Description of Optimized Standard Care for COPD Exacerbations. All patients will receive standardized, optimized care for AECOPD. Nebulized albuterol (2.5 mg in 0.5 ml, dilute to 3 ml NSS administered every 4-6 hours) and ipratropium bromide (0.5 mg in 0.5 ml, diluted with 2.5 ml of saline administered every 6 hours) will be given. A 14-day course of systemic steroids consisting of intravenous methylprednisolone 125 mg every 6 hours for up to 72 hours, followed by once daily oral prednisone 60mg/day for days 4-7, 40 mg prednisone days 8-11 and 20 mg prednisone days 12-14 will be provided. A 7-day course of antibiotics will be selected based on patient's medical allergy history and relevant culture data if available. Supplemental oxygen will be provided by route and dose to achieve maximum patient comfort and compliance to maintain a SaO2 > 92%. Noninvasive positive pressure ventilation will be utilized at the discretion of the treating physicians but will follow accepted guidelines.