The univariate analysis showed that the NPPV success subgroup had more patients with acute lung injury ( ALI ) ( 17 vs. 0 , P = 0.038 ) , fewer patients with pneumonia ( 2 vs. 7 , P < 0.001 ) and lower acute physiology and chronic health evaluation II ( APACHE II ) scores ( 16.1 2.8 vs. 21.8 3.2 , P < 0.001 ) .