Given that the patient has large bullous emphysema in the left upper lobe, the findings in the right upper lobe are likely due to bullous emphysema. The air/fluid level is presumed to represent infected fluid as the patient had been unwell with septic symptoms for some time and is coughing up green sputum. Adjacent lung consolidation. The lack of response to antibiotics indicates that surgical drainage and even bulla excision will be required. 

"Smoking pack years" is calculated by multiplying the number of packs of cigarettes smoked per day by the number of years the person has smoked.