DESIGN: Harmonized data from prospective multicenter international longitudinal cohort studies SETTING:: Diverse mix of ICUs.
PATIENTS: Critically ill patients expected to be ventilated for longer than 24 hours.
INTERVENTIONS: Richmond Agitation Sedation Scale and pain were assessed every 4 hours. Delirium and mobilization were assessed daily using the Confusion Assessment Method of ICU and a standardized mobility assessment, respectively.
MEASUREMENTS AND MAIN RESULTS: Sedation intensity was assessed using a Sedation Index, calculated as the sum of negative Richmond Agitation Sedation Scale measurements divided by the total number of assessments. We used multivariable Cox proportional hazard models to adjust for relevant covariates. We performed subgroup and sensitivity analysis accounting for immortal time bias using the same variables within 120 and 168 hours. The main outcome was 180-day survival. We assessed 703 patients in 42 ICUs with a mean (SD) Acute Physiology and Chronic Health Evaluation II score of 22.2 (8.5) with 180-day mortality of 32.3% (227). The median (interquartile range) ventilation time was 4.54 days (2.47-8.43 d). Delirium occurred in 273 (38.8%) of patients. Sedation intensity, in an escalating dose-dependent relationship, independently predicted increased risk of death (hazard ratio [95% CI], 1.29 [1.15-1.46]; p < 0.001, delirium hazard ratio [95% CI], 1.25 [1.10-1.43]), p value equals to 0.001 and reduced chance of early extubation hazard ratio (95% CI) 0.80 (0.73-0.87), p value of less than 0.001. Agitation level independently predicted subsequent delirium hazard ratio [95% CI], of 1.25 (1.04-1.49), p value equals to 0.02. Delirium or mobilization episodes within 168 hours, adjusted for sedation intensity, were not associated with survival.
CONCLUSIONS: Sedation intensity independently, in an ascending relationship, predicted increased risk of death, delirium, and delayed time to extubation. These observations suggest that keeping sedation level equivalent to a Richmond Agitation Sedation Scale 0 is a clinically desirable goal.
METHODS: Bayesian analysis of 3904 critically ill adult patients expected to receive invasive ventilation > 24 h and enrolled in a multinational randomized controlled trial comparing early DEX with usual care sedation.
RESULTS: HTE was assessed according to age and clusters (based on 12 baseline characteristics) using a Bayesian hierarchical models. DEX was associated with lower 90-day mortality compared to usual care in patients > 65 years (odds ratio [OR], 0.83 [95% credible interval [CrI] 0.68-1.00], with 97.7% probability of reduced mortality across broad categories of illness severity. Conversely, the probability of increased mortality in patients ≤ 65 years was 98.5% (OR 1.26 [95% CrI 1.02-1.56]. Two clusters were identified: cluster 1 (976 patients) mostly operative, and cluster 2 (2346 patients), predominantly non-operative. There was a greater probability of benefit with DEX in cluster 1 (OR 0.86 [95% CrI 0.65-1.14]) across broad categories of age, with 86.4% probability that DEX is more beneficial in cluster 1 than cluster 2.
CONCLUSION: In critically ill mechanically ventilated patients, early sedation with dexmedetomidine exhibited a high probability of reduced 90-day mortality in older patients regardless of operative or non-operative cluster status. Conversely, a high probability of increased 90-day mortality was observed in younger patients of non-operative status. Further studies are needed to confirm these findings.
METHODS: In an open-label, randomized trial, we enrolled critically ill adults who had been undergoing ventilation for less than 12 hours in the ICU and were expected to continue to receive ventilatory support for longer than the next calendar day to receive dexmedetomidine as the sole or primary sedative or to receive usual care (propofol, midazolam, or other sedatives). The target range of sedation-scores on the Richmond Agitation and Sedation Scale (which is scored from -5 [unresponsive] to +4 [combative]) was -2 to +1 (lightly sedated to restless). The primary outcome was the rate of death from any cause at 90 days.
RESULTS: We enrolled 4000 patients at a median interval of 4.6 hours between eligibility and randomization. In a modified intention-to-treat analysis involving 3904 patients, the primary outcome event occurred in 566 of 1948 (29.1%) in the dexmedetomidine group and in 569 of 1956 (29.1%) in the usual-care group (adjusted risk difference, 0.0 percentage points; 95% confidence interval, -2.9 to 2.8). An ancillary finding was that to achieve the prescribed level of sedation, patients in the dexmedetomidine group received supplemental propofol (64% of patients), midazolam (3%), or both (7%) during the first 2 days after randomization; in the usual-care group, these drugs were administered as primary sedatives in 60%, 12%, and 20% of the patients, respectively. Bradycardia and hypotension were more common in the dexmedetomidine group.
CONCLUSIONS: Among patients undergoing mechanical ventilation in the ICU, those who received early dexmedetomidine for sedation had a rate of death at 90 days similar to that in the usual-care group and required supplemental sedatives to achieve the prescribed level of sedation. More adverse events were reported in the dexmedetomidine group than in the usual-care group. (Funded by the National Health and Medical Research Council of Australia and others; SPICE III ClinicalTrials.gov number, NCT01728558.).