Corticosteroids do indeed work for severe COPD exacerbations (RCT, Arch Intern Med)
When given to people with acute exacerbations of chronic obstructive pulmonary disease, corticosteroids aren't proven to reduce mortality, but they improve FEV1, reduce hospitalization by ~1 day, and increase 30-day treatment success, according to a 2009 Cochrane review of 10 randomized trials. Patients in ICUs were excluded from the analyzed studies, and it's unclear whether steroids are helpful or harmful in that setting. An 8 ICU multicenter randomized placebo controlled trial in Spain (Andres Esteban), Mexico, Colombia, and at the University of Texas in San Antonio (Antonio Anzueto) was done to answer that question. They found among 83 patients:
The 43 patients who got steroids spent one less day on the ventilator than the 40 who got placebo (3 vs. 4 days, p=0.04).
Providing placebo instead of corticosteroids appeared to lead to 7 of 19 patients (37%) failing non-invasive ventilation and undergoing intubation and mechanical ventilation (zero of 18 patients receiving steroids failed noninvasive ventilation, p=0.04).
There was no detected difference in mortality.
Twice as many steroid-treated patients had hyperglycemia (46% vs. 25%, with a conservative cutoff of blood glucose > 120 mg/dL), but there were no real adverse events attributable to steroids.
These findings were apparent despite only enrolling 83 patients of a planned 198 believed necessary to achieve the desired power. The study took 5 years, mainly because so many patients had received steroids recently (within 30 days or in the emergency department), excluding them.
Alia I et al. Efficacy of Corticosteroid Therapy in Patients With an Acute Exacerbation of Chronic Obstructive Pulmonary Disease Receiving Ventilatory Support. Arch Intern Med 2011;171:1939-1946.