The purpose of this study is to compare propofol-remifentanil sedation with midazolam-remifentanil sedation in regards to extubation and weaning time, length of stay in the ICU, as well as the incidence of delirium. Primary end-points were weaning time and extubation time, and secondary end-points were the incidence of delirium and length of stay in the ICU.

With on-going emphasis on early extubation, as well as further recognition of morbidity and mortality associated with delirium, the specific sedatives and analgesics used in the ICU is an issue of interest. Recent studies have focused on comparing sedatives, but interpretations are often confounded by the fact that in most studies, different analgesics were used when comparing two sedative medications. The role of remifentanil as the main analgesic in the ICU is being recognized. Pharmacodynamic and pharmacokinetic profiles of remifentanil makes it an ideal analgesic in the ICU setting. The investigators therefore designed this randomized study to compare sedation with propofol and midazolam in a remifentanil-based sedation and analgesia.

The purpose of this study is to compare propofol-remifentanil sedation with midazolam-remifentanil sedation in regards to extubation and weaning time, length of stay in the ICU, as well as the incidence of delirium. Primary end-points were weaning time and extubation time, and secondary end-points were the incidence of delirium and length of stay in the ICU.

Inclusion Criteria:

• surgical patients over 18 years old who were admitted to the ICU for postoperative ventilator care after sevoflurane-remifentanil based general anesthesia

Exclusion Criteria:

• pre-existing neurologic dysfunction (dementia)
• head trauma patients
• previous history of alcohol abuse or substance abuse
• patients who had baseline serum creatinin levels of over 2.5mg/100ml
• uncompensated liver cirrhosis
• hemorrhagic, cardiogenic, or septic shock
• pregnancy or breast feeding
• tracheostomy or extubation before ICU admission.