Pulmоnаry clinic fоllоw-up. The client hаs severe COPD аnd takes tiotropium once daily, albuterol as needed and home oxygen at 2 L/min. The spouse reports the client has been sleeping more and using albuterol every 2 hours since a cold began 4 days ago. Finding 3 months ago Today pH 7.38 7.30 PaCO2 (mm Hg) 50 66 PaO2 (mm Hg) 60 51 HCO3− (mEq/L) 29 30 Hgb (g/dL) 18.1 18.3 Chest x-ray Flattened diaphragm, hyperinflation No change Which result should the nurse act on first?