老年全麻手术患者右美托咪定药代动力学研究

Pharmacokinetics of Dexmedetomidine in Elderly General Anesthesia Patients

目的研究右美托咪定在手术麻醉患者中的药代动力学,为右美托咪定的临床评价、监测及在ICU中的推广提供实验依据。方法老年手术患者10例,静脉给予右美托咪定0.5μg·kg^(-1),分点采集血样,使用液质联用法(LC-MS/MS)测定右美托咪定血药浓度,计算药代动力学参数。结果患者的主要药代动力学参数为AUC_(0-8) 1235.01±12.33h·ng·L^(-1),C_(max) 494.81±24.4ng·L^(-1),t_(1/2α) 0.80±0.03h,t_(1/2β) 2.41±0.08h。结论老年人右美托咪定的药代动力学与文献报道的中青年相近,因此老年人使用右美托咪定后的不良反应可能与代谢酶基因多态性或其他作用机制等相关。

OBJECTIVE To investigate the pharmacokinetics of dexmedetomidine in elderly anesthesia pa- tients, and provide experimental basis for dexmedetomidine＇ s clinical evaluation, monitoring and furtherly being applied in ICU. METHODS 10 cases of elderly surgery patients were administrated 0. 5 μg · kg-1 dexmedetomidine intravenously, and the blood samples were collected at different times. The concentration of dexmedetomidine in blood was determined by LC-MS/MS, and the pharmacokinetic parameters were calculated. RESULTS The main pharmaeokinetic parameters were as follows： AUC0-8 1235.01 ± 12.33h · ng · mL-1 , Cmax, 494. 81 ± 24. 4ng · mL-1 , t1/2α 0. 80 ± 0. 03h, t1/2β 2. 41 ± 0. 08h. CONCLUSION The pharmacokinetic parameters of elderly patients were close to that of young patients reported in literature. Therefore, the adverse effects of dexmedetomidine in the elderly may be related to the genetic polymorphisms of metabolic enzymes or other mechanisms of action.