[Pharmacokinetics changes of amikacin in severe burn patients at early stage]

To investigate the concentration and pharmacokinetics changes of amikacin in the serum and blister fluid in severe burn patients at early stage.

Twenty severe burn patients during early postburn stage were divided into four groups with five patients in each group. Each patient was given a single dose of 400 mg amikacin in 30 minutes during 3-4 postburn hour (PBH) in A group, at 10 PBH in B group, at 20 PBH in C group, and at 30 PBH in D group. The concentration of amikacin in blister fluid was examined at 0.25, 0.5 min and 1, 2, 3, 4, 5, 6, 7 h after treatment by fluorescence polarization immunoassay, meanwhile, the venous blood of 9 patients among them was also collected to determine the concentration of amikacin at the same time points. Pharmacokinetics parameters of model were produced by program 3P97.

Among all groups, the concentration of amikacin in blister fluid in A group increased quickest and maintained longest, that of B group ranked second. The amikacin concentration of blister fluid in A, B groups were obviously higher than those in C, D groups at each time point (P <0.05 orP < 0.01), especially at 1PBH (12.53 +/- 1.76, 9.52 +/- 1.51 microg/mL vs 4.65 +/- 0.77, 3.10 +/- 0.41 microg/ml, P < 0.01). The serum concentration of amikacin in 9 patients were decreasing along with elapse of time. The amikacin concentration-time curves in blister fluid and serum were best fit in two compartment models. Compared with that in normal value, t1/2beta of amikacin from burn patient was shortened in serum and prolonged in blister fluid.

Early administration of amikacin in burn patients (within 10 PBH) may form an effective and continuous antibiotics barrier around the wound to prevent bacterial infection.