(i) 75 MV adults with 85 episodes of DEX infusion. (ii) Included 50 Caucasian and 15 Black patients.
To describe rates of DEX intolerance/failure and identify patient predictors of intolerance/failure.
(i) All patients received DEX titrated by the bedside nurse from 0.2 mcg/kg/h to a maximum of 1.5 mcg/kg/h to achieve targeted sedation with rescue fentanyl, midazolam, and propofol permissible. (ii) Individual episodes of DEX infusions were analyzed for predefined descriptions of intolerance and failure. (iii) Multivariate logistic regression analysis was used to identify predictors of intolerance or failure.
(i) 18 episodes (21%) were classified as intolerance/failure. 67 episodes (79%) were classified as successful. (ii) No significant difference between success and intolerance groups in additional sedation use was noted. (iii) Non-Black race was found to be statistically significant (adjusted odds ratio 9.5; 95% CI 1.16–77.91; ) as a predictor of failure/intolerance. The clinical significance of this was questionable.
(i) 73 healthy individuals. (ii) Included 37 Caucasian and 36 Black patients.
To evaluate the clinical effect of ethnicity on CV effects by changes in BP and HR and plasma NE concentrations.
(i) Patients received 3 placebo infusions then 3 DEX infusions (0.1, 0.15, 0.15 mcg/kg for total of 0.4 mcg/kg). (ii) BP, HR, and plasma NE concentrations were measured at the end of the infusion then 10 min and 20 min after. (iii) DEX plasma levels were measured after the last infusion of DEX. (iv) Patients were grouped into ADRA-2C del322-325 or no deletion and GNB3 C825T or no polymorphism.
(i) No significant differences in BP, HR, and plasma NE concentrations for ethnicity were detected. (i) Black patients had a higher plasma DEX concentration than white patients (mean ethnic difference 0.05 ng/mL; 95% CI, 0.03 to 0.07 ng/mL).
To identify patient specific characteristics that affect achievement of successful sedation with DEX.
(i) All patients received DEX to achieve targeted sedation based upon unit sedation protocol. (ii) Doses ranged from 0.3 mcg/kg/hr to 1.4 mcg/kg/hr with rescue propofol, fentanyl, and benzodiazepines allowed. (iii) Individual episodes of DEX infusions were analyzed for predefined descriptions of intolerance and failure. (iv) Multivariate logistic regression analysis used to identify predictors of intolerance or failure.
(i) DEX was ineffective in 19 (50%) patients. It was effective in 11 (28.95%) patients. In the remaining patients (), an analysis was unable to be completed. (ii) No significant difference between success and intolerance groups in additional sedation use was noted. (iii) Lower APACHE II score ( coefficient −0.24; 95% CI, −0.39 to −0.03) and home antidepressant use ( coefficient 2.33; 95% CI, 0.23 to 4.43) were identified as positive patient specific characteristics.
