OBJECTIVETo determine the adequate timing of antibiotics application in severely burned patients by observing the dynamic changes of amikacin in blister fluid during early postburn stage.

METHODSTwenty patients in early stage of sever burns were divided into 4 groups (n=5) according to the timing of amikacin administration, namely at 3-4 h (group A), 10 h (group B, 20 h (group C), and 30 h (group D) postburn. Amikacin was administered intravenously via a single dose of 400 mg within 30 min, and at the time points of 0.25 to 7 h after completion of the infusion, the blister fluid was collected from each patient for determination of amikacin concentration with fluorescence polarization immunoassay.

RESULTSFifteen minutes after intravenous administration, amikacin could be detected in the blister fluid, reaching the highest level at 1-2 h after administration followed by gradual declination. In group B, blister fluid amikacin concentration reached 4.96+1.60 microg/ml 15 min after administration, and at the subsequent time points until 4 h, amikacin concentration was significantly higher in groups A and B than in groups C and D (P<0.05). Amikacin concentration in the blister fluid in group D was not sufficient for effective antibacterial therapy.

CONCLUSIONAmikacin administration in the early postburn stage may ensure higher amikacin concentration in the blister fluid and wound exudate. Better antibacterial effect can be expected when amikacin is applied within the initial 10 h postburn.