Table 1
Commonly quoted predictive variables of weaning
8
Variable
Threshold value
Sensitivity
Specificity
Threshold value=value beyond which weaning is predicted to fail.
Minute ventilation
15 l/min
0.78
0.18
Maximum inspiratory pressure
–15 cm H
2
O
0.97
0.36
Tidal volume
4 ml/kg
1.00
0.11