and a specificity of 78%. Conclusions: NHV is a relatively common finding in stable hypercapnic COPD patients undergoing LTOT and it is related to a higher BMI and lower PaO₂ after oxygen administration.

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.

Oxygen therapy during exercise training in chronic obstructive pulmonary disease

Exercise training within the context of pulmonary rehabilitation improves outcomes of exercise capacity, dyspnea and health-related quality of life in individuals with chronic obstructive pulmonary disease (COPD). Supplemental oxygen in comparison to placebo increases exercise capacity in patients performing single-assessment exercise tests. The addition of supplemental oxygen during exercise training may enable individuals with COPD to tolerate higher levels of activity with less exertional symptoms, ultimately improving quality of life. To determine how supplemental oxygen in comparison to control (compressed air or room air) during the exercise-training component of a pulmonary rehabilitation program affects exercise capacity, dyspnea and health-related quality of life in individuals with COPD. All records in the Cochrane Airways Group Specialized Register of trials coded as 'COPD' were searched using the following terms: (oxygen* or O2*) AND (exercis* or train* or rehabilitat* or fitness* or physical* or activ* or endur* or exert* or walk* or cycle*). Searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, EMBASE and CINAHL databases identified studies. The last search was carried out in June 2006. Only randomized controlled trials (RCTs) comparing oxygen-supplemented exercise training to non-supplemented exercise training (control group) were considered for inclusion. Participants were 18 years or older, diagnosed with COPD and did not meet criteria for long-term oxygen therapy. No studies with mixed populations (pulmonary fibrosis, cystic fibrosis, etc) were included. Exercise training was greater than or equal to three weeks in duration and included a minimum of two sessions a week. Two review authors independently selected trials for inclusion in the review and extracted data. Weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated using a random-effects model. Missing data were requested from authors of primary studies. Five RCTs met the inclusion criteria. The maximum number of studies compared in the meta-analysis was three (31 on oxygen versus 32 control participants), because all included studies did not measure the same outcomes. When two studies were pooled, statistically significant improvements of oxygen-supplemented exercise training were found in constant power exercise time, WMD 2.68 minutes (95% CI 0.07 to 5.28 minutes). Supplemental oxygen increased the average exercise time from 6 to 14 minutes; the control intervention increased average exercise time from 6 to 12 minutes. Constant power exercise end-of-test Borg score (on a scale from 1 to 10) also showed statistically significant improvements with oxygen-supplemented exercise training, WMD -1.22 units (95% CI -2.39 to -0.06). One study showed a significant improvement in the change of Borg score after the shuttle walk test, by -1.46 units (95% CI -2.72 to -0.19). There were no significant differences in maximal exercise outcomes, functional exercise outcomes (six-minute walk test), shuttle walk distance, health-related quality of life or oxygenation status. According to the GRADE system most outcomes were rated as low quality because they were limited by study quality. This review provides little support for oxygen supplementation during exercise training for individuals with COPD, but the evidence is very limited. Studies with larger number of participants and strong design are required to permit strong conclusions, especially for functional outcomes such as symptom alleviation, health-related quality of life and ambulation.

Inhaled corticosteroids and survival in COPD patients receiving long-term home oxygen therapy

Several observational studies suggest that therapy with inhaled corticosteroids (ICS) is associated with reduced mortality in patients with chronic obstructive pulmonary disease (COPD). However, none of these has reported survival data in COPD patients with respiratory insufficiency who require domiciliary oxygen therapy. The present study was conducted to examine the association between ICS and all-cause mortality in patients with severe COPD and chronic hypoxemia. From a tertiary referral clinic, we identified 145 consecutive COPD patients who met the criteria for long-term oxygen therapy between 1996 and 2002. We compared the hazard ratio (HR) for all-cause mortality over 1 year between patients who were (n=55) and were not treated with ICS (n=90). In a crude analysis, the use of ICS was associated with a HR of 0.38 (95% confidence interval (CI)=0.18-0.79). After adjustments for age, sex, use of oral steroids, and beta2-agonists, PaO2 and PaCO2, the HR was 0.46 (95% CI=0.21-0.98). Our findings indicate that ICS may reduce all-cause mortality in patients with severe COPD and chronic hypoxemia, who require long-term domiciliary oxygen therapy. These data suggest that ICS may play an important role in improving clinical outcomes in patients with advanced COPD.

The impact of the Danish Oxygen Register on adherence to guidelines for long-term oxygen therapy in COPD patients

To evaluate the impact of The Danish Oxygen Register on COPD patients' treatment modalities, survival, and adherence to guidelines for long-term oxygen therapy (LTOT). The Danish Oxygen Register. 8487 COPD patients who received LTOT in the study period from November 1, 1994, to December 31, 2000. Follow-up, smoking status, correct prescription of LTOT (15-24h/day), and survival. During the study period an increasing number of patients were prescribed LTOT in connection with discharge after hospitalisation for an exacerbation (1995 vs. 2000: 74.4% vs. 82.2%, P<0.001), were prescribed oxygen 15-24h/day (66.2% vs. 85.5%, P<0.001), had delivered oxygen concentrator or liquid oxygen (77.8% vs. 96.9%, P<0.001), and had mobile oxygen (29.9% vs. 42.8%, P<0.001). Only 65.8% of the patients were followed-up in an outpatient clinic with the possibility of re-evaluation of the criteria for LTOT and adjustment for oxygen flow, with no change during the study period (P=0.43). In a representative subsample, 77.1% had smoking habits or measurement of CO-level registered in 1995 compared to 79.6% in year 2000 (P=0.65), and 25.1% vs. 21.2% (P=0.34) were considered current smokers. The median survival increased from 1.07 to 1.40 years (P=0.032). Adherence to guidelines for LTOT has improved concerning administration of oxygen, but has remained poor concerning follow-up of the patients and smoking cessation. Survival of COPD patients on LTOT has improved during the observation period.

Implementation of an Oxygen Therapy Clinic to Manage Users of Long-term Oxygen Therapy

To evaluate the initial benefits of establishing an oxygen therapy clinic (OTC) to manage users of long-term oxygen therapy (LTOT). Cross-sectional observational study. Military-affiliated, tertiary care hospital. Current users of LTOT at our institution and patients with new oxygen prescriptions between June 2000 and May 2001. The OTC evaluation consisted of a focused medical interview and physical examination by a respiratory therapist. Demographic data, indications for supplemental oxygen, oxygen-related diagnoses, cardiopulmonary review of systems, pertinent physical examination findings, pulmonary function testing, and oximetry data were recorded. Patients prescribed oxygen during hospitalization were followed up for recertification within 90 days based on the recommendations of the Fifth Oxygen Consensus Conference. Also, patients with existing oxygen prescriptions and new oxygen prescriptions during the study period were evaluated in the OTC. Data are provided for the initial evaluation in this clinic. A total of 283 patients were evaluated in the OTC during the study period. Ninety-seven patients with a new oxygen prescription during hospitalization were evaluated, with a mean +/- SE time from discharge to evaluation of 2.6 +/- 0.4 months. At follow-up, 50.5% of these patients no longer met Medicare guidelines for LTOT. A significant change in oxygen prescription was required in 27.9% of these patients. A total of 95 outpatients with existing oxygen prescriptions were contacted for recertification in the OTC. Of these patients, 31.6% no longer met Medicare criteria for LTOT and 26% required a significant change to their oxygen prescription. Oxygen therapy was discontinued in 22% of the 91 patients who were referred from other outpatient clinics, and the oxygen prescription was changed in another 29.7%. Results of this initial evaluation suggest that the institution of a respiratory therapist-managed OTC to manage home oxygen patients can significantly decrease inappropriate supplemental oxygen use, which can result in significant cost savings while providing improved health-care delivery. Further evaluation is necessary to identify the long-term benefits and cost savings in this population.

An evaluation of short-term oxygen therapy: the prescription of oxygen to patients with chronic lung disease hypoxic at discharge from hospital

The provision of domiciliary oxygen to patients hypoxic at hospital discharge has been termed short-term oxygen therapy (STOT). This practice appears widespread, although there is a paucity of literature and no evidence-based guidelines. We undertook this audit to examine the prescription of STOT and determine the proportion fulfilling for long-term oxygen therapy (LTOT) 2 months post-discharge. STOT was defined prospectively: resting P aO 2≤7·3 kPa (55 mmHg) or P aO 2between 7·3 and 8·0 kPa (60 mmHg) with any of the following: clinical evidence of cor pulmonale (pedal oedema or jugular venous distension), ECG evidence of pulmonale, echocardiogram evidence of pulmonary hypertension, haematocrit>0·55 (adapted directly from LTOT criteria). Patients were evaluated for LTOT 2 months post-discharge when clinically stable on optimal medical management. All referrals to the Auckland Regional Oxygen Service between July 1998 and 1999 were systematically reviewed. The majority 289/405 (71%) of new referrals were for the prescription of STOT/LTOT in patients with chronic lung disease: 160/289 (55%) derived from hospitalized patients with the majority 130 (81%) fulfilling criteria for STOT, median age 73, range 24–96 years. Mean hospital stay was 10·2 days. Two months after discharge 22/127 (17%) of STOT patients had died, comparable with 4/22 (18%) not fulfilling criteria for STOT. A total of 123 patients were assessed for LTOT at 2 months; 76 (62%) fulfilled criteria for LTOT. The prescription of oxygen at hospital discharge represented a considerable proportion of our referral load. There was a high mortality in the 2-month follow-up period. A significant proportion of STOT patients did not subsequently fulfill criteria for LTOT. Further prospective studies are required in order to develop evidence-based guidelines.

Improvement in patient compliance with long-term oxygen therapy following formal assessment with training

In the Department of Respiratory Medicine, North Staffordshire Hospital, patients fulfilling the Department of Health criteria for long-term oxygen therapy (LTOT) attend a practical teaching session on the use of their oxygen concentrator before commencing therapy. In the present study, we have audited the prescribing of LTOT in all patients in three health districts in the North West Midlands reviewed between June 1992 and July 1994. They were split into two groups. The first had the assessment and training programme in the department. Patients in the control group had been prescribed LTOT from outside the department without any formal training. In both groups of patients information was collated 6 months after starting LTOT by means of a questionnaire assessing patients', understanding of both their need for oxygen and their disease process, the dangers of oxygen therapy and present smoking habit. Objective information about the usage of each concentrator was obtained from engineer reports. Thirty-six patients (eight from the trained group and 28 controls) died before evaluation at 6 months. Forty-five patients (29 male, mean age 71 years) received training and 41 control patients (24 male, mean age 72 years) were evaluated. Thirty-seven (82%) patients who had received formal training were using their concentrator for greater than 15 h compared with only 18 (44%) of the controls ( P=0·0002). Forty-two (93%) patients who had received training understood why they were using LTOT compared with only 17 (41%) in the control group ( P=0·00001). Although both groups had a similar understanding of the dangers of smoking while on oxygen therapy, six (15%) of the control group were smoking as compared to only one (2%) of the trained group ( P=0·038). One of the control patients had received significant facial burns as a direct result of smoking while on oxygen. Further efforts are required to ensure that all patients prescribed LTOT should have a formal respiratory assessment as well as training to improve compliance and to obtain maximal benefits from such therapy.

The value of forced expiratory volume in 1 s in screening subjects with stable COPD for PaO 2 < 7·3 kPa qualifying for long-term oxygen therapy

Guidelines on the management of chronic obstructive pulmonary disease (COPD) issued by the European Respiratory Society (ERS), British Thoracic Society (BTS), American Thoracic Society (ATS), and Department of Health for England and Wales (DoH) suggest differing values of forced expiratory volume in 1 s (FEV 1) below which arterial blood gas analysis should be performed to determine the presence of severe hypoxaemia and possible long-term oxygen therapy (LTOT) requirement. This study aimed to determine the value of FEV 1 at these different levels in screening for LTOT requirement defined as PaO 2 < 7·3 kPa in subjects with stable COPD. Comparative measures were taken against other lung function tests of volume and diffusing capacity. A retrospective analysis of paired lung function and arterial oxygen measurements in 491 subjects was made. The positive and negative predictive values, sensitivity and specificity of FEV 1 < 70% predicted (ERS), FEV 1 < 50% predicted (ATS), FEV 1 < 40% predicted (BTS) and FEV 1 < 1·51 (DoH) were determined for fulfilling LTOT criteria ( PaO 2 < 7·3 kPa). The correlation between lung function variables and PaO 2 was established. Logistic regression analysis was used to classify subjects with PaO 2 < 7·3 kPa and PaO 2 ⩾ 7·3 kPa. Using FEV 1 to screen for LTOT requirement produced a high negative predictive value at all four suggested limits (FEV 1 < 70% 100%, FEV 1 < 50% 96%, FEV 1 < 40% 95%, FEV 1 < 1·51 97%). However, the positive predictive values were low (FEV 1 < 70% 13%, FEV 1 < 50% 16%, FEV 1 < 40% 19%, FEV 1 < 1·51 15%) as were sensitivities. No single lung function variable was a strong determinant of PaO 2. FEV 1 % pred ( r = 0·40), FVC % pred ( r = 0·34) and TLCO % pred ( r = 0·27) had the strongest relationships. Logistic regression also placed FEV 1 % pred and TLCO % pred as the best predictors of PaO 2 < 7·3 kPa. We conclude no lung function variable correlates well with PaO 2 in subjects with stable COPD. The best predictor of PaO 2 < 7·3 kPa was FEV 1 % pred. Whilst a low FEV 1 is a poor predictor of LTOT requirement in an individual, PaO 2 < 7·3 kPa is only found in subjects with a low FEV 1. A high FEV 1 may be used to exclude subjects from further investigation for LTOT and prevent unnecessary arterial sampling.