[Plasma and tissue concentrations of cefamandole during cardiac surgery]

This study aimed to determine plasma (CPC) and tissue concentrations of cefamandole during cardiac surgery, so as to compare them with the minimal inhibitory concentration (MIC) for staphylococci (0.25 - 1 microgram.ml-1 for S. aureus; 2 micrograms.ml-1 for S. epidermidis). Cefamandole was given prophylactically to 8 consecutive patients as a single intravenous dose of 60 mg.kg-1. Tissue concentrations were measured in presternal subcutaneous loose tissue and sternal marrow. Average CPC was 233.75 +/- 58 micrograms.ml-1, 15 min after drug administration, 187 +/- 6.4 micrograms.ml-1 at the time of sternotomy, 57.9 +/- 36.5 micrograms.ml-1 10 min after the start of bypass and 36.4 +/- 18.4 micrograms.ml-1 at its end, and 15.5 +/- 5.9 micrograms.ml-1 at the end of the procedure. Sternal subcutaneous tissue and marrow concentrations were respectively 24.4 +/- 13.3 micrograms.g-1 and 31 +/- 5.6 micrograms.g-1 at the time of sternotomy, and 9.4 +/- 5.5 micrograms.g-1 and 9.2 +/- 3.5 micrograms.g-1 at the end of the procedure. Giving a high dose of cefamandole preoperatively appeared to have an effective prophylactic antibiotic action, as the plasma and tissue concentrations were always higher than the MIC for staphylococci.