高效液相色谱法测定重症患者亚胺培南血药浓度及PK/PD达标率研究

Determination of plasma imipenem in critically ill patients by HPLC and research on PK/PD targeted attainment

目的:建立高效液相色谱法测定重症患者血浆中亚胺培南浓度,并将接受连续性肾脏替代疗法(continuous renal replacement therapy,CRRT)与未接受该疗法患者的结果进行对比,为临床调整用药提供依据。方法:以0.5 mol·L^(-1)的3-吗啉丙磺酸缓冲液(pH6~8)-乙二醇-水(2∶1∶1)为稳定剂,以5-羟基吲哚-3-乙酸为内标,采用超滤离心管去蛋白法进行前处理,取滤过液进样。色谱柱为TSKgel ODS-100V(4.6 mm×250 mm,5μm),流动相为甲醇-10 mmol·L^(-1)磷酸二氢钾(6∶94,磷酸调pH为6.7~7.0),流速为0.9 mL·min-1,检测波长为300 nm,柱温为30℃,进样量为30μL。测定分析33例接受亚胺培南/西司他丁治疗的重症患者的血药谷浓度,CRRT组14例,非CRRT组19例,以100%T>MIC作为PK/PD靶目标计算用药达标率,评估给药方案。结果:亚胺培南在0.5~50μg·mL^(-1)内线性关系良好,定量下限为0.5μg·mL^(-1);批内、批间RSD均小于10%;稳定性试验结果表明血浆样品在处理过程中较稳定。当MIC大于2μg·mL^(-1)时,达标率显著降低,且接受CRRT治疗患者的达标率低于未接受CRRT治疗患者。结论:该方法前处理过程简单,灵敏准确,分析时间短,适用于临床亚胺培南个体化用药指导。

OBJECTIVE To establish an HPLC method for the determination of imipenem in plasma of critically ill patients to compare the results of patients who received continuous renal replacement therapy（CRRT）with those who did not receive the therapy,and to provide evidences for drug adjustment.METHODS With 0.5 mol·L^-1 3-morpholine-propane sulfonic acid buffer（pH6-8）-ethylene-glycol-water（2∶1∶1）as the stabilizer,with5-hydroxy-indole-3 acetic acid as the internal standard,samples were deproteinized by centrifugation using ultrafiltration pretreatment tube.Separation was performed on a TSKgel ODS-100 V column（4.6 mm×250 mm,5μm）.The mobile phase was composed of methanol and 10 mmol·L^-1 KH2PO4（pH6.7-7.0,6∶94）with a flow rate of 0.9 mL·min^-1.The detection wavelength was 300 nm,the column temperature was 30 ℃,and the injection volume was 30μL.The method was applied in the determination of trough plasma imipenem concentrations from 33 critically ill patients who took imipenem/cilastatin.There were 14 patients in CRRT group and 19 in non-CRRT group.The dosage regimens were evaluated with 100%T MIC as the PK/PD target.RESULTS Calibration curves of imipenem showed a good linearity in the range of 0.5-50μg·mL^-1.The lower limit of quantification of imipenem was 0.5μg·mL^-1.Intra-and inter-day variations were all10%.The stability test showed that imipenem was stable during sample processing.At MIC2μg·mL^-1,the number of patients who met the criterion significantly reduced.CRRT-treated patients achieved a lower%TMIC than those who did not receive the therapy.CONCLUSION The method is simple,sensitive,accurate and fast,and is applicable to the guidance for individualized imipenem use in clinical practice.