title: Development and Assessment of a Nomogram to Propose the Initial Dosage Regimen of a Meropenem Infusion Based on Serum Creatinine and Age Using a Monte Carlo Simulation.
abstract: A conventional nomogram, based on serum creatinine (sCr) and age, was developed in order to determine the correct initial dosage regimen for meropenem (MEPM) infusions in elderly patients with severe community-acquired pneumonia (CAP), using a target minimum inhibitory concentration (MIC) of 2 mg/L. A correlation between age and actual bodyweight (BW) in a development cohort of 44 males and 45 females was performed by linear regression using the least-squares method (male: y=-0.4676x+80.281, R(2)=0.4888; female: y=-0.4373x+77.502, R(2)=0.3194). There were no significant differences between actual BW and the BW (e-BW) estimated using this equation in this cohort (male: e-BW 41.6±3.1 kg, BW 41.7±3.5 kg, p=0.93; female: e-BW 39.5±2.1 kg, BW 39.5±3.7 kg, p=0.20). By integrating these equations using the Monte Carlo simulation method, a dosage regime was calculated which would have an 80% probability of maintaining plasma drug levels above the MIC for more than 40% of the time (>40%TAM), using only the age and sCr of individual patients. This relationship was summarized as a nomogram. The nomogram was validated using an independent validation cohort (n=28) of patients. An optimized dosage regimen could be predicted in 84 patients (94.4%) in the development cohort and 25 patients (89.3%) in the validation cohort. This nomogram may be a useful tool for clinicians and pharmacists in determining an initial MEPM regimen in elderly patients with severe CAP, based only on age and sCr.
authors.affiliation: Pharmacy of Saiseikai Chuwa Hospital.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Shino
authors.forename: Takahiro
authors.initials: T
authors.lastname: Uchida
authors.forename: Miyako
authors.initials: M
authors.lastname: Yoshida
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nomura
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use; D001835:Body Weight; D017714:Community-Acquired Infections / Q000097:blood / Q000188:drug therapy; D003404:Creatinine / Q000097:blood*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D016014:Linear Models; D008297:Male; D000077731:Meropenem; D009010:Monte Carlo Method; D049451:Nomograms; D013845:Thienamycins / Q000008:administration & dosage* / Q000097:blood* / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D003404:Creatinine; D000077731:Meropenem