应用Bayesian反馈法预测老年患者头孢唑啉的药动学参数

 目的 应用Bayesian反馈法预测头孢唑啉在老年患者体内的药动学参数及血药浓度。方法 用HPLC测定头孢唑啉血药浓度。以1，2个实测血药浓度作为反馈，用Bayesian反馈法拟合估算老年患者的个体药动学参数，并与非老年患者比较。结果 老年组10例的CL为(60.1±17.3) mL·h^-1·kg^-1，V_d为(0.21±0.07) L·kg^-1，t_1/2为(2.6±0.8)h；非老年组10例分别为CL(87.6±34.4) mL·h^-1·kg^-1，V_d(0.19±0.08) L·kg^-1和t_1/2(1.5±0.4) h。二组CL，t_1/2之间的差异有显著意义(P＜0.05)，Vd之间差异则无显著意义(P＞0.05)。血药浓度预测值与实测值有良好的相关性(r＝0.997)。结论 老年患者随增龄CL降低，t_1/2延长，而Vd不变。用Bayesian反馈法估算的药动学参数可用于预测血药浓度及优化个体化给药方案。

Bayesian forecasting of cefazolin pharmacokinetics in elderly

OBJECTIVE To forecast the individual pharmacokinetic parameters of cefazolin in elderly patients with infecton by Bayesian approach.METHODS The cefazolin concentration in serum was measured by HPLC.Using 1 or 2 measured drug concentrations,the individual pharmacokinetic parameters were estimated by Bayesian feedback method,and then compared with those of non elderly patients.RESULTS The pharmacokinetic parameters in 10 elderly and 10 non elderly were CL(60.1±17.3),(87.6±34.4) mL·h^-1·kg^-1，V_d(0.21±0.07),(0.19±0.08) L·kg^-1，t_1/2(2.6±0.8),(1.5±0.4) h,respectively.There was significant difference in CL and t_1/2 parameters between the two groups (P＜0.05).No significant difference was found in Vd parameter (P＞0.05).CONCLUSION The pharmacokinetic parameters estimated by Bayesian approach was similar compared with the parameters eatimated by traditional method.It is suitable for forecasting plasma concentration and optimizing individualizing dosage regimens.