Delirium is one of main adverse events in ventilated patients who receive long-term usage of mono-sedative. Sequential sedation may reduce these adverse effects. This study aimed to evaluate incidence and risk factors for delirium in sequential sedation patients.

Previous studies have showed that patients under mechanical ventilation have a higher risk for experiencing delirium than nonmechanically ventilated patients (20%-50%). Its occurrence is also more frequent in elder patients. More than that, it is often hard to identify delirium by physicians, leading to unreasonable management of ICU patients.

And delirium is one of main adverse events in ventilated patients who receive long-term usage of mono-sedative. Sequential sedation may reduce these adverse effects.

However, few present studies focus on delirium in sequential sedation patients. Thus, in this study, we aimed to determine the factors of delirium in patients who received sequential sedation in ICU.

Inclusion Criteria:

1. Intubated patients;
2. Age≥18 years old;
3. Anticipated Ventilation and sedation duration of at least 72 hours.

Exclusion Criteria:

1. Allergy to the study drug;
2. suspected pregnancy;
3. gross obesity;
4. Extremely unstable of circulatory system, such as systolic blood pressure less than 90 mm Hg despite plasma volume expansion and continuous infusions of vasopressors before the start of study drug infusion;
5. Uncontrolled abnormal hypertension, such as systolic blood pressure more than 180 mmHg or diastolic more than105 mmHg;
6. Heart rate less than 50 bpm;
7. Second or third degree heart block;
8. moribund state;
9. history of alcoholism or intake of anti-anxiety drugs or hypnotics;
10. chronic renal failure;
11. coma by cranial trauma or neurosurgery or unknown etiology or epileptic state;
12. History of neuromuscular disease;
13. unwillingness to provide informed consent by patients or their authorized surrogates following ICU admission.

All patients with an age greater than 18 years old and less than 80 years old, who were expected to receive mechanical ventilation longer than 72 hours and accepted sedation therapy were recruited on admission to the ICU.