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Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
Published on: August 30, 2018
Relationship between plasma polymyxin B concentrations and acute kidney injury in critically ill elderly patients:
Changyun Zhao1, Wenchao Mao1, Feifei Ye1
1Department of Critical Care Medicine, Zhejiang Hospital, Zhejiang, China.
Objective:
The objective of this study was to determine the relationship between the plasma polymyxin B concentration and renal function in elderly patients.
Methods:
This prospective, case-control, observational study included elderly patients who received polymyxin B therapy and were divided into an acute kidney injury (AKI) group and a non-AKI group based on their renal function. We monitored the pharmacokinetics and pharmacodynamics of polymyxin B, including the minimum plasma concentration (Cmin), mean blood drug concentration at steady state (Css,avg), and area under the concentration-time curve across 24 h at steady state (AUCss,24h) in both study groups. The plasma polymyxin concentration was determined using high-performance liquid chromatography-tandem mass spectrometry.
Results:
The loading doses, Cmin, Css,avg, and AUCss,24h were significantly higher in the AKI group than in the non-AKI group (p < 0.05). Receiver-operating characteristic curve analysis showed that the optimal cutoff values for predicting AKI were 2.94 mg/L for Cmin, 4.14 mg/L for Css,avg, and 99.35 mg·h/L for AUCss,24h, with corresponding sensitivities and specificities ranging from 78.57% to 82.14%.
Conclusion:
Monitoring plasma polymyxin B concentrations is essential in elderly patients. Keeping the Cmin below 2.94 mg/L, the Css,avg below 4.14 mg/L, and the AUCss,24h below 99.35 mg h/L may help prevent AKI in this population.
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