Abstract
Since beta-lactam antibiotics have concentration-independent killing, bacterial eradication is a function of the time the serum drug concentration remains above the drug's MIC (T > MIC). We compared the serum bactericidal titers (SBTs) of ceftazidime given by continuous infusion (CI) or by intermittent bolus dosing (BD) against two clinical isolates each of Pseudomonas aeruginosa and Escherichia coli to determine if CI would allow lower daily dosing while still providing equal bactericidal activity compared with BD. This was an open-labeled, randomized, steady-state, four-way crossover study with 12 healthy volunteers. The ceftazidime regimens were 1 g every 8 h (q8h) BD, 1 g q12h BD, 3 g over 24 h CI, and 2 g over 24 h CI. The areas under the bactericidal curves were calculated by the trapezoidal rule using the reciprocal of the SBT. For all organisms the areas under the bactericidal curves for intermittent versus the CI regimens were the same for equal doses (P > 0.05). For both strains of E. coli all four regimens provided SBTs of > or = 1:2 over the dosing interval and 100% T > MIC. The 1-g q8h BD and q12h BD regimens provided T > MIC of 82 and 52%, respectively, for both P. aeruginosa isolates (MICs, 4 micrograms/ml). In comparison, the 2- and 3-g CI regimens always maintained SBTs of > or = 1:2 and T > MIC over the 24-h period as serum drug concentrations were 12.8 +/- 3.0 and 18.2 +/- 4.5 micrograms/ml, respectively. CI optimizes the pharmacodynamic and pharmacoeconomic profile of ceftazidime by providing adequate antibacterial activity over the 24-h dosing period with a reduction in the total daily dose of the antimicrobial agent.
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Selected References
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- Barriere S. L., Ely E., Kapusnik J. E., Gambertoglio J. G. Analysis of a new method for assessing activity of combinations of antimicrobials: area under the bactericidal activity curve. J Antimicrob Chemother. 1985 Jul;16(1):49–59. doi: 10.1093/jac/16.1.49. [DOI] [PubMed] [Google Scholar]
- Bodey G. P., Ketchel S. J., Rodriguez V. A randomized study of carbenicillin plus cefamandole or tobramycin in the treatment of febrile episodes in cancer patients. Am J Med. 1979 Oct;67(4):608–616. doi: 10.1016/0002-9343(79)90242-0. [DOI] [PubMed] [Google Scholar]
- Craig W. A., Ebert S. C. Continuous infusion of beta-lactam antibiotics. Antimicrob Agents Chemother. 1992 Dec;36(12):2577–2583. doi: 10.1128/aac.36.12.2577. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ebert S. C., Craig W. A. Pharmacodynamic properties of antibiotics: application to drug monitoring and dosage regimen design. Infect Control Hosp Epidemiol. 1990 Jun;11(6):319–326. doi: 10.1086/646178. [DOI] [PubMed] [Google Scholar]
- Kalman D., Barriere S. L., Johnson B. L., Jr Pharmacokinetic disposition and bactericidal activities of cefepime, ceftazidime, and cefoperazone in serum and blister fluid. Antimicrob Agents Chemother. 1992 Feb;36(2):453–457. doi: 10.1128/aac.36.2.453. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Livingston D. H., Wang M. T. Continuous infusion of cefazolin is superior to intermittent dosing in decreasing infection after hemorrhagic shock. Am J Surg. 1993 Feb;165(2):203–207. doi: 10.1016/s0002-9610(05)80507-0. [DOI] [PubMed] [Google Scholar]
- Mordenti J. J., Quintiliani R., Nightingale C. H. Combination antibiotic therapy: comparison of constant infusion and intermittent bolus dosing in an experimental animal model. J Antimicrob Chemother. 1985 Jan;15 (Suppl A):313–321. doi: 10.1093/jac/15.suppl_a.313. [DOI] [PubMed] [Google Scholar]
- Mouton J. W., Horrevorts A. M., Mulder P. G., Prens E. P., Michel M. F. Pharmacokinetics of ceftazidime in serum and suction blister fluid during continuous and intermittent infusions in healthy volunteers. Antimicrob Agents Chemother. 1990 Dec;34(12):2307–2311. doi: 10.1128/aac.34.12.2307. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mouton J. W., den Hollander J. G. Killing of Pseudomonas aeruginosa during continuous and intermittent infusion of ceftazidime in an in vitro pharmacokinetic model. Antimicrob Agents Chemother. 1994 May;38(5):931–936. doi: 10.1128/aac.38.5.931. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nicolau D. P., Quintiliani R. Choosing between the new cephalosporin antibiotics: a pharmacodynamic approach. Pharmacoeconomics. 1994;5(Suppl 2):34–39. doi: 10.2165/00019053-199400052-00007. [DOI] [PubMed] [Google Scholar]
- Nicolau D., Quintiliani R., Nightingale C. H. Once-daily aminoglycosides. Conn Med. 1992 Oct;56(10):561–563. [PubMed] [Google Scholar]
- Nightingale C. H., Quintiliani R., Nicolau D. P. Intelligent dosing of antimicrobials. Curr Clin Top Infect Dis. 1994;14:252–265. [PubMed] [Google Scholar]
- Onyeji C. O., Nicolau D. P., Nightingale C. H., Quintiliani R. Optimal times above MICs of ceftibuten and cefaclor in experimental intra-abdominal infections. Antimicrob Agents Chemother. 1994 May;38(5):1112–1117. doi: 10.1128/aac.38.5.1112. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peterson L. R., Gerding D. N., Fasching C. E. Effects of method of antibiotic administration on extravascular penetration: cross-over study of cefazolin given by intermittent injection or constant infusion. J Antimicrob Chemother. 1981 Jan;7(1):71–79. doi: 10.1093/jac/7.1.71. [DOI] [PubMed] [Google Scholar]
- Reller L. B., Stratton C. W. Serum dilution test for bactericidal activity. II. Standardization and correlation with antimicrobial assays and susceptibility tests. J Infect Dis. 1977 Aug;136(2):196–204. doi: 10.1093/infdis/136.2.196. [DOI] [PubMed] [Google Scholar]
- Roosendaal R., Bakker-Woudenberg I. A., van den Berg J. C., Michel M. F. Therapeutic efficacy of continuous versus intermittent administration of ceftazidime in an experimental Klebsiella pneumoniae pneumonia in rats. J Infect Dis. 1985 Aug;152(2):373–378. doi: 10.1093/infdis/152.2.373. [DOI] [PubMed] [Google Scholar]
- Vogelman B., Gudmundsson S., Leggett J., Turnidge J., Ebert S., Craig W. A. Correlation of antimicrobial pharmacokinetic parameters with therapeutic efficacy in an animal model. J Infect Dis. 1988 Oct;158(4):831–847. doi: 10.1093/infdis/158.4.831. [DOI] [PubMed] [Google Scholar]