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

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

Methods: 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.

Results: 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.

Conclusion: 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.