Step 2 of the All-Wales Acute Exacerbation of COPD Guideline focuses on categorising a patient according to presence of sputum purulence; with increased sputum purulence or without sputum purulence. For patients without increased sputum purulence, proceed to manage their exacerbation without antibiotics; breathlessness techniques, increase SABA (2 puffs QDS), consider Prednisolone. For patients with increased sputum purulence, proceed down the pathway to steps 4 and 5.

Check out this Tutorial from Simon, who explores this further.