Local tissue concentrations of cefazolin during total joint arthroplasty: a systematic review

Preoperative, Intraoperative & Postoperative Concepts to Prevent Infection for Unicompartmental Knee Arthroplasty

Periprosthetic joint infection (PJI) is a complication that occurs in less than 1% of patients after unicompartmental knee arthroplasty (UKA). Though infrequent, it may potentially lead to revision while placing a significant financial burden on the healthcare system. Pre-operative, intra-operative, and postoperative strategies should be implemented to minimize the risk of PJI. Patient optimization prior to surgery can help to identify patients at risk for PJI and also maximize the health of the patient prior to surgery. Intraoperative and postoperative strategies can also mitigate the risk of postoperative infection. This article will summarize the evidence for preoperative, intra-operative, and postoperative strategies to prevent PJI in UKA. This will include topics on malnutrition and obesity, staphylococcus aureus, smoking, human immunodeficiency virus, rheumatoid arthritis, as well as skin preparation, laminar air flow, preoperative antibiotic administration anti-microbial incision drapes, pulsatile lavage, vancomycin powder, wound closure method, thromboprophylactic agents, and closed incisional negative pressure wound therapy dressings.

Tourniquet Use and Local Tissue Concentrations of Cefazolin During Total Knee Arthroplasty: A Randomized Clinical Trial

Importance

Prophylactic administration of antibiotics before skin incision is an important component in the prevention of periprosthetic joint infection in arthroplasty surgery. For antibiotics to be effective, the local tissue concentration (LTC) must exceed the minimum inhibitory concentration of typical infecting organisms; however, the LTC of cefazolin during arthroplasty is poorly understood.

Objective

To compare the systemic concentration of cefazolin in serum with the LTC in fat, synovium, and bone during primary total knee arthroplasty (TKA) while assessing the effect of tourniquet inflation.

Design, Setting, and Participants

This prospective randomized clinical trial was conducted from March 1, 2022, to June 30, 2023, in patients undergoing TKA at a single academic center.

Intervention

Total knee arthroplasty with or without a limb tourniquet.

Main Outcomes and Measures

Systemic blood and local tissues from the surgical site (fat, synovium, and bone) were harvested at regular intervals during the surgery. The primary outcome was the LTC of cefazolin, quantified using the liquid chromatography-tandem mass spectrometry technique.

Results

A total of 59 patients were included in the study, with 29 in the tourniquet group (mean [SD] age, 69.3 [9.6] years; 23 [79.3%] female) and 30 in the no tourniquet group (mean [SD] age, 69.9 [9.7] years; 21 [70.0%] female). In patients undergoing TKA without a tourniquet, the mean concentration of cefazolin in serum was 71.9 μg/mL (95% CI, 66.4-77.5 μg/mL), whereas the mean LTCs were 13.9 μg/g (95% CI, 12.1-15.7 μg/g) in fat, 27.7 μg/g (95% CI, 24.3-31.0 μg/g) in synovium, and 17.7 μg/g (95% CI, 14.8-20.5 μg/g) in bone. For patients undergoing TKA with a tourniquet, the mean concentration of cefazolin in serum was 72.0 μg/mL (95% CI, 66.3-77.7 μg/mL), and the mean LTCs were 9.9 μg/g (95% CI, 8.7-11.1 μg/g) in fat, 21.8 μg/g (95% CI, 18.7-25.0 μg/g) in synovium, and 13.0 μg/g (95% CI, 10.8-15.2 μg/g) in bone. The use of a tourniquet resulted in significantly lower mean LTCs by 60 minutes after cefazolin infusion (10.8 μg/g [95% CI, 9.1-12.4 μg/g] vs 16.9 μg/g [95% CI, 14.1-19.6 μg/g], P = .001 in fat; 18.9 μg/g [95% CI, 14.1-23.6 μg/g] vs 25.8 μg/g [95% CI, 21.4-30.3 μg/g], P = .03 in synovium; and 11.8 μg/g [95% CI, 9.3-14.2 μg/g] vs 19.4 μg/g [95% CI, 14.5-24.4 μg/g], P = .007 in bone).

Conclusions and Relevance

In this randomized clinical trial, the concentration of cefazolin was lower in local tissues (fat, synovium, and bone) than in systemic blood, and the use of a limb tourniquet further significantly reduced these concentrations. Although the current prophylactic dosing regimen for cefazolin provides sufficient serum concentrations, the levels in the periarticular tissue during TKA may be insufficient to prevent periprosthetic joint infection.

Trial Registration

ClinicalTrials.gov Identifier: NCT05604157.

Effective Antimicrobial Prophylaxis in Surgery: The Relevance and Role of Pharmacokinetics-Pharmacodynamics

Appropriate surgical antimicrobial prophylaxis (SAP) is an important measure in preventing surgical site infections (SSIs). Although antimicrobial pharmacokinetics-pharmacodynamics (PKPD) is integral to optimizing antibiotic dosing for the treatment of infections, there is less research on preventing infections postsurgery. Whereas clinical studies of SAP dose, preincision timing, and redosing are informative, it is difficult to isolate their effect on SSI outcomes. Antimicrobial PKPD aims to explain the complex relationship between antibiotic exposure during surgery and the subsequent development of SSI. It accounts for the many factors that influence the PKs and antibiotic concentrations in patients and considers the susceptibilities of bacteria most likely to contaminate the surgical site. This narrative review examines the relevance and role of PKPD in providing effective SAP. The dose-response relationship i.e., association between lower dose and SSI in cefazolin prophylaxis is discussed. A comprehensive review of the evidence for an antibiotic concentration-response (SSI) relationship in SAP is also presented. Finally, PKPD considerations for improving SAP are explored with a focus on cefazolin prophylaxis in adults and outstanding questions regarding its dose, preincision timing, and redosing during surgery.