Penetration of vancomycin into mediastinal and cardiac tissues in humans.

Vancomycin penetration into heart tissues (valves, myocardium, auricles, and pericardium) and mediastinal tissues (fat and sternal bone) was evaluated after two regimens of vancomycin administration. Ten patients were given 15 mg of vancomycin per kg of body weight before anesthesia. Ten other patients received the same dose and then a second 7.5-mg/kg dose at the time of initiation of cardiopulmonary bypass. Similar and satisfactory vancomycin tissue penetrations were observed in both groups. However, for some patients in the two groups, vancomycin levels in tissue were less than the MICs for potential pathogens (Staphylococcus aureus and Staphylococcus epidermidis).