Studies of cefotaxime serum concentrations during surgery under general anaesthesia and its passage to the wound fluid after surgery for breast cancer.

We are reporting on a comparison of serum concentrations of cefotaxime during and after surgery and on its passage to the wound fluid after surgery. Five patients undergoing mastectomy and dissection of the axillary lymph nodes for breast cancer were studied. Serum concentrations were compared after 2 g of cefotaxime dissolved in 20 ml of saline had been administered by i.v. bolus injection intraoperatively during general anaesthesia and six to eight days postoperatively in a conscious state. After intraoperative administration under general anaesthesia, cefotaxime serum concentrations were 157.3 mg/l at 15 min, 87.5 mg/l at 30 min, 43.08 mg/l at 1 h, 15.54 mg/l at 2 h and 9.56 mg/l at 3 h. In a conscious state, cefotaxime serum concentrations were 122.0 mg/l at 15 min, 84.35 mg/l at 30 min, 47.63 mg/l at 1 h, 18.2 mg/l at 2 h and 9.63 mg/l at 3 h, comparable to the time course under general anaesthesia. The half-life of cefotaxime was 0.86 h under general anaesthesia and 0.92 h in a conscious state. Urinary recovery of cefotaxime (0 to 3 h) under anaesthesia and in a conscious state was 53.8% and 56.3%, respectively (as reported previously for a nonsurgical state). Samples of wound fluid were taken at the completion of surgery from the drain inserted subcutaneously into the wound or by means of a tracheal aspirator kit attached to a portable aspirator. Cefotaxime concentrations were determined postoperatively on days six to eight, when the wound fluid became no longer serous.(ABSTRACT TRUNCATED AT 250 WORDS)