Jonathan R. Danoff

Introduction: Risk stratification is used in total joint arthroplasty (TKA) to optimize outcomes and minimize complications. Modifiable risk factors such as surgical duration can be influenced by surgeons; however, under certain circumstances, prolonged surgery cannot be avoided. While previous studies have investigated the impact of surgical duration on post-operative complications, we felt that research was lacking in comparing both surgical duration and tourniquet time and the rate of infection following a TKA. Our learning objective was to investigate the risk of surgical site infections (SSIs) and periprosthetic joint infections (PJIs) from prolonged (1) surgical duration or (2) tourniquet time during primary TKAs. Materials and Methods: A multicenter health-care system database consisting of 15 hospitals was queried for all patients undergoing TKA between March 2020 and December 2020. Patient demographics, comorbidities, and infection data were collected. The surgical duration and tourniquet time were calculated for each patient undergoing a TKA and compared against the rate of PJI or SSI rate. PJI was defined based on the 2018 musculoskeletal infection society (MSIS) criteria, and superficial SSI was defined as any infection that did not meet MSIS criteria. Results: Of the 2511 patients who underwent primary TKA, 19 were found to have an infection. Average surgical duration of 126.17 min for patients with an infection compared to 103.44 min without infection (P = 0.02). There was a significantly increased infection rate with increased surgical duration after univariate analysis. Patients who developed any infection had an average tourniquet time of 78.5 min, whereas those without infections had an average of 62.14 min (P = 0.004). Infection rate began to increase once the surgical duration reached 70 min; however, the infection rate increase per 10-min increments was not statistically significant (P = 0.09). The infection rate began to increase at 50 min of tourniquet time and significantly increased as tourniquet time increased (P = 0.004). Conclusion: Surgical duration is associated with an increased risk of infection following TKA. Our study demonstrated tourniquet time had a greater impact on infection. There are many circumstances that lead to increased surgical and tourniquet duration, including increased body mass index, and severe deformity. Surgeons should consider deflating the tourniquet as soon as the critical parts of the surgery are complete to decrease the risk of post-operative infections. Keywords: Total knee replacement, infection, knee joint, tourniquets.

Background: Since the 2003 NIH consensus statement, the use of prophylactic antibiotics in total knee arthroplasty (TKA) has been the standard of care. Some studies recommend antibiotic administration within 1 h of skin incision, but no specific time frame has been delineated. The objective of this study was to determine if timing of pre-operative antibiotics is associated with post-operative infection after TKA. Materials and Methods: An institutional database from a multi-center health-care system was queried with ICD-10 codes and reviewed for patients undergoing primary TKA between March 2020 and December 2020. The rate of superficial surgical site infection (SSI) and periprosthetic joint infection (PJI) was compared with pre-operative antibiotic timing. PJIs were defined based on 2018 MSIS criteria and superficial SSIs were other infections that did not meet MSIS criteria. Antibiotic timing was separated into 15-min cohorts from 0 min before skin incision to over 45 min before incision. Further comparison between patients who received antibiotics within 30 min of incision with those who received antibiotics greater than 30 min prior was performed. Results: Of the 2511 patients who underwent primary TKA, 19 were found to have post-operative infections. There were 7 SSIs, and 12 PJIs, 16 of the post-operative infections occurred when patients received antibiotics <30 min before incision. There was no significant difference in SSIs or PJIs between each 15-min time interval of antibiotic administration (P = 0.45) or between the 30-min time intervals (P = 0.09). Conclusion: Our study demonstrates no difference in post-operative infection based on pre-operative antibiotic timing. As long as antibiotics are given within 60 min of incision, preferentially 30–60 min before incision, their timing does not have a significant effect on post-operative infection following TKA. Keywords: Pre-operative antibiotics, periprosthetic joint infection, superficial skin infection, total knee arthroplasty, complications

INTRODUCTION: Despite advancements in the field of adult reconstruction, prosthetic joint infection (PJI) remains a common and devastating complication of total joint arthroplasty. Eradication of these infections can often prove difficult, and they remain a source of considerable morbidity and mortality. This clinical review paper will focus on some of the more commonly used irrigation solutions; povidone-iodine (PI), chlorhexidine (CHG), acetic acid (AA), hydrogen peroxide (HP), antibiotic irrigations, taurolidine, and polyhexanide-betaine (PB) SUMMARY OF THE EVIDENCE: Significant research has been performed on the prevention of PJI, including use of intraoperative joint irrigation solutions. Several solutions have been theorized to aid in infection prevention, but no evidence-based practice guidelines in this area of orthopaedics have been established. There is a paucity of prospective randomized control trials to compare the efficacy of these joint irrigation solutions. CONCLUSIONS: The authors present a review regarding seven major categories of commonly used intraoperative joint irrigation solutions. The current literature fails to demonstrate a clear consensus for a preferred solution and concentration for povidone-iodine, chlorhexidine, hydrogen peroxide, acetic acid, antibiotic irrigations, taurolidine, and polyhexanide-betaine. Prospective, randomized control trials directly comparing these different irrigation solutions are needed.