Even high-dose extended infusions may not yield desired concentrations of β-lactams: the value of therapeutic drug monitoring

Abstract

A 35-year-old patient in intensive care with severe burn injury developed episodes of sepsis. Blood culture yielded a multidrug-resistant Pseudomonas aeruginosa and treatment was commenced with amikacin (minimum inhibitory concentration (MIC) 2–4 mg/L, dose 20 mg/kg adjusted body weight 24-hourly) and meropenem (MIC 8 mg/L, dose 2 g IV 8-hourly and later 6-hourly). Despite the use of extended infusions with β-lactam therapeutic drug monitoring and doses that were more than 2.5 times higher than standard meropenem doses, resistance emerged. This case report describes the application of therapeutic drug monitoring to optimize β-lactam therapy in a difficult-to-treat critically ill patient.

Keywords::

• β-Lactams
• critically ill
• therapeutic drug monitoring
• extended infusions

Acknowledgments

J.A.R. received salary funding from the National Health and Medical Research Council of Australia, Career Development Fellowship, APP1048652.

Declaration of interest: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. The authors received no financial support for the research, authorship, and/or publication of this article.