Correlations between aminoglycoside pharmacokinetic parameters and patient's factors: from statement to implication for individual dosage design.

Amikacin pharmacokinetics was studied in 20 critically ill patients after a single i.v. bolus dose (500 mg). The amikacin pharmacokinetic profiles were characterized by marked intra-individual variability. Stepwise multivariate regression analysis made it possible to establish statistically significant correlations between the amikacin total clearance (Cl) and 8 patient's factors such as the, age, sodium plasma content, plasma osmolarity, partial pressure of oxygen and carbon dioxide, volumes of transfused plasma and blood, application of artificial lung ventilation (r2 = 0.98). The multiple regression equation for the Cl prediction provides reliable indirect estimation of the parameter. Thus, it appears possible to adjust the aminoglycoside dosage by taking into account 8 patient's factors, until the amikacin plasma concentration, time data are available.