Predictors of outcomes in COPD exacerbation cases presenting to the emergency department

The aim of the present prospective multicentric study was to develop a simple rule for the prediction of poor outcome in patients presenting to emergency departments with initially non-life threatening-chronic obstructive pulmonary disease (COPD) exacerbations in a real-life setting. All patients with an acute exacerbation of COPD visiting the emergency departments of 103 hospitals during a 3-month period were included, except those who immediately required intensive care unit admission and/or ventilatory support. The data collected included patient characteristics, in-hospital outcomes (mortality and length of stay) and mode of discharge (unsupported or need for post-hospital assistance). The in-hospital mortality rate was 7.4% (59 out of 794). Independent prognostic factors were age, number of clinical signs of severity (among cyanosis, impaired neurological status, lower limb oedema, asterixis and use of accessory inspiratory or expiratory muscles) and dyspnoea grade in the stable state. The need for post-hospital support was also predicted by female sex. In order to construct and validate a prediction score for mortality based on these items, patients were randomly allocated to a derivation and a validation cohort. The prediction score showed good discrimination, with a c-statistic of 0.79 in the derivation cohort and 0.83 in the validation cohort. Thus simple purely clinical factors can reliably predict the risk of death and requirement for post-hospital support in an initially non-life threatening-acute exacerbation of chronic obstructive pulmonary disease. Their use needs to be prospectively validated.