Antibiotic dosing before primary hip and knee replacement as a pay-for-performance measure

Background: There is a trend toward linking the reimbursement for health care services to clinical outcome. One such pay-for-performance proposal that affects orthopaedic surgeons is linking reimbursement for hip and knee replacements to measures such as the percentage of patients receiving antibiotics before surgery. We analyzed the risk factors associated with failing to optimally administer preoperative antibiotics before primary hip and knee arthroplasty. Methods: Data on 988 elective primary total hip and knee replacements done at one institution were collected. Multivariate analysis was performed to determine clinical factors associated with administration of antibiotics outside the recommended window (within one hour before the incision). Results: Thirteen percent of the patients did not receive optimal antibiotic therapy (within the one-hour window prior to the elective arthroplasty). Five patients (0.5%) received no documented preoperative antibiotics. Patients undergoing total hip arthroplasty were more likely to receive antibiotics outside the one-hour window than were patients undergoing total knee arthroplasty. Longer induction times were associated with administration of antibiotics outside the one-hour window. Certain individual surgeons and anesthesiologists were more likely to administer antibiotics on time. The anesthesiologist effect was more significant than the surgeon effect. Conclusions: Approximately 13% of the patients did not receive optimal antibiotic therapy before total hip and knee replacement. Surgeons can improve their performance score for this measure by focusing antibiotic strategies on patients receiving a hip replacement and on complex cases, by developing systems for antibiotic dosing with the anesthesia team, and by improving documentation.