Table 2

Combined data from both audits highlighting the mortality rate in acidotic versus non-acidotic patients, according to time to NIV

Time to NIVMortality rate in patients acidotic on admissionMortality rate of patients non-acidotic on admissionP value
<60 min68/414=16.4%4/56=7.1%0.092
60–179 min69/448=15.4%8/55=14.5%0.068
3–24 hours94/510=18.4%44/231=19%0.842
>24 hours39/135=28.9%103/242=42.6%0.009
Overall Mortality (regardless of time to NIV)318/1770=18.0%172/699=24.6%<0.001
Median hours between first and second ABG1.85.6<0.001
Median hours from second ABG to NIV0.222<0.001
  • ABG, arterial blood gas; NIV, non-invasive ventilation.