Oral Postoperative Antibiotic Prophylaxis for Outpatient Total Hip and Knee Arthroplasty: Describing Current Practices.

ABSTRACT

BACKGROUND: Despite an increase in outpatient total hip arthroplasty (THA) and total knee arthroplasty (TKA), large-scale data are lacking on current practice for antibiotic prophylaxis prescribing. We aimed to describe current oral antibiotic prophylaxis practices nationally for outpatient THA and TKA. METHODS: This nationwide retrospective cohort study included primary outpatient THA or TKA procedures in patients aged 18 to 64 years from 2018 to 2021 using a national claims database. Oral antibiotic prescriptions filled perioperatively (defined as 5 days before to 3 days after surgery) were extracted; these were categorized and assumed to represent postoperative prophylaxis. Multivariable logistic regression measured associations between patient and surgery characteristics and perioperative oral antibiotic prophylaxis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) are reported. RESULTS: Oral antibiotic prescriptions were filled in 16.5% of 73,015 outpatient THA and TKA (18.4% of 24,857 THAs, 15.5% of 48,158 TKAs) procedures. Prescriptions were most often for cephalosporins (74.3%), with cephalexin (52.8%), and cefadroxil (19.1%) being the most common. Non-cephalosporin antibiotics prescribed were mainly clindamycin (6.8%), sulfamethoxazole-trimethoprim (6.7%), and doxycycline (6.2%). The odds of receiving oral antibiotic prophylaxis were higher for THA compared to TKA (OR 1.13, 95% CI 1.09 to 1.18, P < .001) and in the presence of obesity, diabetes, and autoimmune conditions (OR 1.08 to 1.13, P < .001 to .01). Ambulatory surgery center procedures also had significantly increased odds of prophylaxis compared to hospital-based outpatient surgeries (OR 2.62, 95% CI 2.51 to 2.73, P < .001). Additionally, regional and time-based variations were noted. CONCLUSIONS: Perioperative oral antibiotic prophylaxis prescriptions were filled in only 16.5% of outpatient THA and TKA cases, with variation in the type of antibiotic prescribed. The receipt of any prophylaxis and specific medications was associated with demographic, clinical, and procedure-related characteristics. Follow-up research will evaluate associations with infection risk reduction.