The effectiveness of β2-agonists in the treatment of exacerbations of COPD is already established. The purpose of this study is to compare the effectiveness of the β2-agonists alone in nebulization with the association β2-agonists + Ipratropium bromide in the treatment of an acute exacerbation of COPD consulting the emergency departement based on the clinical and arterial blood gas.

It is a prospective study and randomized performed in patients admitted to the emergency departement for acute exacerbation of COPD. The patients were divided in two groups: Group Terbutaline/Ipratropium Bromide; received Terbutaline + Ipratropium bromide in nebulization and Group Terbutaline received Terbutaline alone in nebulization)

Inclusion Criteria:

• have known or suspected COPD based on pulmonary function test, arterial blood gas, clinical history, physical examination, and chest radiograph
• Age over 18 years old.
• COPD Exacerbation: sustained worsening of patient's condition from stable state necessitating change in regular medication within the last two weeks and need for non invasive ventilation with regard to arterialo blood gas abnormalities: PaCO2 > 45 mmHg, PH<7,35 SaO2<90%

Exclusion Criteria:

• GCS ≤ 14
• hypersensitivity to anticholinergic
• severe acidosis
• immediate need for intubation
• lack of patient cooperation
• serious hemodynamic unstability or systolic blood pressure < 90 mmHg, heart arrhythmia