A 78-year-old man with COPD (FEV1 45% predicted) presents with increasing dyspnoea, cough and purulent sputum for 3 days. He is afebrile, oxygen saturation is 92% on room air and chest X-ray shows no new consolidation. In addition to optimising bronchodilators and considering antibiotics, what systemic corticosteroid regimen is recommended in Australian practice for a moderate COPD exacerbation managed as an inpatient?