RESUMO
A prospective, randomized, double-blind comparison of cefazolin versus cefamandole was carried out to evaluate safety and efficacy and to determine bone and serum antibiotic concentrations in patients undergoing total joint arthroplasty. Dosages were 1 g of cefazolin before surgery followed by 500 mg every eight hours for six doses, versus 2 g of cefamandole before surgery followed by 1 g every eight hours for six doses. Intraoperative doses were given during prolonged procedures. No significant adverse drug reactions were clearly attributable to either drug. Among 48 patients receiving cefazolin there was one postoperative wound infection and one distant site infection. Among 49 patients receiving cefamandole, there were two postoperative wound infections and two distant site infections. No deep wound infections occurred in either group during at least 48 months of follow-up study. In hip specimens removed at surgery, the mean antibiotic concentrations were 1.6 +/- 1.4 micrograms/g for cefazolin recipients, compared with 5.7 +/- 5.9 micrograms/g for cefamandole recipients (p less than .001). In knee specimens, the mean antibiotic concentrations were 0.64 +/- 0.57 microgram/g for cefazolin recipients compared to 3.8 +/- 3.4 micrograms/g for cefamandole recipients (p = .004). Cefazolin given at one-half the dose of cefamandole appeared to be equally safe and effective but resulted in lower bone concentrations of antibiotic.