Figure 30.2.

Estimated mortality for groups of patients with acute exacerbations of COPD. A and B groups: refer to in-hospital and 30-day mortality;8, 9 C group: refers to early institution of NIV;8, 9 D group: refers to patients requiring IMV;⁹ E group: refers to hypercapnic AECOPD patients either failing NIV and needing IMV, or those identified late as requiring NIV;8, 9 F and G groups: weaned from IMV and randomised to either immediate NIV or not (i.e. randomised controlled trial) with in-hospital and 30-day mortality;⁴⁴ H group: 1-year mortality post NIV;⁷ I and J groups: effect of titrated versus untitrated oxygen at emergency department²³ and ambulance.²²