Table 3

Relative risk of failure judged at enrolment compared with a patient with a pH of 7.35 and Paco 2 6 kPa treated without NIV

pHTreatmentPaco2
6 kPa8 kPa10 kPa12 kPa
7.35Standard1.001.301.692.19
+ NIV0.390.510.660.86
7.30Standard2.963.845.006.49
+ NIV1.151.501.952.53
7.25Standard9.9812.9716.8521.90
+ NIV3.895.066.578.54