Adult Disease, Delirium, Dexmedetomidine, Intensive Care Unit Syndrome, Mechanical Ventilation Complication
Conditions
Keywords
Adult, Intensive care unit, Mechanical ventilation, Delirium, Dexmedetomidine
Brief summary
For patients undergoing mechanical ventilation, light sedation is better than deep sedation for the outcomes, which is manifested as shortened length of ICU stay, shortened duration of mechanical ventilation, and decreased mortality. In a recent study of the investigators, low-dose dexmedetomidine without sedative effects (0.1 ug/kg/h) improved sleep quality and reduced the incidence of delirium in elderly patients admitted to the ICU after surgery. The investigators hypothesize that, for ICU patients with prolonged mechanical ventilation, low-dose dexmedetomidine infusion (0.1 ug/kg/h) may also be effective in decreasing delirium. The purpose of this study is to investigate whether low-dose dexmedetomidine infusion can reduce the incidence of delirium in ICU patients with prolonged duration of mechanical ventilation (\>= 24 hours).
Detailed description
Delirium is an acutely occurred and transient brain dysfunction characterized with cognitive dysfunction, lowered consciousness, disturbed attention, abnormal psychoactivity, and disordered sleep-wake rhythm. Delirium is frequent in mechanically ventilated patients in the intensive care unit (ICU), with reported incidences up to 70% or 87%. Possible reasons leading to delirium include the intervention-heavy environment of the ICU, mechanical ventilation and sleep disturbances. The occurrence of delirium is associated with worse outcomes including prolonged mechanical ventilation and ICU stay, increased complications, prolonged hospital stay, higher mortality, and elevated medical expenses. It is also associated with worse long-term outcomes including declined cognitive function, lowered life quality, and elevated long-term mortality. Dexmedetomidine is a high selective alpha-2 adrenoceptor agonist with anxiolytic, sedative and analgesic effects. When used for sedation in mechanically ventilated patients (dose range 0.2-1.4 ug/kg/h), it reduces the consumption of other sedatives and analgesics, ameliorates the rhythm and structure of sleep, and decreases the occurrence of delirium. In recent studies of the investigators, low-dose dexmedetomidine infusion (0.1 ug/kg/h) ameliorated sleep quality; for elderly patients admitted to the ICU after surgery, prophylactic low-dose dexmedetomidine infusion reduced the incidence of delirium (for patients with mechanical ventilation: 28.8% with placebo vs. 11.5% with dexmedetomidine, P\<0.0001; for patients without mechanical ventilation: 15.1% with placebo vs. 6.3% with dexmedetomidine, P=0.014). For patients undergoing mechanical ventilation, light sedation is better than deep sedation for the outcomes, which is manifested as shortened length of ICU stay, shortened duration of mechanical ventilation, and decreased mortality. Some authors even reported that no sedation (analgesia only) provides better outcome than light sedation, because it further shortens the durations of mechanical ventilation and ICU stay. In the above studies of the investigators, the recruited patients were less severe because the Acute Physiology and Chronic Health Evaluation II (APACHE II) score was low (mean score from 10.2 to 10.6) and the duration of mechanical ventilation was short (median 6.9 hours in the control group). The investigators hypothesize that, for ICU patients with prolonged mechanical ventilation, low-dose dexmedetomidine infusion (0.1 ug/kg/h) may also be effective in improving sleep and decreasing delirium. The purpose of this study is to investigate whether low-dose dexmedetomidine infusion can reduce the incidence of delirium in ICU patients with prolonged duration of mechanical ventilation (\>= 24 hours).
Interventions
Dexmedetomidine is administered as a continuous intravenous infusion at a rate of 0.025 mL/kg per h (0.1 μg/kg per h) from study recruitment in the ICU for no more than 72 hours.
Placebo (normal saline) is administered as a continuous intravenous infusion at a rate of 0.025 mL/kg per h from study recruitment in the ICU for no more than 72 hours.
Sponsors
Study design
Eligibility
Inclusion criteria
* aged 18 years or older; * admitted to the ICU; * with expected duration of mechanical ventilation of more than 24 hours.
Exclusion criteria
* refused to participate; * aged less than 18 years; * pregnant; * preoperative history of schizophrenia, epilepsy, Parkinsonism, or myasthenia gravis; * inability to communicate in the preoperative period (coma, profound dementia, or language barrier); * brain injury or neurosurgery; * known preoperative left ventricular ejection fraction less than 30%, sick sinus syndrome, severe sinus bradycardia (\<50 beats per min \[bpm\]), or second degree or greater atrioventricular block without pacemaker; * severe hepatic dysfunction (Child-Pugh class C); * severe renal dysfunction (undergoing dialysis before surgery); * less likely to survive for more than 24 hours.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of delirium within the first 7 days after enrollment | From enrollment until 7 days. | Assessment twice daily (in the morning from 0600 h to 1000 h and in the evening from 1800 h to 2000 h) with the Confusion Assessment Method for the ICU (CAM-ICU). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Duration of mechanical ventilation | From enrollment until extubation or 30 days. | Duration of mechanical ventilation after study enrollment. |
| Length of stay in the ICU | From enrollment until ICU discharge or 30 days. | Length of stay in the ICU after study enrollment. |
| Length of stay in the hospital | From enrollment until hospital discharge or 30 days. | Length of stay in the hospital after study enrollment. |
| Occurrence of non-delirium complications | From enrollment until 30 days. | Occurrence of complications other than delirium after study enrollment. |
| 30-day cognitive function | On the 30th day after enrollment. | Assessed with the Telephone Interview of Cognitive Status-Modified (TICS-m). |
| 30-day life quality | On the 30th day after enrollment. | Assessed with the WHOQOL-Bref. |
| All-cause 30-day mortality | On the 30th day after enrollment. | All-cause 30-day mortality after study enrollment. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Pain intensity | From enrollment until 7 days. | Assessed twice daily (in the morning from 0600 h to 1000 h and in the evening from 1800 h to 2000 h) with the Numeric Rating Scale (NRS, an 11 point scale where 0 indicated no pain and 10 indicated the worst possible pain). |
| Subjective sleep quality | From enrollment until 7 days. | Assessed in the morning with the NRS (an 11 point scale where 0 indicated the best possible sleep and 10 indicated the worst possible sleep). |
Countries
China