[Study on cefotaxime in respiratory surgery: transfer to lung tissue and kinetics in serum]

Cefotaxime (CTX) was intravenously administered in a dose of 1 g to patients just prior to lung surgery. Lung tissue specimens were collected at 1, 2 and 3 hours after the CTX administration, and the concentration of CTX in each specimen was determined. At the same time, the concentration of CTX in the serum was also measured. The results are summarized below. 1. Determination of the CTX concentration in the lung tissue using bioassay showed values of 3.78 +/- 1.93 micrograms/g at 1 hour after CTX administration, 1.91 +/- 0.92 microgram/g at 2 hours, and 1.19 +/- 1.04 micrograms/g at 3 hours. 2. Determination of the CTX concentration in the serum using bioassay showed values of 36.9 +/- 14.4 micrograms/ml at 30 minutes after CTX administration, 22.5 +/- 10.5 micrograms/ml at 1 hour, 12.8 +/- 6.32 micrograms/ml at 2 hours, 8.52 +/- 5.54 micrograms/ml at 3 hours, and 3.98 +/- 3.19 micrograms/ml at 6 hours. The serum half-life was calculated to be 1.82 hours. 3. The CTX concentration of 3.78 +/- 1.93 micrograms/g in the lung tissue at 1 hour after CTX administration was more than 10 times higher than the MIC80 values for Streptococcus pneumoniae (MIC80 less than or equal to 0.025 microgram/ml) and Klebsiella pneumoniae (0.05 micrograms/ml), 2 of the principal causative organisms of respiratory tract infections. The pattern of change in concentrations of CTX in the serum of these surgical patients was concluded to be similar to the pattern in healthy adult subjects. On the basis of the results summarized above, it appears that CTX is a useful antimicrobial agent for application in the field of respiratory surgery.