Table 1 Baseline characteristics of the patients

Age (years)

63.4 ± 13.2

Sex (m/f)

12/7

SAPS II

50 ± 9

Midazolam cumulative amount in the previous 24 hours (mg)

133 ± 128

Sufentanyl cumulative amount in the previous 24 hours (μg)

253 ± 225

Duration of MV (days)

10.4 ± 6.8

Indication for mechanical ventilation^a

Acute respiratory failure (n = 7)

Acute exacerbation of chronic respiratory impairment (n = 4)

Toxic coma (n = 4)

Sepsis (n = 3)

Postoperative respiratory failure (n = 1)