In this study, the investigators would like to investigate (in an exploratory way due to the non-interventional setup) whether weaning from mechanical ventilation will be affected by the choice of sedatives - including dexmedetomidine, midazolam and propofol. This study also aims at investigating how the choice of primary sedative will affect delirium/anxiety, need of other medications (sedatives, analgesics, anti-psychotics), quality of life after ICU and the presence of Post-Traumatic Stress Disorder. In addition, the investigators aim at receiving information from the caregivers on their ICU experience, as recent data imply that not only the ICU patient but also the caregiver suffer from PTSD after the ICU stay.