Effect of analytical inaccuracy on dose adjustment for vancomycin,amikacin, and tobramycin using the Abbottbase Pharmacokinetic Systems

The authors studied the inaccuracy effect in the determination of C(min) and C(1h) post-infusion serum concentrations of vancomycin, amikacin, and tobramycin on the recommended dose regimen (RDR) using the Abbottbase Pharmacokinetic Systems (PKS) program (Abbott; Abbott Park, IL). According to previously established criteria, the clinically acceptable error (CAE) was defined as 1/8 of the therapeutic range. For a total of 647 simulations, in most cases (94.3%) an inaccuracy of up to three times the CAE did not lead to changes in the RDR. However, and particularly for amikacin and tobramycin, in some cases an inaccuracy in the order of the CAE in C(min) lead to important differences in the RDR, which could have important consequences in clinical practice. For therapeutic monitoring of these antibiotics, it is suggested that a serum concentration from a previous moment in time, which may be determined with greater precision and accuracy, could be used instead of C(min).