Which patients with moderate hypoxemia benefit from long-term oxygen therapy? Ways forward

Magnus Ekström,1 Thomas Ringbaek2 1Department of Respiratory Medicine and Allergology, Skåne University Hospital, Lund University, Lund, Sweden; 2Respiratory Department, Hvidovre Hospital, Copenhagen, Denmark Abstract: Long-term oxygen therapy (LTOT) improves prognosis in patients with COPD and chronic severe hypoxemia. The efficacy in moderate hypoxemia (tension of arterial oxygen; on air, 7.4−8.0 kPa) was questioned by a recent large trial. We reviewed the evidence to date (five randomized trials; 1,191 participants, all with COPD). Based on the current evidence, the survival time may be improved in patients with moderate hypoxemia with secondary polycythemia or right-sided heart failure, but not in the absence of these signs. Clinically, LTOT is not indicated in moderate hypoxemia except in the few patients with polycythemia or signs of right-sided heart failure, which may reflect more chronic and severe hypoxemia. Keywords: survival, oxygen therapy, hypoxemia, COP

Tablet computers to support outpatient pulmonary rehabilitation in patients with COPD

BACKGROUND: A minicomputer (tablet) with instructions and a training diary has the potential of facilitating adherence to pulmonary rehabilitation (PR). OBJECTIVE: To evaluate the effect of adding a tablet to a classic outpatient PR programme for COPD patients. METHODS: A total of 115 patients participated in a 7- to 10-week outpatient PR programme in groups of 10–12 individuals. Half of the groups were assigned to PR plus a tablet (tablet group) and the other groups were assigned to PR only (controls). Primary effect parameters were endurance shuttle walk time (ESWT) and disease-specific health status (COPD Assessment Test=CAT). RESULTS: The change in ESWT was significantly better in the control group (mean 167 sec) compared with the tablet group (mean 51 sec) (p<0.01), whereas the change in CAT score did not differ significantly between the two groups (−0.6 vs. −2.3) (p=0.17). CONCLUSIONS: Compared with usual PR, no significant improvements were seen in the group equipped with the tablet after 7–10 weeks of rehabilitation. Future studies should focus on long-term effects

EuroQoL in assessment of the effect of pulmonary rehabilitation COPD patients

SummaryBackgroundThe effect of pulmonary rehabilitation on EuroQol in COPD patients has not been investigated previously.Methods/materialsTwo hundred and twenty nine consecutive COPD patients who had completed a 7-week pulmonary rehabilitation programme were assessed with EuroQol five-dimension questionnaire (EQ-5D), endurance shuttle walk test (ESWT), and the St George's Respiratory Questionnaire (SGRQ) before and after the programme, and at the 3-month follow-up visit.ResultsTwo hundred and two (88.4%) patients had FEV1<50% predicted and all but four (1.7%) had dyspnoea score at least 3 on MRC scale. At completion of the programme, statistical significant improvements were seen for ESWT 157.3s; p<0.001, EQ-5D utility score −0.019; p=0.03, EQ-5D VAS −2.1; p=0.056, SGRQ total score −2.8units; p<0.001. The effects of rehabilitation on ESWT and SGRQ were maintained at 3-month follow-up (158.9s and −2.9units), while the effect on EQ-5 utility decreased (0.013; p=0.18). At baseline, there was a maximum score (“ceiling effect”) for EQ-5D utility and EQ VAS in 29 (12.7%) and five (2.2%) of the patients, respectively. After rehabilitation these number increased to 41 (17.9%) and seven (3.1%).ConclusionsIn COPD patients receiving rehabilitation, responsiveness of EQ-5D utility was poor. One explanation might be a “ceiling effect” of this instrument

Effect of endurance versus resistance training on quadriceps muscle dysfunction in COPD:a pilot study

INTRODUCTION: Exercise is an important countermeasure to limb muscle dysfunction in COPD. The two major training modalities in COPD rehabilitation, endurance training (ET) and resistance training (RT), may both be efficient in improving muscle strength, exercise capacity, and health-related quality of life, but the effects on quadriceps muscle characteristics have not been thoroughly described. METHODS: Thirty COPD patients (forced expiratory volume in 1 second: 56% of predicted, standard deviation [SD] 14) were randomized to 8 weeks of ET or RT. Vastus lateralis muscle biopsies were obtained before and after the training intervention to assess muscle morphology and metabolic and angiogenic factors. Symptom burden, exercise capacity (6-minute walking and cycle ergometer tests), and vascular function were also assessed. RESULTS: Both training modalities improved symptom burden and exercise capacity with no difference between the two groups. The mean (SD) proportion of glycolytic type IIa muscle fibers was reduced after ET (from 48% [SD 11] to 42% [SD 10], P<0.05), whereas there was no significant change in muscle fiber distribution with RT. There was no effect of either training modality on muscle capillarization, angiogenic factors, or vascular function. After ET the muscle protein content of phosphofructokinase was reduced (P<0.05) and the citrate synthase content tended increase (P=0.08) but no change was observed after RT. CONCLUSION: Although both ET and RT improve symptoms and exercise capacity, ET induces a more oxidative quadriceps muscle phenotype, counteracting muscle dysfunction in COPD

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

Background: 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.Objectives: To detect whether or not there was a quality-of-life benefit from HOT given as long-termoxygen therapy (LTOT) for at least 15 hours per day in the home, including overnight hours, comparedwith best medical therapy (BMT) in patients with severely symptomatic CHF.Design: A pragmatic, two-arm, randomised controlled trial recruiting patients with severe CHF. It includeda linked qualitative substudy to assess the views of patients using home oxygen, and a free-standingsubstudy to assess the haemodynamic effects of acute oxygen administration.Setting: Heart failure outpatient clinics in hospital or the community, in a range of urban andrural settings.Participants: 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 maximallytolerated medical management. Patients were excluded if they had had a cardiac resynchronisation therapydevice implanted within the past 3 months, chronic obstructive pulmonary disease fulfilling the criteria forLTOT or malignant disease that would impair survival or were using a device or medication that wouldimpede their ability to use LTOT.Interventions: Patients received BMT and were randomised (unblinded) to open-label LTOT, prescribed for15 hours per day including overnight hours, or no oxygen therapy.Main outcome measures: The primary end point was quality of life as measured by the Minnesota Livingwith Heart Failure (MLwHF) questionnaire score at 6 months. Secondary outcomes included assessing theeffect of LTOT on patient symptoms and disease severity, and assessing its acceptability to patientsand carers.Results: Between April 2012 and February 2014, 114 patients were randomised to receive either LTOT orBMT. The mean age was 72.3 years [standard deviation (SD) 11.3 years] and 70% were male. Ischaemicheart disease was the cause of heart failure in 84%; 95% were in NYHA class III; the mean left ventricularejection 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 datafor all baseline covariates adjusted for in the model and outcome data for at least one post-randomisationtime point (n = 102: intervention, n = 51; control, n = 51). There was no difference in the MLwHF questionnairescore at 6 months between the two arms [at baseline the mean score was 54.0 (SD 18.4) for LTOT and54.0 (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) forBMT; 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 BMTarm (n = 12 vs. n = 6). Adherence was poor, with only 11% of patients reporting using the oxygenas prescribed.Conclusions: Although the study was significantly underpowered, HOT prescribed for 15 hours per dayand subsequently used for a mean of 5.4 hours per day has no impact on quality of life as measured bythe MLwHF questionnaire score at 6 months. Suggestions for future research include (1) a trial of patientswith severe heart failure randomised to have emergency oxygen supply in the house, supplied by cylindersrather than an oxygen concentrator, powered to detect a reduction in admissions to hospital, and (2) astudy of bed-bound patients with heart failure who are in the last few weeks of life, powered to detectchanges in symptom severity.Trial registration: Current Controlled Trials ISRCTN60260702.Funding: This project was funded by the NIHR Health Technology Assessment programme and will bepublished in full in Health Technology Assessment; Vol. 19, No. 75. See the NIHR Journals Library websitefor further project information

Outcomes of acute exacerbations in COPD in relation to pre-hospital oxygen therapy

BACKGROUND: Pre-hospital, high-concentration oxygen therapy during acute exacerbation of chronic obstructive pulmonary disease (AECOPD) has been associated with increased mortality. Recent COPD guidelines have encouraged titrated oxygen therapy with a target saturation range of 88–92%. Oxygen therapy leading to saturation above 92% is defined as ‘inappropriate oxygen therapy’. OBJECTIVES: To examine the frequency of inappropriate oxygen therapy and whether inappropriate oxygen therapy in the ambulance in an urban area with short transit time to hospital was associated with poor outcome. METHODS: In an audit of 405 consecutive patients with AECOPD arriving by ambulance to Hvidovre Hospital, details of transit time, oxygen administration, saturation, and arterial blood gases were registered. Outcomes were respiratory acidosis, need of supported ventilation, length of hospitalisation, and in-hospital mortality. RESULTS: Only 15 patients were not treated with oxygen and information on oxygen flow was missing in seven patients and on saturation on one patient. Altogether, 352 (88.7%) of 397 patients received inappropriate oxygen therapy. Patients on ‘inappropriate oxygen therapy’ (saturation ≥92%) had a high frequency of respiratory acidosis at hospital admission, 108 (33.5%) of 324 patients, length of stay was on average 5.1 days, 12.5% of the patients needed ventilatory support, and in-hospital mortality was 3.4%. CONCLUSION: The majority of patients with AECOPD received inappropriate oxygen therapy in the ambulance, but their need of ventilatory support, length of stay, and mortality were low. Randomised studies are needed to clarify the optimal pre-hospital oxygen therapy