The Mark Coventry Award: Higher tissue concentrations of vancomycin with low-dose intraosseous regional versus systemic prophylaxis in TKA: a randomized trial

Low Risk of Periprosthetic Joint Infection After Aseptic Revision Total Knee Arthroplasty with Intraosseous Vancomycin

BACKGROUND

Aseptic revisions are the most common reason for revision total knee arthroplasty (rTKA). Previous literature reports early periprosthetic joint infection (PJI) rates after aseptic rTKA to range from 3 to 9.4%. Intraosseous regional administration (IORA) of vancomycin has previously been shown to produce high local tissue concentrations in primary and revision TKA. However, no data exists on the effect of prophylactic intraosseous (IO) vancomycin on early PJI rates in the setting of aseptic rTKA. The aim of this study was to determine: (1) what is the rate of early PJI during the first year after surgery in aseptic rTKA performed with IO vancomycin; and (2) how does this compare to previously published PJI rates after rTKA.

METHODS

A consecutive series of 117 cases were included in this study who underwent rTKA between January 2016 and March 2022 by one of two fellowship-trained adult reconstruction surgeons and received IO vancomycin at the time of surgery in addition to standard intravenous (IV) antibiotic prophylaxis. Rates of PJI at 3 months, 1 year, and final follow-up were evaluated and compared to prior literature.

RESULTS

Follow-up at three months was available for 116 of the 117 rTKAs, with one lost to follow-up. The rate of PJI was 0% at three months postoperatively. Follow-up at one year was obtained for 113 of the 117 rTKAs, and the PJI rate remained 0%. The rate of PJI at final follow-up of ≥ 1 year was 0.88% (95% CI [confidence interval], -0.84 to 2.61). Previous literature reports PJI rates in aseptic R-TKA to range from 3 to 9.4%.

CONCLUSIONS

Dual prophylactic antibiotics with IO vancomycin in conjunction with IV cephalosporins or clindamycin were associated with a substantial reduction in early PJI compared to prior published literature. This data supplements the early evidence about the potential clinical benefits of IO vancomycin for infection prevention in high-risk cases.

[Intraosseous vancomycin in total knee arthroplasty]

INTRODUCTION

intravenous antibiotic prophylaxis has significantly reduced the incidence of periprosthetic joint infection (PJI) in knee surgeries. However, for patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) or those at risk of colonization, prophylaxis should include vancomycin. Intraosseous (IO) administration of vancomycin could enhance its effectiveness in total knee arthroplasty (TKA).

MATERIAL AND METHODS

a retrospective review was conducted, including 143 patients at risk of PJI scheduled for TKA who received IO vancomycin along with intravenous (IV) cefazolin, referred to as group I (GI), between May 2021 and December 2022. The occurrence of complications in the first three postoperative months was evaluated. Results were compared with 140 patients without risk factors who received standard IV prophylaxis, designated as group II (GII).

RESULTS

in GI, 500 mg of IO vancomycin was administered, injected into the proximal tibia, in addition to standard IV prophylaxis. In GII, patients received only IV cefazolin. The incidence of complications was 1.64% in GI and 1.4% in GII. The PJI rate at 90 postoperative days was 0.69% in GI and 0.71% in GII.

CONCLUSIONS

IO vancomycin administration, along with standard IV prophylaxis, provides a safe and effective alternative for patients at risk of MRSA colonization. This approach minimizes complications associated with IV vancomycin use and addresses logistical challenges of timely administration.

Intraosseous Administration of Medications in Total Knee Arthroplasty: An Opportunity for Improved Outcomes and Superior Compliance

Background

Vancomycin is a prophylactic antibiotic with bactericidal activity against methicillin-resistant Staphylococcus aureus that is commonly used in total joint replacement surgery1. In total knee arthroplasty (TKA), intraosseous infusions administered following tourniquet inflation have demonstrated improved local vancomycin concentrations with decreased systemic absorption1-3. This administration method results in no adverse reactions locally, as well as equivalent or lower systemic complications compared with other vancomycin administration methods4. Intraosseous infusion of prophylactic surgical antibiotics has been shown to be more effective than intravenous administration, with the potential for reduction in surgical site infections5.

Description

After the operative extremity has been prepared and draped in the usual sterile fashion, the limb is elevated and the tourniquet is inflated to 250 mm Hg. Prior to incision, an intraosseous vascular access system (Arrow EZ IO; Teleflex) is inserted with a power driver into the tibial tubercle region. The desired volume of the medication is injected into the tibia. The device is removed and then inserted into the anterior distal femur, centrally, just proximal to the patella. Following this, the desired volume of the medication is injected into the femur. The device is then removed, and the TKA proceeds according to the surgeon's standard technique.

Alternatives

Alternative administration methods for vancomycin include other invasive methods and noninvasive delivery. Intravenous delivery is the most traditional form of medication delivery1,2. Additional alternatives include noninvasive placement of antibiotic powder into the wound and localized soft-tissue injections of desired medications1-3.

Rationale

Opting to administer antibiotics and other medications intraosseously (rather than intravenously) has shown improved compliance with the golden-hour rule of preoperative antibiotics (especially for vancomycin)4, lower incidences of acute kidney injury or adverse systemic effects4, and improved local tissue concentrations of all medications delivered1-3.

Expected Outcomes

Expected outcomes include improved local tissue concentrations with decreased systemic concentrations of vancomycin and with no reported local or systemic adverse reactions, as well as the potential for improved infection prevention1-5. Literature regarding the use of intraosseous infusion during TKA has been thorough and very well received. A prospective, randomized study by Young et al. evaluated local and systemic concentrations of vancomycin following intraosseous versus intravenous administration. The authors found that low-dose intraosseous vancomycin resulted in tissue concentrations equal to or superior to those of systemic administration, also noting that the administration route reduced the infiltration time of the vancomycin without systemic complications1. Local concentrations at the knee were found to be 5 to 9 times greater with intraosseous infusion in patients with a body mass index of >35 kg/m2 as compared with the use of intravenous administration, with no adverse reactions systemically. Local concentrations in this patient population were also found to be comparable to those observed in patients with a lower body mass index2. A recent study assessing the use of intraosseous vancomycin showed that local concentrations of vancomycin were maintained even if the procedure continued beyond the point of tourniquet deflation, with mean concentrations being 5 times higher locally at the end of the procedure in the intraosseous versus the intravenous group3. A separate study showed no adverse systemic reactions and no incidents of acute kidney injury among patients receiving intraosseous vancomycin. An additional study showed that intraosseous administration of vancomycin decreased the incidence of postoperative joint infections compared with traditional intravenous administration5. Newer studies assessing the use of intraosseous infiltration have begun to focus on the delivery of other medications, not just antibiotics. At our institution, we have examined the benefits of intraosseously administrated morphine, which has shown a significant decrease in pain and opioid consumption up to 2 weeks postoperatively.

Important Tips

You may run into issues with the medication delivery due to the amount of resistance you encounter. If resistance is too great, you may first attempt to readjust the intraosseous needle depth to improve flow. If resistance is still high, you may consider downsizing to a 30-cc syringe in order to better infiltrate the medication.Note that if you downsize your syringe, you will require more time to infiltrate the desired amount of fluid. An additional way to save time is to open multiple syringes and have them prefilled with your desired medication so that they may be handed off once completed rather than needing to be refilled.A hemostat or pickup may be applied underneath the cuff of the intraosseous needle in order to help remove the needle from the bone. This step is sometimes required because the intraosseous handpieces do not have multidirectional trigger capabilities, and removing the needle can require an upward force to be applied.The use of midline locations allows the small incisions you make for intraosseous infusion to be incorporated into your larger knee incision, with no additional morbidity to the patient.Consider utilizing the medial and/or lateral femoral condyles as landmark locations for infusion if your patient is large. Alternatively, recent literature has shown nearly equivalent results with just the tibial infusion, so you may consider discontinuing the femoral intraosseous infusion if there are consistent issues with successfully initiating the medication delivery.

Acronyms and Abbreviations

IO = intraosseousMRSA = methicillin-resistant Staphylococcus aureusRCT = randomized controlled trialsIV = intravenousBMI = body mass indexOR = operating room.

Intraosseous Versus Intravenous Vancomycin in Tourniquetless Primary Total Knee Arthroplasty: A Randomized Trial

INTRODUCTION

Intraosseous (IO) administration of vancomycin at the time of total knee arthroplasty (TKA) has been shown to be safer and more effective than intravenous (IV) administration at preventing early periprosthetic joint infection. Previous studies have relied on tourniquet inflation to enhance local tissue concentrations and mitigate systemic release.

METHODS

A single-blinded, randomized clinical trial was performed on 20 patients (10 IV, 10 IO) undergoing primary TKA. The control (IV) group received weight-dosed vancomycin approximately 1 hour prior to the incision and weight-dosed cefazolin immediately prior to the incision. The interventional (IO) group received weight-dosed cefazolin immediately prior to the incision and 500 mg of vancomycin delivered via the IO technique at the time of the incision. Systemic samples for vancomycin levels were taken prior to the incision and at closure. During the procedure, tissue samples were taken from the distal femur, proximal tibia, and suprapatellar synovium. There were no differences in patient demographics or changes in serum creatinine from preoperative to postoperatively between groups.

RESULTS

Significant differences in systemic vancomycin levels (ug/mL) were found at the start of the case (IV = 27.9 ± 4.9 versus IO = 0 ± 0, P = 0.0004) and at the end of the case (IV = 19.6 ± 2.6 versus IO = 7.8 ± 1.0, P = 0.001). No significant differences were seen in the average vancomycin concentration in the distal femur (IV = 61.0 ± 16.0 versus IO = 66.2 ± 12.3, P = 0.80), proximal tibia (IV = 52.8 ± 13.5 versus IO = 57.1 ± 17.0, P = 0.84), or suprapatellar synovial tissue (IV = 10.7 ± 5.3 versus IO = 9.0 ± 3.3, P = 0.80). There were no complications associated with vancomycin administration in either group.

CONCLUSION

This study demonstrates the utility of IO vancomycin in tourniquetless TKA with similar local tissue and significantly lower systemic concentrations than IV administration.

Prolonged efficacy of cefazolin in intraosseous regional prophylaxis for total knee arthroplasty: a rabbit model study

BACKGROUND

A novel approach known as intraosseous regional administration (IORA) has emerged as a technique for delivering prophylactic antibiotics, and it results in higher tissue concentrations around the knee. It is hypothesized that IORA of cefazolin for antibiotic prophylaxis during total knee arthroplasty will result in sustained effective levels for a longer duration. The aim of the current study was to investigate temporal changes in peri-knee cefazolin blood concentrations after IORA of cefazolin.

METHODS

Twelve rabbits were randomly divided into two groups, with six rabbits in each group. In control group a single intravenous bolus injection of cefazolin (10 mL, 100 mg) was administered into the marginal ear vein. In experimental groupexperimental group the same dose of cefazolin was injected into the left tibial marrow cavity after tourniquet inflation at the base of the left thigh. Blood samples were collected periodically at different timepoints, and cefazolin concentrations were determined.

RESULTS

The intraosseous treatment resulted in significant differences in plasma cefazolin concentrations at all timepoints. Experimental group exhibited higher plasma cefazolin concentrations than control group.

CONCLUSIONS

Cefazolin in intraosseous regional prophylaxis exhibits effectiveness in intraoperative antibiotic prophylaxis by maintaining concentrations above the minimum inhibitory concentration for extended durations, rather than relying solely on high concentrations.

Intraosseous regional prophylaxis in total knee arthroplasty

Prophylactic antibiotics are important in reducing the risk of periprosthetic joint infection (PJI) following total knee arthroplasty. Their effectiveness depends on the choice of antibiotic and the optimum timing of their administration, to ensure adequate tissue concentrations. Cephalosporins are typically used, but an increasing number of resistant organisms are causing PJI, leading to the additional use of vancomycin. There are difficulties, however, with the systemic administration of vancomycin including its optimal timing, due to the need for prolonged administration, and potential adverse reactions. Intraosseous regional administration distal to a tourniquet is an alternative and attractive mode of delivery due to the ease of obtaining intraosseous access. Many authors have reported the effectiveness of intraosseous prophylaxis in achieving higher concentrations of antibiotic in the tissues compared with intravenous administration, providing equal or enhanced prophylaxis while minimizing adverse effects. This annotation describes the technique of intraosseous administration of antibiotics and summarizes the relevant clinical literature to date.

Higher cefazolin concentrations in synovial fluid with intraosseous regional prophylaxis in knee arthroplasty: a randomized controlled trial

BACKGROUND

Prophylactic antibiotics reduce the risk of periprosthetic joint infection. However, conventional systemic administration may not provide adequate tissue concentrations against more resistant organisms such as coagulase-negative staphylococci. Intraosseous regional administration is known to achieve significantly higher antibiotic tissue concentrations than systemic administration, but it is unclear how synovial fluid concentrations are affected. We aimed to compare synovial fluid cefazolin concentrations achieved by regional intraosseous versus systemic intravenous administration, and also to compare synovial fluid cefazolin concentrations with those in subcutaneous fat.

METHODS

A total of 60 patients undergoing primary knee arthroplasty were randomized into 2 groups: group IO received 2 g interosseous cefazolin in 100 mL saline through a tibial cannula after tourniquet inflation and before skin incision; group IV received 2 g cefazolin in 100 mL saline via the median basilic or median cephalic vein 30 min before tourniquet inflation. Subcutaneous fat and synovial fluid samples were collected immediately after skin incision, and cefazolin concentrations were measured by high-performance liquid chromatography.

RESULTS

The cefazolin concentration in synovial fluid was 391.3 ± 70.1 μg/ml in group IO and 17.6 ± 3.5 μg/ml in group IV. The cefazolin concentration in subcutaneous fat was 247.9 ± 64.9 μg/g in group IO and 11.4 ± 1.9 μg/g in group IV.

CONCLUSION

Intraosseous regional administration results in several times higher tissue concentrations than systemic administration, especially in the synovial fluid.

Intraosseous Vancomycin in Total Hip Arthroplasty - Superior Tissue Concentrations and Improved Efficiency

BACKGROUND

Literature shows that intraosseous (IO) infusions are capable of providing increased local concentrations compared to those administered via intravenous (IV) access. Successes while using the technique for antibiotic prophylaxis administration in total knee arthroplasty (TKA) prompted consideration for use in total hip arthroplasty (THA) however; no study exists for the use of IO vancomycin in THA.

METHODS

This single-blinded randomized control trial was performed from December 2020 to May 2022. Twenty patients were randomized into one of two groups: IV vancomycin (15 mg/kg) given routinely, or IO vancomycin (500mg/100cc of NS) injected into the greater trochanter during incision. Serum vancomycin levels were collected at incision and closure. Soft tissue vancomycin levels were taken from the gluteus maximus (at start and end of case), and acetabular pulvinar tissue. Bone vancomycin levels were taken from the femoral head, acetabular reamings, and intramedullary bone. Adverse local/systemic reactions, 30-day and 90-day complications were also tracked.

RESULTS

A statistically significant reduction in serum vancomycin levels was seen when comparing IO to IV vancomycin at both the start and end of the procedure. All local tissue samples had higher concentrations of vancomycin in the IO group. Statistically significant increases were present within the acetabular bone reamings, and approached significance in intramedullary femoral bone.

CONCLUSION

This study demonstrates the utility of IO vancomycin in primary THA with increased local tissue and decreased systemic concentrations. With positive findings in an area without tourniquet use, IO may be considered for antibiotic delivery for alternative procedures.

Principles of mechanical and chemical debridement with implant retention

BACKGROUND

Periprosthetic joint infection (PJI) is one of the most common causes of early revision for total hip and knee arthroplasty. Mechanical and chemical debridement typically referred to as debridement, antibiotics, and implant retention (DAIR) can be a successful technique to eradicate PJI in acute postoperative or acute hematogenous infections. This review will focus specifically on the indications, techniques, and outcomes of DAIR.

DISCUSSION

The success of mechanical and chemical debridement, or a DAIR operation, is reliant on a combination of appropriate patient selection and meticulous technique. There are many technical considerations to take into consideration. One of the most important factors in the success of the DAIR procedure is the adequacy of mechanical debridement. Techniques are surgeon-specific and perhaps contribute to the large variability in the literature on the success of DAIR. Factors that have been shown to be associated with success include the exchange of modular components, performing the procedure within seven days or less of symptom onset, and possibly adjunctive rifampin or fluoroquinolone therapy, though this remains controversial. Factors that have been associated with failure include rheumatoid arthritis, age greater than 80 years, male sex, chronic renal failure, liver cirrhosis, and chronic obstructive pulmonary disease.

CONCLUSIONS

DAIR is an effective treatment option for the management of an acute postoperative or hematogenous PJI in the appropriately selected patient with well-fixed implants.

Intraosseous Regional Administration of Antibiotic Prophylaxis for Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Intraosseous regional administration (IORA) of antibiotics after tourniquet inflation has recently been introduced as a technique to deliver antibiotics directly to the surgical site among patients undergoing total knee arthroplasty (TKA).

METHODS

PubMed and Embase were queried for studies reporting on IORA for perioperative prophylaxis during TKA. Primary outcome measures were local tissue antibiotic concentrations and rates of prosthetic joint infection (PJI). Eight studies were included for analysis. Four studies (all randomized controlled trials) compared local tissue concentrations between patients receiving IORA and intravenous (IV) antibiotics. Six studies assessed the rate of PJI among patients receiving IORA versus IV antibiotics.

RESULTS

All studies found a statistically significant increase in antibiotic concentration in femoral bone and fat samples in patients who were treated with IORA (44.04 μg/g [fat] and 49.3 μg/g [bone] following 500 mg of intraosseous vancomycin) versus IV (3.5 μg/g [fat] and 5.2 μg/g [bone] following 1 g IV of vancomycin). The two studies powered to determine differences in PJI rates found a statistically significant decrease in the rate of PJI among patients receiving IORA versus IV antibiotics. The incidence of PJI in patients treated with IORA and IV antibiotics across all studies was 0.3 and 1.1%, respectively.

CONCLUSION

Perioperative IORA of antibiotics in TKA provides local tissue concentrations of antibiotics that are on average 10 times higher than IV administration alone. Although more adequately powered investigations are necessary to determine the effectiveness of IORA in reducing PJI rates, adoption of IORA should be considered in high-risk patients where elevated tissue antibiotic concentrations would be of a maximum benefit.

Intraosseous regional prophylactic antibiotics decrease the risk of infection in total knee arthroplasty compared with intravenous antibiotics: a systematic review and meta-analysis

Purpose

Surgical site infection (SSI) is a rare and serious complication of total knee arthroplasty (TKA), which causes a poor prognosis for patients. The purpose of this study was to explore the effect of intraosseous (IO) antibiotics in preventing infection and complications after TKA compared with intravenous (IV) antibiotics and to provide a certain theoretical basis for clinical treatment.

Methods

The review process was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the PubMed, Embase, Ovid, Web of Science, and the Cochrane Central Register of Controlled Trials databases about trials on IO antibiotics (into the proximal tibia before skin incision) to prevent infections in TKA from the respective inception dates to September 30, 2022. The infection occurred within 3 months after surgery. Both researchers individually screened the studies in accordance with the inclusion and exclusion criteria, performed the literature quality evaluation and data extraction, and used Stata 17 software for data analysis.

Results

Five studies that enrolled 3801 patients were included in this meta-analysis. The results showed that IO antibiotics were effective in reducing the incidence of SSI (OR: 0.25, P = 0.001) and periprosthetic joint infections (OR: 0.16, P = 0.004) relative to IV. Moreover, the percentage of infection due to Gram-positive bacteria (OR: 0.18, P = 0.025) was reduced in the IO group compared with that in IV group, but Gram-negative bacteria levels were not significantly reduced (P = 0.14). There was no difference between the two groups for other systemic adverse effects of the drug.

Conclusions

IO antibiotics in TKA are safe and effective alternatives to IV antibiotics. Large randomized clinical studies comparing infection rates and related complications with IO and IV antibiotics are required.

Intraosseous Vancomycin May Not Be Helpful in Aseptic Revision Knee Arthroplasty: A Single-Surgeon Consecutive Case Series

BACKGROUND

Infection after aseptic revision total knee arthroplasty (TKA) has been reported from 9% to 14%. Intraosseous (IO) vancomycin infusion has decreased the risk of infection after primary TKA. The results of this additional prophylaxis were evaluated in aseptic revision TKA.

METHODS

In this prospective, single-surgeon study of 20 consecutive patients having aseptic revision TKA, 500 milligrams of vancomycin in 120 mL of saline were infused into the tibia prior to incision, in addition to intravenous (IV) cefazolin. There were 18 men and 2 women who had a mean age of 67 years (range, 47-79), and mean body mass index of 34.4 (range, 25.9-51.2). The knees were aspirated in the operating room prior to IV and IO antibiotics. The outcomes were infections at 90 days requiring reoperation and complications from the infusion.

RESULTS

Three of the 20 aseptic revisions had early prosthetic joint infection, 2 with gram-negative organisms and one with coagulase-negative Staphylococcus. All had debridement, liner exchange and IV antibiotic treatment, but 1 patient eventually had an above knee amputation. No patient had total body "erythema syndrome", but 1 patient had transient facial flushing. Six patients had a transient elevation of serum creatinine including 3 with an abnormal preoperative serum creatinine.

CONCLUSION

In this small series of aseptic revision TKA, there was no added benefit of IO vancomycin infusion, but there were no infections with methicillin-resistant Staphylococcus aureus. Additional studies are needed before this technique should be routinely recommended.

Preoperative Prophylactic Antibiotics in Total Hip and Knee Arthroplasty: What, When, and How

Although there are numerous nonpatient-related factors that may help reduce infection risk, the proper use of prophylactic antibiotics is most responsible for reducing infection. The role of prophylactic antibiotics is to reduce early periprosthetic joint replacement, which is accomplished by having adequate antibiotic tissue levels at the time of skin incision. The goal of this section of the symposium is to review current antibiotic recommendations, how to manage patients with a self-reported penicillin allergy, review the use of dual antibiotics, discuss the use of antibiotics in the outpatient total joint setting, as well as very briefly discuss the administration of intraosseous antibiotics in knee arthroplasty.

Tourniquet use in total knee arthroplasty and the risk of infection: a meta-analysis of randomised controlled trials

Purpose

The intra-operative use of tourniquets during Total Knee Arthroplasty (TKA) is common practice. The advantages of tourniquet use include decreased operating time and the creation of a bloodless visualisation field. However, tourniquet use has recently been linked with increased post-operative pain, reduced range of motion, and slower functional recovery. Importantly, there is limited evidence of the effect of tourniquet use on infection risk. The purpose of this systematic review and meta-analysis is to fill this gap in the literature by synthesising data pertaining to the association between tourniquet use and infection risk in TKA.

Methods

A systematic literature search was performed on Pubmed, Embase, Cochrane and clinicaltrials.gov up to May 2021. Randomized control trials were included, comparing TKA outcomes with and without tourniquet use. The primary outcome was overall infection rate. Secondary outcomes included superficial and deep infection, skin necrosis, skin blistering, DVT rate, and transfusion rate.

Results

14 RCTs with 1329 patients were included. The pooled incidence of infection in the tourniquet group (4.0%, 95% CI = 2.7–5.4) was significantly higher compared to the non-tourniquet group (2.0%, 95% CI = 1.1–3.1) with an OR of 1.9 (95% CI = 1.1–3.76, p = 0.03). The length of hospital stay, haemoglobin drop (0.33 95% CI =0.12–0.54), P = 0.002) and transfusion rates (OR of 2.7, 95%CI = 1.4–5.3, P = < 0.01) were higher in the tourniquet group than the non-tourniquet group. The difference in the length of inhospital stay was 0.24 days favouring the non-tourniquet group (95% CI = 0.10–0.38, P = < 0.01). The incidence of skin blistering (OR 2.6, 95% CI = 0.7–9.9, p = 0.17), skin necrosis (OR 3.0, 95% CI = 0.50–19.3, p = 0.25), and DVT rates (OR 1.5, 95% CI = 0.60–3.60, p = 0.36) did not differ between the two groups.

Conclusion

Quantitative synthesis of the data suggested tourniquet use was associated with an increased overall risk of infection, intraoperative blood loss, need for blood transfusion and longer hospital stay. Findings of this meta-analysis do not support the routine use of tourniquet in TKA and arthroplasty surgeons should consider any potential additional risks associated with its use.

Level of evidence

meta-analysis, Level II.

Intraosseous Regional Administration of Prophylactic Antibiotics in Total Knee Arthroplasty

Prosthetic joint infection (PJI) after total knee arthroplasty is a devastating complication. With the development of antibiotic resistance, a safe and effective means of delivering antibiotic prophylaxis is needed. Intraosseous regional antibiotics (IORA) achieve higher local concentrations of antibiotics with fewer systemic side effects. Previous studies have proven the safety of IORA, whereas animal models have proven it to be more effective than intravenous antibiotics for preventing infection following surgery. Recently, large-scale retrospective studies have also demonstrated lower PJI rates following TKA when IORA is used when compared to routine intravenous prophylaxis. In this article, we propose an evidence-based method for the administration of intraosseous antibiotics in TKA, cover the up-to-date data supporting its use, and explore future directions for additional research.

Higher Tissue Concentrations of Vancomycin Achieved With Low-Dose Intraosseous Injection Versus Intravenous Despite Limited Tourniquet Duration in Primary Total Knee Arthroplasty: A Randomized Trial

BACKGROUND

Vancomycin use has been suggested in high risk patients undergoing total knee arthroplasty (TKA). Previous literature has shown that a lower dose (500 mg) of vancomycin given by intraosseous regional administration (IORA) achieves tissue concentrations 4-10 times higher than intravenous (IV) administration. There is increasing interest in performing TKA with limited tourniquet inflation time. The purpose of this study is to evaluate whether IORA of vancomycin can achieve effective tissue concentrations with limited tourniquet inflation time.

METHODS

Based on prior power calculations, 24 patients undergoing primary TKA were randomized into 2 groups. Group IV-Systemic received weight-based (15 mg/kg) vancomycin with the tourniquet inflated for cementation only. Group IORA received 500 mg vancomycin via IORA after tourniquet inflation which remained inflated for 10 minutes, then reinflated for cementation only. Vancomycin concentrations from tissue, serum, and drain fluid were compared between the 2 groups.

RESULTS

Median vancomycin concentrations in tissue were significantly higher (5-15 times) at all time points in the IORA group. Concentrations in fat at the time of wound closure, after the tourniquet had been deflated for most of the procedure, were 5.2 μg/g in Group IV-Systemic and 33.1 μg/g in Group IORA (P < .001). Median bone concentrations taken just prior to cementation were 7.9 μg/g in Group IV-Systemic and 21.8 μg/g in Group IORA (P = .006). There were no complications related to IORA.

CONCLUSION

For surgeons who wish to limit tourniquet time and when indicated to use vancomycin, low-dose vancomycin IORA achieves tissue concentrations 5-15 times higher than those achieved by IV administration.

LEVEL OF EVIDENCE

Level 1 therapeutic randomized trial.

Systemic versus free antibiotic delivery in preventing acute exogenous implant related infection in a rat model

We studied systemic ceftriaxone, and free/local tobramycin and doxycycline in a controlled rat model representing a generic acute exogenous joint infection. We hypothesized that evidence of infection (quantitative colony forming units [CFU], qualitative scanning electron microscopy [SEM], histopathology) (1a) would be reduced with local versus systemic antibiotic, (1b) any antibiotic would be superior to control, (2) there would be a difference among antibiotics, and (3) antibiotic would not be detectable in serum at 4-week euthanasia. Study groups included infected and noninfected (1) control (no treatment), (2) systemic ceftriaxone (daily), (3) local tobramycin, and (4) local doxycycline (10 rats/group; power = 0.8). With IACUC approval, a reliable acute exogenous joint infection was created by slowly injecting 50-μl, 10⁴ CFU Staphylococcus aureus, into the distal femoral medullary canal. The antibiotic formulation was introduced locally to the femoral canal and joint space. After 4 weeks, serum, pin, bone, and synovium were obtained. CFU/ml of bone and synovium were quantified using macrotiter method. SEM imaged biofilm on the surface of the pin, histopathology identified tissue response, liquid chromatography/mass spectrometry quantified plasma antibiotic. (1) Groups receiving any antibiotic reported lower CFU/ml in synovium compared with no treatment. (2) In the synovium, free/local tobramycin reduced CFU/ml to a greater extent than free/local doxycycline (p < 0.05). (3) Antibiotic in plasma after the local application was nondetectable in all groups after 4 weeks. SEM revealed no difference in biofilm on pin among all groups.

Intraosseous Regional Prophylactic Antibiotics Decrease the Risk of Prosthetic Joint Infection in Primary TKA: A Multicenter Study

BACKGROUND

Recent studies have demonstrated that the administration of regional prophylactic antibiotics by intraosseous (IO) injection achieves tissue concentrations around the knee that are 10- to 15-fold higher than intravenous (IV) delivery of prophylactic antibiotics. It is currently unknown whether the use of regional prophylactic antibiotics for primary TKA would result in a lower risk of prosthetic joint infection (PJI).

QUESTIONS/PURPOSES

(1) Is IO injection of prophylactic antibiotics associated with a decreased risk of early (< 12 months) deep PJI compared with traditional IV prophylactic antibiotics? (2) What other patient factors are associated with an increased risk of early PJI after TKA, and do regional prophylactic antibiotics influence these risk factors? (3) Can IO antibiotics be administered to all patients, and what complications occurred from the delivery of IO prophylactic antibiotics?

METHODS

A retrospective comparative study of all primary TKAs (1909 TKAs) over a 5-year period (January 2013 to December 2017) was performed to determine the risk of early PJI. Three primary TKAs did not meet the study inclusion criteria and were excluded from the study, leaving a total of 1906 TKAs (725 IO, 1181 IV) for analysis at a minimum of 12 months after index procedure. Both cohorts exhibited similar ages, BMI, and American Society of Anesthesiologists (ASA) grades; however, a greater proportion of patients in the IO cohort were smokers (p = 0.01), while a greater proportion of patients were diabetic in the IV cohort (p = 0.006). The PJI risk between IO and IV delivery techniques was compared while adjusting for patient demographics and medical comorbidities. Complications related to IO delivery-inability to administer via IO technique, compartment syndrome, fat embolism, and red man syndrome with vancomycin use-were recorded.

RESULTS

The delivery of regional prophylactic antibiotics by the IO technique resulted in a lower PJI risk than IV prophylactic antibiotics (0.1% [1 of 725] compared with 1.4% [16 of 1181]; relative risk 0.10 [95% CI 0.01 to 0.77]; p = 0.03). BMI (β = -0.17; standard error = 0.08; p = 0.02), diabetes (β = -1.80; standard error = 0.75; p = 0.02), and renal failure (β = -2.37; standard error = 0.84; p = 0.01) were factors associated with of PJI, while smoking, sex, and ASA score were not contributing factors (p > 0.05). Although BMI, diabetes, and renal failure were identified as infection risk factors, the use of IO antibiotics in these patients did not result in a lower PJI risk compared with IV antibiotics (p > 0.05). IO antibiotics were able to be successfully administered to all patients in this cohort, and there were no complications related to the delivery of IO antibiotics.

CONCLUSION

Surgeons should consider administering regional prophylactic antibiotics in primary TKA to reduce the risk of early PJI. Future randomized prospective clinical trials are needed to validate the efficacy of regional prophylactic antibiotics in reducing the PJI risk in primary TKA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Incomplete Administration of Intravenous Vancomycin Prophylaxis is Common and Associated With Increased Infectious Complications After Primary Total Hip and Knee Arthroplasty

BACKGROUND

Vancomycin is often used as antimicrobial prophylaxis in patients undergoing total hip or knee arthroplasty. Vancomycin requires longer infusion times to avoid associated side effects. We hypothesized that vancomycin infusion is often started too late and that delayed infusion may predispose patients to increased rates of surgical site infections and prosthetic joint infections.

METHODS

We reviewed clinical data for all primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients at our institution between 2013 and 2020 who received intravenous vancomycin as primary perioperative gram-positive antibiotic prophylaxis. We calculated duration of infusion before incision or tourniquet inflation, with a cutoff of 30 minutes defining adequate administration. Patients were divided into two groups: 1) appropriate administration and 2) incomplete administration. Surgical factors and quality outcomes were compared between groups.

RESULTS

We reviewed 1047 primary THA and TKA patients (524 THAs and 523 TKAs). The indication for intravenous vancomycin usage was allergy (61%), methicillin-resistant staphylococcus aureus colonization (17%), both allergy and colonization (14%), and other (8%). 50.4% of patients began infusion >30 minutes preoperatively (group A), and 49.6% began infusion <30 minutes preoperatively (group B). Group B had significantly higher rates of readmissions for infectious causes (3.6 vs 1.3%, P = .017). This included a statistically significant increase in confirmed prosthetic joint infections (2.2% vs 0.6%, P = .023). Regression analysis confirmed <30 minutes of vancomycin infusion as an independent risk factor for PJI when controlling for comorbidities (OR 5.22, P = .012).

CONCLUSION

Late infusion of vancomycin is common and associated with increased rates of infectious causes for readmission and PJI. Preoperative protocols should be created to ensure appropriate vancomycin administration when indicated.

Local Vancomycin Concentrations after Intra-articular Injection into the Knee Joint: An Experimental Porcine Study

Intra-articular injection of vancomycin may be an important antimicrobial prophylactic supplement to systemic administration in the prevention of prosthetic joint infections. In eight female pigs, 500 mg of diluted vancomycin was given by intra-articular injection into the knee joint. Microdialysis was used for dense sampling of vancomycin concentrations over 12 hours in the synovial fluid of the knee joint, and in the adjacent femoral and tibial cancellous bone and subcutaneous tissue. Venous blood samples were obtained as reference. The mean (standard deviation [SD]) peak drug concentration of vancomycin in the synovial fluid of the knee joint was 5,277 (5,668) μg/mL. Only one pig failed to reach a peak drug concentration above 1,000 μg/mL. The concentration remained high throughout the sampling interval with a mean (SD) concentration of 337 (259) μg/mL after 690 minutes. For all extraarticular compartments, the pharmacokinetic parameters (area under the concentration time-curve, peak drug concentration, and time to peak drug concentration) were comparable. The highest extraarticular mean (SD) peak drug concentration of 4.4 (2.3) μg/mL was found in subcutaneous tissue. An intra-articular injection of 500 mg diluted vancomycin was found to provide significant prophylactic mean concentrations for at least 12 hours in the synovial fluid of the knee joint. Correspondingly, the adjacent tissue and plasma concentrations were low but remained stable, signifying low risk of systemic toxic side effects and a slow release or uptake from the synovium to the systemic circulation.

Results of debridement, antibiotics, and implant retention for periprosthetic knee joint infection supplemented with the use of intraosseous antibiotics

AIMS

Debridement, antibiotics, and implant retention (DAIR) remains one option for the treatment of acute periprosthetic joint infection (PJI) despite imperfect success rates. Intraosseous (IO) administration of vancomycin results in significantly increased local bone and tissue concentrations compared to systemic antibiotics alone. The purpose of this study was to evaluate if the addition of a single dose of IO regional antibiotics to our protocol at the time of DAIR would improve outcomes.

METHODS

A retrospective case series of 35 PJI TKA patients, with a median age of 67 years (interquartile range (IQR) 61 to 75), who underwent DAIR combined with IO vancomycin (500 mg), was performed with minimum 12 months' follow-up. A total of 26 patients with primary implants were treated for acute perioperative or acute haematogenous infections. Additionally, nine patients were treated for chronic infections with components that were considered unresectable. Primary outcome was defined by no reoperations for infection, nor clinical signs or symptoms of PJI.

RESULTS

Mean follow-up for acute infection was 16.5 months (12.1 to 24.2) and 15.8 months (12 to 24.8) for chronic infections with unresectable components. Overall non-recurrence rates for acute infection was 92.3% (24/26) but only 44.4% (4/9) for chronic infections with unresectable components. The majority of patients remained on suppressive oral antibiotics. Musculoskeletal Infection Society (MSIS) host grade was a significant indicator of failure (p < 0.001).

CONCLUSION

The addition of IO vancomycin at the time of DAIR was shown to be safe with improved results compared to current literature using standard DAIR without IO antibiotic administration. Use of this technique in chronic infections should be applied with caution. While these results are encouraging, this technique requires longer follow-up before widespread adoption. Cite this article: Bone Joint J 2021;103-B(6 Supple A):185-190.

2021 Chitranjan S. Ranawat Award: Intraosseous vancomycin reduces periprosthetic joint infection in primary total knee arthroplasty at 90-day follow-up

AIMS

Infection complicating primary total knee arthroplasty (TKA) is a common reason for revision surgery, hospital readmission, patient morbidity, and mortality. Increasing incidence of methicillin-resistant Staphylococcus aureus (MRSA) is a particular concern. The use of vancomycin as prophylactic agent alone or in combination with cephalosporin has not demonstrated lower periprosthetic joint infection (PJI) rates, partly due to timing and dosing of intravenous (IV) vancomycin administration, which have proven important factors in effectiveness. This is a retrospective review of a consecutive series of primary TKAs examining incidence of PJI, adverse reactions, and complications using IV versus intraosseous (IO) vancomycin at 30-day, 90-day, and one-year follow-up.

METHODS

A retrospective review of 1,060 patients who underwent TKA between May 2016 to July 2020 was performed. There were 572 patients in the IV group and 488 in the IO group, with minimal 30 days of follow-up. Patients were followed up at regularly scheduled intervals (two, six, and 12 weeks). No differences between groups for age, sex, BMI, or baseline comorbidities existed. The IV group received an IV dose of 15 mg/kg vancomycin given over an hour preceding skin incision. The IO group received a 500 mg dose of vancomycin mixed in 150 ml of normal saline, injected into proximal tibia after tourniquet inflation, before skin incision. All patients received an additional dose of first generation cephalosporin. Evaluation included preoperative and postoperative serum creatinine values, tourniquet time, and adverse reactions attributable to vancomycin.

RESULTS

Incidence of PJI with minimum 90-day follow-up was 1.4% (eight knees) in the IV group and 0.22% (one knee) in IO group (p = 0.047). This preliminary report demonstrated an reduction in the incidence of infection in TKA using IO vancomycin combined with a first-generation cephalosporin. While the study suffers from limitations of a retrospective, multi-surgeon investigation, early findings are encouraging.

CONCLUSION

IO delivery of vancomycin after tourniquet inflation is a safe and effective alternative to IV administration, eliminating the logistical challenges of timely dosing. Cite this article: Bone Joint J 2021;103-B(6 Supple A):13-17.

Intraosseous Regional Administration of Vancomycin in Primary Total Knee Arthroplasty Does Not Increase the Risk of Vancomycin-Associated Complications

BACKGROUND

Periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is a rare but major complication. Owing to an increasing antibiotic resistance in bacteria causing PJI, vancomycin has been investigated as a prophylactic agent. Intraosseous regional administration (IORA) of vancomycin achieves significantly higher local tissue concentrations than systemic administration. There are limited data on IORA of vancomycin with respect to vancomycin-associated complications.

METHODS

Single-surgeon retrospective review of primary TKA was performed between January 2015 and May 2019. All patients received 500 mg of IORA of vancomycin after tourniquet inflation and 3 × 1 g intravenous cefazolin in 24 hrs. Preoperative data collected included age, gender, body mass index, American Society of Anesthesiologists (ASA) score, diabetes, and chronic kidney disease (CKD). We documented in-hospital complications and complications requiring readmission within 12 months. Primary outcome measures were the incidence of acute kidney injury (AKI), 'red man syndrome' (RMS), and neutropenia. The secondary outcome measure was PJI incidence.

RESULTS

We identified 631 primary TKAs in 556 patients, of which 331 received IORA. The mean age was 67.7 ± 8.7 years, and 57.8% were women. CKD was prevalent in 17.2% of the cohort. AKI occurred in 25 (3.9%) cases. After controlling for covariates, CKD was the only significant predictor of AKI (odds ratio = 3.035, P = .023). RMS and neutropenia were not observed in this cohort. The 90-day PJI rate was 0%, and the 1-year PJI rate was 0.2%.

CONCLUSIONS

Low-dose IORA of vancomycin in addition to standard intravenous systemic cefazolin prophylaxis in TKA is safe without significant adverse effects of vancomycin such as AKI, RMS, or neutropenia.

Vancomycin bone and tissue concentrations following tibial intraosseous administration - evaluated in a porcine model

Introduction. Systemic perioperative vancomycin may not provide sufficient prophylactic target-site concentrations in the prevention of prosthetic joint infections. Intraosseous vancomycin potentially provides high target-site concentrations. The objective of the present study was to evaluate the local bone and tissue concentrations following tibial intraosseous vancomycin administration in a porcine model. Methods. Eight pigs received 500 mg diluted vancomycin (50 mg/mL) through an intraosseous cannula into the proximal tibial cancellous bone. No tourniquet was applied. Microdialysis was applied for sampling of vancomycin concentrations in adjacent tibial cancellous bone, in cortical bone, in the intramedullary canal of the diaphysis, in the synovial fluid of the knee joint, and in the subcutaneous tissue. Plasma samples were obtained as a systemic reference. Samples were collected for 12 h. Results. High vancomycin concentrations were found in the tibial cancellous bone with a mean peak drug concentration of 1236 (range 28-5295)  µ g / mL , which remained high throughout the sampling period. The mean (standard deviation) peak drug concentration in plasma was 19 (2)  µ g / mL , which was obtained immediately after administration. Peak drug concentration, time to peak drug concentration, and area under the concentration-time curve were within the same range in the intramedullary canal, the synovial fluid of the knee, and the subcutaneous tissue. Conclusion. Tibial intraosseous administration of vancomycin provided high concentrations in tibial cancellous bone throughout a 12 h period but with an unpredictable and wide range of peak concentration. The systemic absorption was high and immediate, thus mirroring an intravenous administration. Low mean concentrations were found in all the remaining compartments.

Novel microcomposite implant for the controlled delivery of antibiotics in the treatment of osteomyelitis following total joint replacement

The objective of this study was to develop a novel microcomposite implant to be used in the treatment of osteomyelitis following total joint arthroplasty, with the dual purpose of releasing high local concentrations of antibiotic to eradicate the infection while providing adequate mechanical strength to maintain the dynamic or static spacer. Vancomycin-loaded microcomposite implants were fabricated by incorporating drug-loaded microparticles comprised of mesoporous silica into commonly employed polymethylmethacrylate (PMMA) bone cement, to yield a final drug loading of 10% w/w. In vitro release kinetics at 37°C were monitored by reverse-phase high-performance liquid chromatography, and compared to the release kinetics of current therapy implants consisting of drug alone incorporated at 10% w/w directly into PMMA bone cement. Results demonstrated a sevenfold improvement in the elution profile of microcomposite systems over current therapy implants. In vivo delivery of vancomycin to bone from microcomposite implants (70% of payload) was significantly higher than that from current therapy implants (approx. 22% of payload) and maintained significantly higher bone concentrations for up to 2 weeks duration. The elastic modulus showed no statistical difference between microcomposite implants and current standard therapy implants before drug elution, and maintenance of acceptable strength of microcomposite implants postdrug elution. These results demonstrate that we have developed a novel microcomposite spacer that will release continuously high antibiotic concentrations over a prolonged period of time, offering the possibility to eliminate infection and avoid the emergence of new resistant bacterial strains, while maintaining the requisite mechanical properties for proper space maintenance and joint fixation.

Intraosseous Regional Administration of Antibiotic Prophylaxis in Total Knee Arthroplasty

Background

Periprosthetic joint infection (PJI) is a devastating complication following total knee arthroplasty (TKA), and perioperative antibiotics are commonly administered to try to mitigate the chance of infection. Intraosseous regional administration (IORA) of prophylactic antibiotics during TKA is a method of antibiotic delivery that has been shown to achieve markedly higher tissue concentrations at much lower doses. Other advantages include ease of administration, ability to time the antibiotic delivery with the surgical start time for maximal effectiveness, and less systemic side effects. The concept is similar to a Bier block, except that IORA involves the use of antibiotics instead of local anesthetic to perfuse the limb and is given via intraosseous rather than intravenous access.

Description

After standard patient preparation and draping, the tourniquet is inflated and an intraosseous needle is inserted into the proximal medial face of the tibia, just medial and slightly above the level of the tubercle. A large syringe containing the desired antibiotic (typically 500 mg vancomycin suspended in normal saline solution) is connected to the needle and the solution is administered over 1 to 2 minutes. The intraosseous needle can then be removed and the surgical procedure proceeds as it normally would per surgeon preference and technique.

Alternatives

Systemic administration of intravenous antibiotics, vancomycin powder, and antibiotic-impregnated cement are alternative options that can be utilized during TKA.

Rationale

IORA has several distinct advantages over other methods of antibiotic delivery, including the ability to (1) deliver antibiotic directly to the surgical bed and avoid systemic delivery, (2) precisely time and quickly administer antibiotics to achieve highest concentrations at the start of and throughout the surgical procedure, and (3) avoid several common and potentially serious side effects, especially those associated with antibiotics such as vancomycin.

Expected Outcomes

This technique for antibiotic delivery achieves markedly higher tissue concentrations compared with systemic administration, without prolonged preoperative infusion times. Intraosseous delivery optimizes timing and reduces the risk of systemic side effects while simultaneously providing equal or enhanced antibiotic prophylaxis in TKA. This delivery mechanism is especially useful in patients who are at high risk for infection and in the revision TKA setting. Further, there is little to no additional risk and the use of this method does not substantially prolong operative time.

Important Tips

The proximal aspect of the tibia is the optimal injection site because the cortex is thinner in this region, making needle insertion easier. Additionally, the metaphyseal bone allows faster flow rates for the infusion. We have found that insertions made slightly more proximally are easier and have faster flow rates. Of note, although the antibiotic is infused into the tibia, as seen in the attached technique video, intraosseous administration achieves rapid uptake into the vascular tree. Therefore, all tissues distal to the tourniquet, including the femur and patella, will receive this optimal dose as well.We prefer the use of a power driver (EZ-IO; Teleflex); however, manual needles (Cook Medical) can also be utilized. Longer needles are available if needed for obese patients.Flow rates are variable and the infusion typically takes 1 to 2 minutes to complete. If the flow rate is slow, twisting and withdrawing the needle slightly (2 to 4 mm) may increase the rate. This contrasts with the 1 to 2-hour intravenous infusion time required when vancomycin is administered systemically.In our experience, intraosseous injection is still successful in the case of a previous high tibial osteotomy, although the flow rate may be slower.In complex revision cases with compromised proximal tibial bone, the medial malleolus is an alternative site for intraosseous administration.Choice of antibiotic: as vancomycin is difficult to adequately administer intravenously, it is ideally suited for IORA. We have studied and utilized a 500-mg dose of vancomycin suspended in a solution of 140 mL of normal saline solution (prepared by our pharmacy). Of note, we have not found rapid infusion of intraosseous vancomycin to cause red-man syndrome as it would with rapid systemic infusion. This is because of the lower dose of 500 mg and the use of the tourniquet, which keeps the antibiotic in the local tissues about the knee without allowing systemic exposure. All patients, regardless of weight or the size of their limb, receive the dose of 500 mg of vancomycin.As cefazolin does not have the same difficulties with intravenous administration, we continue to use standard intravenous prophylaxis with an appropriate weight-based dose of cefazolin prior to incision.Indications for IORA of vancomycin include clinical scenarios in which vancomycin would be administered intravenously. These indications include revision TKA, obesity (body mass index >40 kg/m²), diabetes, beta-lactam allergy, known colonization with methicillin-resistant Staphylococcus aureus (MRSA), patients coming from institutions with a high prevalence of MRSA, previous ligamentous surgical procedure or osteotomies, and current or recent smokers. IORA can be utilized even in the primary TKA setting if the patient is considered high-risk as defined by the criteria above. We also use IORA during reimplantation following 2-stage exchange for PJI and in patients undergoing irrigation and debridement for acute PJI when the organism has been identified preoperatively.

Antibiotic Stewardship for Total Joint Arthroplasty in 2020

Projections indicate an increase in primary and revision total joint arthroplasties (TJAs). Periprosthetic joint infections (PJIs) are one of the most common and devastating causes of failure after TJA. Perioperative administration of systemic and/or local antibiotics is used for both prophylaxis and treatment of PJI. Antibiotic stewardship is a term that has been met with clinical acceptance and success in other specialties of medicine. Identifying antibiotic best practice use in the fight against PJI is limited by studies that are extremely heterogeneous in their design. Variations in studies include antibiotic selection and duration, surgical débridement steps, type of antibiotic delivery (intra-articular, local, intravenous, and prolonged oral), mix of primary and revision surgery cohorts, both hip and knee cohorts, infecting organisms, and definitions of treatment success/failure. This review highlights the current challenges of antibiotic stewardship in TJA.

Clinical outcome evaluation of intraosseous vancomycin in total knee arthroplasty

Background

Vancomycin is a commonly used prophylactic antibiotic for total joint replacement surgery to protect against methicillin-resistant Staphylococcus aureus. Studies have suggested intraosseous (IO) infusions provide superior local tissue antibiotic concentration compared with intravenous (IV) access in total knee arthroplasty (TKA). We reviewed patients receiving IO vancomycin before TKA, comparing complication rates to a matched group receiving IV prophylactic vancomycin.

Methods

Retrospective review of TKA patients administered IO vancomycin (500 mg vancomycin in 200 mL normal saline), September 1, 2018 to March 1, 2019, was compared with TKAs performed with prophylactic IV vancomycin, January 1, 2018 to August 31, 2018. Before incision, an IO needle was inserted into the tibial tubercle region, delivering 100 mL of the mixed vancomycin solution. The needle was then removed and inserted into the distal femur, delivering 100 mL of the solution. Evaluation included preoperative and postoperative creatinine values, tourniquet time, and knee-related 30-day and 90-day complications. Data for primary and revision TKA surgery cases were analyzed independently.

Results

There were 100 primary and 29 revision TKA cases in the control (IV) arm and 100 primary and 19 revision TKA cases in the intervention (IO) arm, comprising a study group of 248 cases. There were fifteen 30-day complications and eighteen 90-day complications overall. No significant differences in the complication rate or creatinine values were identified between IO and IV groups.

Conclusions

IO vancomycin has an adequate safety profile in primary and revision TKA, eliminating the logistical challenge of timely prophylactic antibiotic administration.

2019 John Charnley Award: Increased risk of prosthetic joint infection following primary total knee and hip arthroplasty with the use of alternative antibiotics to cefazolin: the value of allergy testing for antibiotic prophylaxis

AIMS

The aims of this study were to characterize antibiotic choices for perioperative total knee arthroplasty (TKA) and total hip arthroplasty (THA) prophylaxis, assess antibiotic allergy testing efficacy, and determine rates of prosthetic joint infection (PJI) based on perioperative antibiotic regimen.

PATIENTS AND METHODS

We evaluated all patients undergoing primary TKA or THA at a single academic institution between January 2004 and May 2017, yielding 29 695 arthroplasties (22 705 patients), with 3411 arthroplasties in 2576 patients (11.5%) having undergone preoperative allergy testing. A series of institutional databases were combined to identify allergy consultation outcomes, perioperative antibiotic regimen, and infection-free survivorship until final follow-up.

RESULTS

Among 2576 allergy-tested patients, 2493 patients (97%) were cleared to use cephalosporins. For the entire cohort, 28 174 arthroplasties (94.9%) received cefazolin and 1521 (5.1%) received non-cefazolin antibiotics. Infection-free survivorship was significantly higher among arthroplasties receiving cefazolin compared with non-cefazolin antibiotics, with 0.06% higher survival free of infection at one month, 0.56% at two months, 0.61% at one year, and 1.19% at ten years (p < 0.001). Overall, the risk of PJI was 32% lower in patients treated with cefazolin after adjusting for the American Society of Anesthesiologists (ASA) classification, joint arthroplasty (TKA or THA), and body mass index (BMI; p < 0.001). The number needed to treat with cefazolin to prevent one PJI was 164 patients at one year and 84 patients at ten years. Therefore, potentially 6098 PJIs could be prevented by one year and 11 905 by ten years in a cohort of 1 000 000 primary TKA and THA patients.

CONCLUSION

PJI rates are significantly higher when non-cefazolin antibiotics are used for perioperative TKA and THA prophylaxis, highlighting the positive impact of preoperative antibiotic allergy testing to increase cefazolin usage. Given the low rate of true penicillin allergy positivity, and the readily modifiable risk factor that antibiotic choice provides, we recommend perioperative testing and clearance for all patients presenting with penicillin and cephalosporin allergies. Cite this article: Bone Joint J 2019;101-B(6 Supple B):9-15.

Greater Rates of Acute Kidney Injury in African American Total Knee Arthroplasty Patients

BACKGROUND

This retrospective study compared the change in serum creatinine between African American and Caucasian total knee arthroplasty (TKA) patients. The authors hypothesized that African Americans would demonstrate significantly greater change, and that a significantly greater proportion would demonstrate creatinine changes consistent with acute kidney injury (AKI).

METHODS

Primary TKAs performed at a single institution between July 2011 and June 2016 were identified: 1035 primary TKAs met inclusion and exclusion criteria (110 African American, 925 Caucasian, excluding Hispanic and Asian patients). None were excluded based on gender, age, body mass index, preoperative diagnosis, or comorbidities. All patients had preoperative and postoperative creatinine levels available in the electronic medical records. Each patient received the same preop and postop protocol for nonsteroidal anti-inflammatory drug use along with other drugs administered including anesthesia. All patients received 1 g of intravenous vancomycin with some patients additionally receiving 1 g of vancomycin powder administered locally at the end of surgery. All patients were controlled for fluid intake and blood loss, along with no patient receiving a transfusion or intravenous contrast. Patient demographics and preoperative/postoperative serum creatinine were recorded and then analyzed for presence of AKI (≥0.3 mg/dL). Preoperative/postoperative serum creatinine concentrations were compared between African American and Caucasian patients using 2 × 2 repeated measures analysis of variance. Prevalence of patients in each group demonstrating AKI was calculated using Fisher's exact test.

RESULTS

African American patients had significantly greater serum creatinine preoperatively (1.00 ± 0.26 vs 0.90 ± 0.22, P < .001) and a significantly greater increase postoperatively (0.10 vs 0.03, P < .001). A significantly greater number of African American patients demonstrated AKI (10.9% vs 5.1%, P = .03). Furthermore, a significantly greater number of African American patients stayed in the hospital an additional 2 or more days for renal issues (2.7% vs 0.4%, P = .03).

CONCLUSION

Altered renal function was significantly more common in African American TKA patients. Future studies are necessary to determine if tailoring anti-inflammatories, perioperative medications, and preoperative comorbidities reduce the risk of renal injury and/or a longer hospital stay for this subset of patients.

Use of regional administration of prophylactic antibiotics in total knee arthroplasty

Prosthetic joint infection after total knee arthroplasty is an infrequent, yet serious complication. Antimicrobial prophylaxis plays an important role in reducing the rate of surgical site infections. To be effective as an antimicrobial prophylaxis, the serum, tissue and bone concentrations of the antibiotic must be greater than the target organism's minimum inhibitory concentration. As antibiotic resistance increases current intravenous prophylactic dosing has been shown to be subtherapeutic for some patients. Intravenous regional administration and intraosseous regional administration of prophylactic antibiotics are novel methods used to increase the antibiotic tissue concentrations, which may enhance the efficacy of prophylactic antibiotics in total knee arthroplasty. Currently, literature has shown both intravenous regional administration and intraosseous regional administration to be safe and effective techniques. However, there is no clinical evidence to show that it results in a reduction of prosthetic joint infection rates. This study summarizes the current knowledge base on the use of regional administration of prophylactic antibiotics in total knee arthroplasty.

The AAHKS Clinical Research Award: Intraosseous Regional Prophylaxis Provides Higher Tissue Concentrations in High BMI Patients in Total Knee Arthroplasty: A Randomized Trial

BACKGROUND

Obesity is an established risk factor for periprosthetic joint infections after total knee arthroplasty (TKA). In obese patients, a larger dose of prophylactic vancomycin based on actual body weight is required to reach therapeutic concentrations. It is unclear how tissue concentrations are affected when intraosseous regional administration (IORA) is used in this population. This study compared tissue concentrations of low-dose vancomycin via IORA vs actual body weight-adjusted systemic intravenous (IV) dose in primary TKA.

METHODS

Twenty-two patients with a body mass index (BMI) >35 undergoing TKA were randomized into 2 groups. The IV group received 15 mg/kg (maximum of 2 g) of systemic IV vancomycin and the IORA group received 500 mg vancomycin into the tibia. Subcutaneous fat and bone samples were taken at regular intervals. Tissue antibiotic concentrations were measured using liquid chromatography coupled with tandem mass spectrometry. A blood sample was taken 1 to 2 hours after tourniquet deflation to measure systemic concentration.

RESULTS

The mean BMI was 41.1 in the IORA group and 40.1 in the IV systemic group. The overall mean tissue concentration in subcutaneous fat was 39.3 μg/g in the IORA group and 4.4 μg/g in the IV systemic group (P < .01). Mean tissue concentrations in bones were 34.4 μg/g in the IORA group and 6.1 μg/g in the IV systemic group (P < .01).

CONCLUSION

Low-dose IORA was effective in the high-BMI population group, providing tissue concentrations of vancomycin 5-9 times higher than systemic administration. IORA optimizes timing of vancomycin administration and provides high tissue antibiotic concentrations during TKA in this high-risk patient group.

The John N. Insall Award: Higher Tissue Concentrations of Vancomycin Achieved With Intraosseous Regional Prophylaxis in Revision TKA: A Randomized Controlled Trial

BACKGROUND

In primary TKA, prophylaxis with low-dose vancomycin through intraosseous regional administration (IORA) achieves tissue concentrations six to 10 times higher than systemic administration and was shown to provide more effective prophylaxis in an animal model. However, in revision TKA, the presence of a tibial implant may compromise IORA injection, and tourniquet deflation during a prolonged procedure may lower tissue concentrations.

QUESTIONS/PURPOSES

(1) Does low-dose IORA reliably provide equal or higher tissue concentrations of vancomycin compared with systemic IV administration in revision TKA? (2) Are tissue concentrations of vancomycin after IORA maintained for the duration of the revision TKA despite a period of tourniquet deflation? (3) Is there any difference in early postoperative (< 6 weeks) complications between IORA and systemic IV administration in revision TKA?

METHODS

Twenty patients undergoing aseptic revision TKA were randomized to two groups. The IV group received 1 g systemic IV prophylactic vancomycin. The IORA group received 500 mg vancomycin as a bolus injection into a tibial intraosseous cannula below an inflated thigh tourniquet before skin incision. In all patients receiving IORA, intraosseous tibial injection was technically possible despite the presence of a tibial implant. Mean procedure length was 3.5 hours in both groups. Mean initial tourniquet inflation was 1.5 hours with a second inflation for a mean of 35 minutes during cementation. During the procedure, subcutaneous fat and bone samples were taken at regular intervals. Tissue vancomycin concentrations were measured using high-performance liquid chromatography.

RESULTS

Overall geometric mean tissue concentration of vancomycin in fat samples was 3.7 μg/g (95% confidence interval [CI], 2.6-5.2) in the IV group versus 49.3 μg/g in the IORA group (95% CI, 33.2-73.4; ratio between means 13.5; 95% CI, 8.2-22.0; p < 0.001); mean tissue concentrations in femoral bone were 6.4 μg/g (95% CI, 4.5-9.2) in the IV group versus 77.1 μg/g (95% CI, 42.4-140) in the IORA group (ratio between means 12.0; 95% CI, 6.2-23.2; p < 0.001). Vancomycin concentrations in the final subcutaneous fat sample taken before closure were 5.3 times higher in the IORA group versus the IV group (mean ± SD, 18.2 ± 11.6 μg/g IORA versus 3.6 ± 2.5 μg/g; p < 0.001). The intraarticular concentration of vancomycin on postoperative Day 1 drain samples was not different between the two groups with the numbers available (mean 4.6 μg/L in the IV group versus 6.6 μg/g in the IORA group; mean difference 2.0 μg/g; 95% CI, 6.2-23.2; p = 0.08).

CONCLUSIONS

IORA administration of vancomycin in patients undergoing revision TKA resulted in tissue concentrations of vancomycin five to 20 times higher than systemic IV administration despite the lower dose. High tissue concentrations were maintained throughout the procedure despite a period of tourniquet deflation. These preliminary results justify prospective cohort studies, which might focus on broader safety endpoints in more diverse patient populations. We believe that these studies should evaluate patients undergoing revision TKA in particular, because the risk of infection is greater than in patients undergoing primary TKA.

LEVEL OF EVIDENCE

Level I, therapeutic study.

Antibiotics and antiseptics for preventing infection in people receiving revision total hip and knee prostheses: a systematic review of randomized controlled trials

BACKGROUND

Infection rates in revision (second and subsequent) major joint arthroplasty continues to be a significant issue with rates 2-3 times those of primary procedures. The effect of antibiotic and antiseptic prophylaxis on outcomes for this type of surgery has not been adequately reviewed.

METHODS

A systematic search of the main databases for randomized controlled trials (RCTs) evaluating antibiotics and antiseptics was conducted to evaluate the predetermined endpoints of infection.

RESULTS

There were five (5) RCTs identified that examined the effects of antibiotic and antiseptic prophylaxis on infections after revision total hip arthroplasty [THA] (total of 304 participants) and total knee arthroplasty [TKA] (total of 206 participants). For TKA, preoperative systemic intravenous (IV) antibiotic prophylaxis plus antibiotic cement may be effective in reducing the incidence of infection in revision TKA at 8+ years. These results however should be interpreted with caution due to the significant biases. For revision THA, there is no RCT evidence that antibiotics/antiseptics have any effect on the infection rate.

CONCLUSIONS

There is a lack of high quality data demonstrating an effect of antibiotics or antiseptics on infection rates in revision THA/TKA. Considering the rate of infections in revisions is 2-3X that of primary procedures and; there is a consensus recommendation to use similar antibiotic and antiseptic regimens in both primary and revision procedures, there is a need for high quality studies in revision THA/TKA.

Biofilm prevention of gram-negative bacterial pathogens involved in periprosthetic infection by antibiotic-loaded calcium sulfate beads in vitro

Biofilm formation represents a key stage in the pathogenesis of prosthetic infections (PIs). More tolerant to antibiotics than their planktonic counterparts, biofilm bacteria are difficult to eradicate using conventional therapeutic regimes. A common approach in PI management is the adjunctive use of localised antibiotics in addition to systemic administration in an attempt to protect the implant from colonisation by infiltrating bacteria. This study evaluates the antibacterial and antibiofilm efficacy of antibiotic-loaded dissolvable calcium sulphate, previously shown to be effective against key gram-positive pathogens, against gram-negative species important in the establishment of chronic infection in PIs. Synthetic calcium sulfate beads loaded with tobramycin, vancomycin and both antibiotics in combination were assessed for their ability to eradicate planktonic Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae strains. The efficacy of the beads in preventing biofilm formation and eliminating established biofilms over multiple days was evaluated using confocal laser scanning microscopy (CSLM) imaging combined with image analysis and viable cell counts. Beads loaded with antibiotics demonstrated effective eluting concentrations for up to 37 d depending on the bacterial strain. In the presence of repeated bacterial challenges, antibiotic-loaded beads prevented bacterial colonisation and significantly reduce biofilm formation for the duration of the assay (7 d). Complete eradication of established biofilms was more difficult with evidence of biofilm regrowth after 1 week of contact with antibiotic-loaded beads, despite data suggesting a complete kill was achieved at earlier timepoints of 24 h and 72 h in the case of K. pneumoniae and P. aeruginosa. This study provides further evidence that calcium sulfate beads loaded with vancomycin and tobramycin may be a useful adjunctive component to the successful management of PIs.

Prophylactic peri-operative local antibiotic irrigation

An extensive review of the spinal and arthroplasty literature was undertaken to evaluate the effectiveness of local antibiotic irrigation during surgery. The efficacy of antibiotic irrigation for the prevention of acute post-operative infection after total joint arthroplasty was evaluated retrospectively in 2293 arthroplasties (1990 patients) between January 2004 and December 2013. The mean follow-up was 73 months (20 to 139). One surgeon performed all the procedures with minimal post-operative infection.

The intra-operative protocol included an irrigation solution of normal saline with vancomycin 1000 mg/l and polymyxin 250 000 units/l at the rate of 2 l per hour. No patient required re-admission for primary infection or further antibiotic treatment. Two morbidly obese patients (two total hip arthroplasties) developed subcutaneous fat necrosis requiring debridement and one was revised because the deep capsular sutures were contaminated by the draining subcutaneous haematoma. One patient who had undergone total knee arthroplasty had unrecognised damage to the lateral superior geniculate artery and developed a haematoma that became infected secondarily four months after the surgery and underwent revision.

The use of antibiotic irrigation during arthroplasty surgery has been highly effective for the prevention of infection in the author’s practice. However, it should be understood that any routine prophylactic use of antibiotics may result in resistant organisms, and the wise stewardship of the use of antibiotics is an important part of surgical practice.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):23–6.

Regional Intraosseous Administration of Prophylactic Antibiotics is More Effective Than Systemic Administration in a Mouse Model of TKA

BACKGROUND

In human TKA studies, intraosseous regional administration (IORA) of prophylactic antibiotics achieves local tissue antibiotic concentrations 10 times greater than systemic administration. However, it is unclear if such high concentrations provide more effective prophylaxis.

QUESTIONS/PURPOSES

We asked: (1) What prophylaxis dosage and route (intravenous [IV] versus IORA of prophylactic antibiotics) produce less in vivo bacterial burden compared with no-antibiotic controls? (2) Compared with controls, what prophylaxis dosage and route yield fewer colony-forming units (CFUs) in euthanized animals in a model of TKA? (3) Is prophylactic IORA of antibiotics more effective than same-dose IV antibiotic administration in reducing CFUs?

METHODS

Mice (six to nine per group) were block randomized to one of six prophylaxis regimens: control, systemic cefazolin (C100IV), IORA of cefazolin (C100IORA), systemic vancomycin (V110IV), low-dose systemic vancomycin (V25IV), and low-dose IORA of vancomycin (V25IORA). Surgery involved placement of an intraarticular knee prosthesis, followed by an inoculum of bioluminescent Staphylococcus aureus strain Xen36. Biophotonic imaging assessed in vivo bacterial loads, and after 4 days bacterial load was quantified using culture-based techniques. Comparisons were made for each prophylactic regimen to controls and between same-dose IV and IORA of prophylactic antibiotic regimens.

RESULTS

Mice treated with systemic high-dose vancomycin, IORA of vancomycin, or IORA of cefazolin had lower in vivo Staphylococcus aureus burdens (median area under curve, Control: 5.0 × 10(6); V110IV: 1.5 × 10(6), difference of medians 3.5 × 10(6), p = 0.003; V25IV: 1.94 × 10(6), difference 3.07 × 10(6), p = 0.49; V25IORA: 1.51 × 10(6), difference 3.5 × 10(6), p = 0.0011; C100IORA: 1.55 × 10(6), difference 3.46 × 10(6), p = 0.0016; C100IV: 2.35 × 10(6), difference 2.66 × 10(6), p = 0.23.) Similar findings were seen with culture-based techniques on recovered implants. IORA of prophylactic antibiotics was more effective than same-dose IV administration in reducing bacterial load on recovered implants (median CFUs < 7.0 × 10(0) vs 2.83 × 10(2), p = 0.0183).

CONCLUSIONS

IORA of prophylactic cefazolin and vancomycin was more effective than the same dose of antibiotic given systemically. The effectiveness of vancomycin in particular was enhanced by IORA of prophylactic antibiotics despite using a lower dose.

CLINICAL RELEVANCE

Our study supports previous studies of IORA of prophylactic antibiotics in humans and suggests this novel form of administration has the potential to enhance the effectiveness of prophylaxis in TKA. Because of concerns regarding antibiotic stewardship, IORA of prophylactic vancomycin may be more appropriately restricted to patients having TKA who are at greater risk of infection, and clinical trials are in progress.

Titanium-Based Hip Stems with Drug Delivery Functionality through Additive Manufacturing

Postoperative infections are a major concern in patients that receive implants. These infections generally occur in areas with poor blood flow and pathogens do not always respond to antibiotic treatment. With the latest developments in nanotechnology, the incorporation of antibiotics into prosthetic implants may soon become a standard procedure. The success will, however, depend on the ability to control the release of antibiotics at concentrations high enough to prevent the development of antibiotic-resistant strains. Through additive manufacturing, antibiotics can be incorporated into cementless femoral stems to produce prosthetic devices with antimicrobial properties. With the emerging increase in resistance to antibiotics, the incorporation of antimicrobial compounds other than antibiotics, preferably drugs with a broader spectrum of antimicrobial activity, will have to be explored. This review highlights the microorganisms associated with total hip arthroplasty (THA), discusses the advantages and disadvantages of the latest materials used in hip implants, compares different antimicrobial agents that could be incorporated, and addresses novel ideas for future research.

Is potential malnutrition associated with septic failure and acute infection after revision total joint arthroplasty?

BACKGROUND

Although malnutrition has been hypothesized to increase the risk of periprosthetic joint infection (PJI), strong evidence linking the two is lacking.

QUESTIONS/PURPOSES

The purposes of this study were to determine (1) if one or more laboratory values suggestive of malnutrition is independently associated with being revised for an infected joint arthroplasty as opposed to for an aseptic failure; (2) the relationship between laboratory parameters suggestive of malnutrition and obesity; and (3) if one or more laboratory parameters suggestive of malnutrition is independently associated with acute PJI complicating an aseptic revision procedure.

METHODS

Between 2002 and 2010, one surgeon performed 600 revision total joint arthroplasties in 547 patients; during that time, nutritional parameters (including serum albumin, total lymphocyte count, and transferrin) were routinely obtained preoperatively; complete data sets were available on 454 patients (501 procedures [84%]). We compared the frequency of having one or more laboratory parameters suggestive of malnutrition between patients undergoing a revision for septic reasons and aseptic reasons as well as between obese and nonobese patients. The 375 aseptic revisions were then assessed for the incidence of acute postoperative infection (within 90 days, diagnosed with Musculoskeletal Infection Society criteria). Multivariate logistic regression modeling was used to evaluate factors independently associated with (1) a septic as opposed to an aseptic mode of failure; and (2) acute postoperative infection after an aseptic revision.

RESULTS

Patients in 67 of 126 (53%) revisions for PJI had one or more laboratory parameters suggestive of malnutrition compared with 123 of 375 (33%) undergoing revision for a noninfectious etiology (odds ratio [OR], 2.3 [95% confidence interval, 1.5-3.5]; p<0.001). Patients who were of normal weight at the time of revision had the highest frequency of laboratory parameters suggestive of malnutrition (42 of 82 [51%]), although this was common in obese patients as well (76 of 238 [32%]) (p=0.002). Among the 375 aseptic revisions, 12 developed an acute postoperative infection (3%). The frequency of infection was nine of 123 in the group having one or more laboratory parameters suggestive of malnutrition and three of 252 in the group not having such laboratory parameters (7% versus 1%; p=0.003). Multivariate regression revealed that having laboratory parameters suggestive of malnutrition is independently associated with both chronic PJI (p=0.003; OR, 2.1) and an acute postoperative infection complicating an aseptic revision arthroplasty (p=0.02; OR, 5.9).

CONCLUSIONS

Having one or more laboratory parameters suggestive of malnutrition is common among patients undergoing revision arthroplasty and is independently associated with both chronic septic failure and acute postoperative infection complicating a revision performed for a noninfectious etiology. Future studies should assess the impact of a standardized screening protocol with subsequent correction of abnormal laboratory parameters suggestive of malnutrition on the risk of PJI to determine a potential causal relationship between the two.

LEVEL OF EVIDENCE

Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Clinical experimentation with aerosol antibiotics: current and future methods of administration

Currently almost all antibiotics are administered by the intravenous route. Since several systems and situations require more efficient methods of administration, investigation and experimentation in drug design has produced local treatment modalities. Administration of antibiotics in aerosol form is one of the treatment methods of increasing interest. As the field of drug nanotechnology grows, new molecules have been produced and combined with aerosol production systems. In the current review, we discuss the efficiency of aerosol antibiotic studies along with aerosol production systems. The different parts of the aerosol antibiotic methodology are presented. Additionally, information regarding the drug molecules used is presented and future applications of this method are discussed.