RESUMEN
INTRODUCTION: The effectiveness of non-invasive positive pressure ventilation (NIV) in COPD patients with prolonged hypercapnia after ventilatory support for acute respiratory failure (ARF) remains unclear. We investigated if nocturnal NIV in these patients prolongs the time to readmission for respiratory causes or death (primary endpoint) in the following 12â months. METHODS: 201 COPD patients admitted to hospital with ARF and prolonged hypercapnia >48â h after termination of ventilatory support were randomised to NIV or standard treatment. Secondary outcomes were daytime arterial blood gasses, transcutaneous PCO2 during the night, lung function, health-related quality-of-life (HRQL), mood state, daily activities and dyspnoea. RESULTS: 1â year after discharge, 65% versus 64% of patients (NIV vs standard treatment) were readmitted to hospital for respiratory causes or had died; time to event was not different (p=0.85). Daytime PaCO2 was significantly improved in NIV versus standard treatment (PaCO2 0.5 kPa (95% CI 0.04 to 0.90, p=0.03)) as was transcutaneous PCO2 during the night. HRQL showed a trend (p=0.054, Severe Respiratory Insufficiency questionnaire) in favour of NIV. Number of exacerbations, lung function, mood state, daily activity levels or dyspnoea was not significantly different. DISCUSSIONS: We could not demonstrate an improvement in time to readmission or death by adding NIV for 1â year in patients with prolonged hypercapnia after an episode of NIV for ARF. There is no reason to believe the NIV was not effective since daytime PaCO2 and night-time PCO2 improved. The trend for improvement in HRQL favouring NIV we believe nevertheless should be explored further. TRIAL REGISTRATION NUMBER: NTR1100.
Asunto(s)
Hipercapnia/terapia , Ventilación no Invasiva , Readmisión del Paciente , Enfermedad Pulmonar Obstructiva Crónica/terapia , Enfermedad Aguda , Afecto , Anciano , Análisis de los Gases de la Sangre , Dióxido de Carbono , Progresión de la Enfermedad , Disnea/etiología , Femenino , Volumen Espiratorio Forzado , Humanos , Hipercapnia/complicaciones , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Actividad Motora , Presión Parcial , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Intercambio Gaseoso Pulmonar , Calidad de Vida/psicología , Insuficiencia Respiratoria/complicaciones , Insuficiencia Respiratoria/terapia , Factores de TiempoRESUMEN
BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (AE-COPD) are related to high mortality, especially in hospitalized patients. Predictors for severe outcomes are still not sufficiently defined. OBJECTIVES: To assess the mortality rate and identify potential determinants of mortality in a cohort of patients hospitalized for AE-COPD. METHODS: A retrospective, observational cohort study including all consecutive patients admitted between January 1, 2009, and April 1, 2010, for AE-COPD. Potential predictors were assessed at initial presentation at the emergency room. The primary outcome was mortality during 1-year follow-up. Univariate and multivariate time-to-event analyses using Cox proportional hazard models were employed for statistical analysis. RESULTS: A total of 260 patients were enrolled in this study. Mean age was 70.5 ± 10.8 years, 50.0% were male and 63.4% had severe COPD. The in-hospital mortality rate was 5.8% and the 1-year mortality rate was 27.7%. Independent risk factors for mortality were age [hazard ratio (HR) = 1.04; 95% confidence interval (CI) = 1.01-1.07], male sex (HR = 2.00; 95% CI = 1.15-3.48), prior hospitalization for AE-COPD in the last 2 years (HR = 2.56; 95% CI = 1.52-4.30), prior recorded congestive heart failure (HR = 1.75; 95% CI = 1.03-2.97), PaCO2 ≥6.0 kPa (HR = 2.90; 95% CI = 1.65-5.09) and urea ≥8.0 mmol/l (HR = 2.38; 95% CI = 1.42-3.99) at admission. CONCLUSIONS: Age, male sex, prior hospitalization for AE-COPD in the last 2 years, prior recorded congestive heart failure, hypercapnia and elevated levels of urea at hospital admission are independent predictors of mortality within the first year after admission.