Table 4

 Logistic regression analysis

VariableOdds ratio (95% CI)p Value
The following variables were not found to be independent predictors of mortality: duration in hours in hospital before ventilation (p = 0.09); alveolar-arterial oxygen (A-a) gradient (p = 0.86); age (p = 0.55).
Type of respiratory failure2.69 (1.20 to 6.00)0.016
Use of inotropes2.39 (1.10 to 5.30)0.035
APACHE II score * for a five point increase in score1.80* (1.67 to 1.87)0.008