Table 2

 Initial settings of non-invasive ventilation and blood gas responses (n = 110)

Data are expressed as mean (SD) unless otherwise specified.
IQR, interquartile range; IPAP, inspiratory positive airway pressure; EPAP, expiratory positive airway pressure; Pao2, Paco2, arterial oxygen and carbon dioxide tensions; Fio2, fraction of inspired oxygen.
IPAP (cm H2O)16.2 (2.8)
EPAP (cm H2O)6.2 (2.0)
Fio2 (%)38.6 (10.8)
No of days on NIV (median, IQR)5 (3–7)
First hour
    pH7.28 (0.07)
    Paco2 (kPa)9.9 (2.1)
Day 1
    pH7.34 (0.07)
    Paco2 (kPa)9.0 (1.9)