厄他培南对院内生态环境影响.pptVIP

IVZ 2008-W-1259216-SS MS* As is the case with other β-lactam antibiotics, an important pharmacodynamic parameter that correlates well with clinical efficacy for carbapenems is the fraction of the dosing interval during which the drug concentration exceeds the MIC for a given pathogen. For bacteriostasis to occur, carbapenem concentrations must exceed the MIC for approximately 30% of the dosing interval (ie, approximately 8 hours for ertapenem).1 A pharmacokinetic study in 68 healthy adult subjects measured plasma concentrations of total and free (unbound) ertapenem following a single 1 g intravenous dose infused over 30 minutes.2 As shown on the slide, the MIC90 of Enterobacteriaceae was below the mean concentration of total ertapenem (red squares) for 24 hours postdose, and below the mean concentration of free ertapenem (gold squares) for at least 16 hours postdose. In addition, the MIC90 of P aeruginosa was below the mean concentration of total ertapenem (red squares) for at least 8 hours postdose.1,2 Thus, in this study, ertapenem demonstrated minimal potential for selection of resistant P aeruginosa and Enterobacteriaceae under clinical conditions. References Nix DE, Majumdar AK, DiNubile MJ. Pharmacokinetics and pharmacodynamics of ertapenem: an overview for clinicians. J Antimicrob Chemother. 2004;53(suppl S2):ii23–ii28. Friedland I, Mixson LA, Majumdar A, et al. In vitro activity of ertapenem against common clinical isolates in relation to human pharmacokinetics. J Chemother. 2002;14(5):483–491. 1/Nix, p ii27, Fig 4 (MICs) 2/Friedland, p 488, Fig 1 A (line graph) 1/Nix, p ii26, C2, ?4, L1-7 2/Friedland, p 488, Fig 1A + legend 1/Nix, p ii27, Fig 4 2/Friedland, p 488, Fig 1A NEW 对照研究—不同药物间比较 抗菌药物的消费量与耐药趋势的相关性研究 干预研究——限制相关抗菌药物 * * 研究结果可以看到哌拉西林/他唑巴坦组在治疗结束和治疗结束2周后患者肠道内的细菌监测发现其耐药菌株的比例菌比基线值高，在治疗后高达12.2%和在治疗两周后为4.5%。ESBL发生率则从基线的0.6%上升到治疗后的2.6%。而怡万之组，可以看到不论在治疗后还是治疗2周后耐药菌和ESBL发生率均没有明显改变。 这个研究发现怡万之在有效控制感染的同时对于耐药的筛选风险相当低。 Ref 1, p 4