Objectives To determine the effectiveness of non-invasive positive pressure ventilation (NPPV) in the management of respiratory failure secondary to acute exacerbation of chronic obstructive pulmonary disease. Design Systematic review of randomised controlled trials that compared NPPV and usual medical care with usual medical care alone in patients admitted to hospital with respiratory failure resulting from an exacerbation of chronic obstructive pulmonary disease and with PaCO 2 > 6 kPa. Results The eight studies included in the review showed that, compared with usual care alone, NPPV as an adjunct to usual care was associated with a lower mortality (relative risk 0.41 (95% confidence interval 0.26 to 0.64)), a lower need for intubation (relative risk 0.42 (0.31 to 0.59)), lower likelihood of treatment failure (relative risk 0.51 (0.38 to 0.67)), and greater improvements at 1 hour in pH (weighted mean difference 0.03 (0.02 to 0.04)), PaCO 2 (weighted mean difference − 0.40 kPa ( − 0.78 to − 0.03)), and respiratory rate (weighted mean difference − 3.08 breaths per minute ( − 4.26 to − 1.89)). NPPV resulted in fewer complications associated with treatment (relative risk 0.32 (0.18 to 0.56)) and shorter duration of stay in hospital (weighted mean difference − 3.24 days ( − 4.42 to − 2.06)). Conclusions NPPV should be the first line intervention in addition to usual medical care to manage respiratory failure secondary to an acute exacerbation of chronic obstructive pulmonary disease in all suitable patients. NPPV should be tried early in the course of respiratory failure and before severe acidosis, to reduce mortality, avoid endotracheal intubation, and decrease treatment failure.

et al. Comparison of the effectiveness of inhaler devices in asthma and chronic obstructive airways disease: a systematic review of the literature. Health Technol Assess 2001;5(26). Health Technology Assessment is indexed in Index Medicus/MEDLINE and Excerpta Medica/ EMBASE. Copies of the Executive Summaries are available from the NCCHTA website (see opposite). NHS R&D HTA Programme T he NHS R&D Health Technology Assessment (HTA) Programme was set up in 1993 to ensure that high-quality research information on the costs, effectiveness and broader impact of health technologies is produced in the most efficient way for those who use, manage and provide care in the NHS. Initially, six HTA panels (pharmaceuticals, acute sector, primary and community care, diagnostics and imaging, population screening, methodology) helped to set the research priorities for the HTA Programme. However, during the past few years there have been a number of changes in and around NHS R&D, such as the establishment of the National Institute for Clinical Excellence (NICE) and the creation of three new research programmes: Service Delivery and Organisation (SDO); New and Emerging Applications of Technology (NEAT); and the Methodology Programme. This has meant that the HTA panels can now focus more explicitly on health technologies ('health technologies' are broadly defined to include all interventions used to promote health, prevent and treat disease, and improve rehabilitation and long-term care) rather than settings of care. Therefore the panel structure has been redefined and replaced by three new panels: Pharmaceuticals; Therapeutic Procedures (including devices and operations); and Diagnostic Technologies and Screening. The HTA Programme will continue to commission both primary and secondary research. The HTA Commissioning Board, supported by the National Coordinating Centre for Health Technology Assessment (NCCHTA), will consider and advise the Programme Director on the best research projects to pursue in order to address the research priorities identified by the three HTA panels. The research reported in this monograph was funded as project number 97/23/02. The views expressed in this publication are those of the authors and not necessarily those of the HTA Programme or the Department of Health. The editors wish to emphasise that funding and publication of this research by the NHS should not be taken as implicit support for any recommendations made by the authors. Criteria for inclusion in the HTA monograph series Reports are published in the HTA monograph series if (1) they have resulted from work commissioned for the HTA Programme, and (2) they are of a sufficiently high scientific quality as assessed by the referees and editors. Reviews in Health Technology Assessment are termed 'systematic' when the account of the search, appraisal and synthesis methods (to minimise biases and random errors) would, in theory, permit the replication of the review by others.

Data from good quality randomised controlled trials show benefit of NPPV as first line intervention as an adjunct therapy to usual medical care in all suitable patients for the management of respiratory failure secondary to an acute exacerbation of COPD. NPPV should be considered early in the course of respiratory failure and before severe acidosis ensues, as a means of reducing the likelihood of endotracheal intubation, treatment failure and mortality.

Objectives To evaluate the efficacy of hospital at home schemes compared with inpatient care in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD). Design A systematic review of randomised controlled trials. Main outcome measure Mortality and readmission to hospital. Results Seven trials with 754 patients were included in the review. Hospital readmission and mortality were not significantly different when hospital at home schemes were compared with inpatient care (relative risk 0.89, 95% confidence interval 0.72 to 1.12, and 0.61, 0.36 to 1.05, respectively). However, compared with inpatient care, hospital at home schemes were associated with substantial cost savings as well as freeing up hospital inpatient beds. Conclusions Hospital at home schemes can be safely used to care for patients with acute exacerbations of COPD who would otherwise be admitted to hospital. Clinicians should consider this form of management, especially as there is increasing pressure for inpatient beds in the United Kingdom.

This review shows that in COPD exacerbations with increased cough and sputum purulence antibiotics, regardless of choice, reduce the risk of short-term mortality by 77%, decrease the risk of treatment failure by 53% and the risk of sputum purulence by 44%; with a small increase in the risk of diarrhoea. These results should be interpreted with caution due to the differences in patient selection, antibiotic choice, small number of included trials and lack of control for interventions that influence outcome, such as use of systemic corticosteroids and ventilatory support. Nevertheless, this review supports antibiotics for patients with COPD exacerbations with increased cough and sputum purulence who are moderately or severely ill.