Prophylactic antibiotics in orthopaedic surgery

Surgical site infections after sarcoma resections in the peripelvic region: do we need perioperative antibiotic prophylaxis?

Introduction

Surgical site infections (SSI) are one of the most common complications after extensive sarcoma resections and represent a daily challenge. SSI occur in up to 50% of cases particularly in the peripelvic area. One possible approach to reduce infection rate is perioperative antibiotic prophylaxis. The aim of this study therefore was to investigate the influence of perioperative antibiotic prophylaxis on the infection rate and the possible influence of location-specific antibiotic prophylaxis with ampicillin/sulbactam.

Methods

This monocentric retrospective study included 366 patients who underwent sarcoma resections in the groin, proximal thigh, or gluteal region. All patients were operated on by 2 surgeons after neoadjuvant pretreatment if necessary. 3 groups of patients were defined. Group 1: In 60.4% of all cases, antibiotic prophylaxis was administered with cephalosporins (also clindamycin in case of penicillin allergy). Group2: In 9.8% of cases, ampicillin/sulbactam was used. Group 3: 29.8% of patients did not receive any antibiotic prophylaxis.

Results

In 31.1% of treated cases, antibiotic therapy was prolonged due to extended tumor resections. Postoperative infections occurred in 23.2% (85 cases), in 77 cases within the first 90 days (on average after 20 days). The median operating time, blood loss was higher, and tumor size were significantly larger in cases with infections, compared to patients without infection. In group 1 and 2 with perioperative single-shot prophylaxis, infection occurred in 24.1% of cases, compared to 13.5% of cases without prophylaxis (group 3) (p= 0.032). In the patients with prolonged antibiotic therapy, infection occurred in 31.6% of cases, compared to 16.3% of cases without prolongation (p< 0.001). In the group 2, infection occurred in 19.4% of cases compared to 24.9% of cases in the group 1 (p= 0.479). In the multivariate analysis, surgery time longer 80 min, blood substitution, neoadjuvant radio- and chemotherapy proved to be a risk factor for SSI.

Discussion

Region adapted perioperative antibiotic prophylaxis may reduce the risk of infection after extended sarcoma resection in the peripelvic area. However, the particular bacterial spectrum of this anatomic region should be taken into account when deciding which antibiotics to use.

Local cefuroxime tissue concentrations in the hand after single and repeated administration to 16 patients undergoing trapeziectomy: a randomized controlled trial

BACKGROUND AND PURPOSE

 The duration of antibiotic coverage in hand tissues during surgery is unknown. We investigated the time the free concentration of cefuroxime was above the minimal inhibitory concentration (fT>MIC) of 4 μg/mL in hand tissues after single and repeated administration.

METHODS

 In a prospective, unblinded randomized study 16 patients (13 female, age range 51-80 years) underwent trapeziectomy. Microdialysis catheters were placed in the metacarpal bone (primary effect parameter), synovial sheath, and subcutaneous tissue. Patients were randomized to postoperative administration of either intravenous single administration of cefuroxime (1,500 mg) (Group 1, n = 8) or repeated dosing (2 x 1,500 mg) with a 4 h interval (Group 2, n = 8). Samples were taken over 8 h.

RESULTS

The fT>MIC of 4 μg/mL was found to be significantly longer in the metacarpal bone in Group 2 compared with Group 1 with a mean difference of 199 min (95% confidence interval 158-239). The same trend was evident in the remaining compartments. A concentration of 4 μg/mL was reached in all compartments in both groups within a mean time of 6 min (range 0-27 min). In Group 1, the mean concentrations decreased below 4 μg/mL between 3 h 59 min and 5 h 38 min.

CONCLUSION

 The fT>MIC was longer after repeated administration compared with single administration in all compartments. A single administration of cefuroxime 1,500 mg provided antimicrobial hand tissue coverage for a minimum of 3 h 59 min. Cefuroxime administration in hand surgeries should be done minimum 27 min prior to incision to achieve sufficient coverage in all individuals. Cefuroxime readministration should be considered in hand surgeries lasting longer than 4 h from time of administration.

Effectiveness of vancomycin powder for preventing postoperative spinal infection

OBJECTIVE

This study aimed to assess the effectiveness of Vancomycin Power (VP) and the occurrence of resistant organisms after four-year of routine VP use.

METHODS

The study included 1063 patients who underwent posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) between January 2010 and February 2020. Intrawound VP was applied to all instrumented fusions starting in January 2016. The patients were divided into two groups: those who did not apply VP (non-VP) (n = 605) between 2010 and 2015, and those who did apply VP (VP) (n = 458) between 2016 and 2020. The baseline characteristics, clinical symptoms, infection rate, and causative organisms were compared between the two groups.

RESULTS

The rate of PSI was not significantly different between the non-VP group (1.32 %, n = 8) and the VP group (1.09 %, n = 5). Although adjusted by diabetes mellitus, VP still did not show statistical significance (OR = 0.757 (0.245-2.345), p = 0.630). There were no critical complications that were supposed to relation with vancomycin powder. In the 13 cases of PSI, seven pathogens were isolated, with a gram-negative organism identified in the non-VP group. However, the type of organism was not significantly different between the two groups.

CONCLUSIONS

The use of intrawound VP may not affect the PSI and occurrence of resistant organism and may not cause critical complications. Therefore, clinicians may decide whether to use VP for preventing PSI not worrying about its safety.

Effect of Vancomycin, Gentamicin and Clindamycin on Cartilage Cells In Vitro

BACKGROUND

The treatment of grafts with vancomycin for ligament reconstruction in knee surgery is the current standard. However, high antibiotic concentrations have chondrotoxic effects.

PURPOSE

To test the chondrotoxicity of clindamycin, gentamicin and vancomycin in comparable concentrations. In vitro and in vivo effective concentrations hugely vary from drug to drug. To allow for comparisons between these three commonly used antibiotics, the concentration ranges frequently used in orthopedic surgical settings were tested.

STUDY DESIGN

Controlled laboratory study.

METHODS

Human cartilage from 10 specimens was used to isolate chondrocytes. The chondrocytes were treated with clindamycin (1 mg/mL and 0.5 mg/mL), gentamicin (10 mg/mL and 5 mg/mL) or vancomycin (10 mg/mL and 5 mg/mL), at concentrations used for preoperative infection prophylaxis in ligament surgery. Observations were taken over a period of 7 days. A control of untreated chondrocytes was included. To test the chondrotoxicity, a lactate dehydrogenase (LDH) test and a water-soluble tetrazolium salt (WST-1) assay were performed on days 1, 3 and 7. In addition, microscopic examinations were performed after fluorescence staining of the cells at the same time intervals.

RESULTS

All samples showed a reasonable vitality of the cartilage cells after 72 h. However, clindamycin and gentamicin both showed higher chondrotoxicity in all investigations compared to vancomycin. After a period of 7 days, only chondrocytes treated with vancomycin showed reasonable vitality.

CONCLUSIONS

The preoperative treatment of ligament grafts with vancomycin is the most reasonable method for infection prophylaxis, in accordance with the current study results regarding chondrotoxicity; however, clindamycin and gentamicin cover a wider anti-bacterial spectrum.

CLINICAL RELEVANCE

The prophylactic antibiotic treatment of ligament grafts at concentrations of 5 mg/mL or 10 mg/mL vancomycin is justifiable and reasonable. In specific cases, even the use of gentamicin and clindamycin is appropriate.

Overview of Antibiotic Prophylaxis in Orthopaedic and Cardiac Procedures

Antibiotic prophylaxis (AP) in surgical procedures is commonly used to prevent infections that may occur after operations. There are multiple factors that can contribute to increased risk of postsurgical complications that include prolonged hospitalization, reoperation, and readmissions. One of the strategies of decreasing the risk of bacterial contamination and developing infections is preprocedural antibiotic administration. When selecting an appropriate antibiotic, it is important to take into account surgery type and patient's characteristics which would also impact timing of administration and prophylaxis duration. Although surgical AP is significant for avoiding bacterial complications, it is also associated with some drawbacks such as increased antibiotic resistance and development of adverse reactions. Therefore, it is important to assess risks and benefits and select the most appropriate antibiotic regimen before initiating AP.

Antibiotic Prophylaxis in Clean Hand Surgery: A Prospective Cohort Analysis of Major and Minor Complications

Purpose

The indications for prophylactic antibiotics in hand surgery remain undefined. Current literature has focused solely on readmission and reoperation for surgical site infection, while neglecting minor infectious complications treated at outpatient follow-up in addition to complications from antibiotic therapy observed after surgery. This study sought to analyze major and minor infection rates, as well as adverse effects of preoperative antibiotics after clean hand surgery.

Methods

A prospective cohort study was conducted over a 6-month period. The cohorts included patients who received preoperative antibiotic prophylaxis and those that did not. Patient details and operative data were obtained during the first postoperative visit following the index surgery. Primary outcomes assessed were as follows: (1) major infection, defined as admission or reoperation for infection; (2) minor infection, defined as use of postoperative oral antibiotics; and (3) complications of antibiotic therapy.

Results

A total of 377 consecutive patients underwent operations of the upper extremity. Complications from preoperative antibiotic therapy were seen in 6.9% of patients. Overall, there were no major postoperative infections and the minor postoperative infection rate was 5.6%. The minor infection rate was 6.9% (9/131) among patients who did not receive preoperative antibiotics and 4.9% (12/246) among patients who received preoperative antibiotics (P = .57).

Conclusions

A 5.6% minor infection rate was identified following clean hand surgery, with no cases of major infection. Preoperative antibiotics did not demonstrate benefit in terms of reduction of minor infections, but they did yield a 6.9% adverse reaction rate, including one case of Clostridium difficile infection warranting hospitalization. Caution is recommended while prescribing prophylactic antibiotics for clean hand surgeries, given the lack of clear benefits and the potential for adverse effects.

Type of Study/level of evidence

Prognostic II.

The Impact of Clinical Practice Guidelines on Preoperative Antibiotic Administration for Carpal Tunnel Release

Background: In 2015, the American Association of Plastic Surgeons (AAPS) published a consensus statement against the routine use of preoperative antibiotic prophylaxis to prevent surgical site infection in clean hand surgery. The American Academy of Orthopaedic Surgeons (AAOS) similarly cited "insufficient evidence" in its Appropriate Use Criteria guidelines to support the use of antibiotics in carpal tunnel surgery. Nonetheless, its administration remains a common practice during clean hand surgery. We sought to evaluate the impact of the above guidelines on preoperative antibiotic administration. Methods: An institutional review board-approved retrospective chart review of consecutive patients with carpal tunnel syndrome treated with open carpal tunnel release (CTR) at our institution was performed in the 2 years before and after publication of AAPS/AAOS guidelines. Patient demographics and surgical outcomes were reviewed. Incidence of antibiotic administration, patient demographics, and surgeon factors were collected. Results: A total of 770 primary open CTR procedures were performed in the studied years. In 2013 and 2014, 83.9% of patients received preoperative antibiotics. In 2017 and 2018, 48.2% of patients received preoperative antibiotics. Of the variables analyzed, immunosuppression, history of diabetes, and poorly controlled diabetes (A1c > 7) were found to be statistically significant in its positive correlation to prophylactic preoperative antibiotic use. Diabetes was not associated with surgical site infections. Conclusion: Patients were more likely to receive preoperative antibiotics before the publication of the AAPS/AAOS clinical practice guidelines. Patients with diabetes regardless of their glycemic control are more likely to receive preoperative antibiotics.

Open tibial shaft fractures: treatment patterns in sub-Saharan Africa

Objective

Open tibial shaft fractures are a leading cause of disability worldwide, particularly in low and middle-income countries (LMICs). Guidelines for these injuries have been developed in many high-income countries, but treatment patterns across Africa are less well-documented.

Methods

A survey was distributed to orthopaedic service providers across sub-Saharan Africa. Information gathered included surgeon and practice setting demographics and treatment preferences for open tibial shaft fractures across 3 domains: initial debridement, antibiotic administration, and fracture stabilization. Responses were grouped according to country income level and were compared between LMICs and upper middle-income countries (UMICs).

Results

Responses from 261 survey participants from 31 countries were analyzed, with 80% of respondents practicing in LMICs. Most respondents were male practicing orthopaedic surgeons at a tertiary referral hospital. For all respondents, initial debridement occurred most frequently in the operating room (OR) within the first 24 hours, but LMIC surgeons more frequently reported delays due to equipment availability, treatment cost, and OR availability. Compared with their UMIC counterparts, LMIC surgeons less frequently confirmed tetanus vaccination status and more frequently used extended courses of postoperative antibiotics. LMIC surgeons reported lower rates of using internal fixation, particularly for high-grade and late-presenting fractures.

Conclusions

This study describes management characteristics of open tibial shaft fractures in sub-Saharan Africa. Notably, there were reported differences in wound management, antibiotic administration, and fracture stabilization between LMICs and UMICs. These findings suggest opportunities for standardization where evidence is available and further research where it is lacking.

Level of Evidence

VI-Cross-Sectional Study.

Knowledge and attitudes of orthopedic surgeons regarding prosthesis joint infection

BACKGROUND

Periprosthetic joint infection (PJI) is a critical complication after joint arthroplasty and is accompanied by increasing rates of morbidity and mortality. Several studies have aimed at preventing PJI.

AIM

To research the knowledge level and attitudes of orthopedic surgeons, who play a key role in both preventing and managing PJI.

METHODS

We conducted a web-based survey to evaluate orthopedic surgeons' knowledge level and attitudes regarding PJI. The Likert scale survey utilized consisted of 30 questions which were prepared based on the "Proceedings of the International Consensus on Periprosthetic Joint Infection".

RESULTS

A total of 264 surgeons participated in the survey. Their average age was 44.8, and 173 participants (65.5%) had more than 10 years of experience. No statistically significant relationship was found between the PJI knowledge of the surgeons and their years of experience. However, participants who worked in training and research hospitals demonstrated higher levels of knowledge than the ones in the state hospitals. It was also noticed that surgeons' knowledge concerning the duration of antibiotic therapy and urinary infections was not consistent with their attitudes.

CONCLUSION

Even though orthopedic surgeons have adequate knowledge about preventing and managing PJI, their attitudes might contradict their knowledge. Future studies are required to examine the causes and solutions of the contradictions between orthopedic surgeons' knowledge and attitudes.

How Does Medical Policy on the Use of Prophylactic Antibiotics Affect Medical Costs, Length of Hospital Stay, and Antibiotic Use in Orthopedics?

PURPOSE

The purpose of this study was to compare patients who had undergone spine surgery (SS) and hip arthroplasty surgery (HAS) and to analyze how medical policies drawn from "The Evaluation of the Appropriate Use of Prophylactic Antibiotics" have affected length of hospital stay (LOS), direct medical costs (DMC), and the duration of antibiotics use in Korea.

MATERIALS AND METHODS

This retrospective nationwide study identified subjects from the Korean National Health Insurance Review and Assessment Service database from January, 2011 to December, 2018. Evaluation of HAS (control group) was implemented in 2007, and that for SS (case group) was conducted for the first time in 2014 (intervention time). In our comparative interrupted time series analysis, we compared DMC, LOS, and use of antibiotics between both groups.

RESULTS

177468 patients who underwent SS and 89372 patients who underwent HAS were included in the study. In 2016, DMC increased for HAS, compared to SS, by 1.03 times (p=0.041). However, cost changes during other observational periods for SS were not higher than those for HAS (p>0.05). SS incurred a reduced LOS of 3% in the first 2 years (p<0.05). Thereafter, LOS changes in SS were not smaller than those in HAS. A decrease in the usage of total antibiotics and broad spectrum antibiotics was observed for 5 years.

CONCLUSION

This medical policy was effective in terms of reducing usage and duration of antibiotics use, especially in the first 2 years after the implementation of the policy.

Infections of Tumor Prostheses: An Updated Review on Risk Factors, Microbiology, Diagnosis, and Treatment Strategies

Several causes contribute to the high infection rate in tumor prostheses, including extensive tissue dissection and patients' immunosuppression due to the neoplastic disease. Most of these infections develop within the first 2 years following surgery with 70% of them occurring during the first year, while they are often associated with a low pathogen burden. The pathogenesis of infections in tumor prostheses is linked to bacteria developing in biofilms. Approximately half of them are caused by Staphylococcus spp., followed by Streptococcus spp., Enterococcus spp., and Enterobacteriaceae spp., while multiple pathogens may be isolated in up to 25% of the cases, with coagulase-negative Staphylococci (CoNS) and Enterococccus spp. being the most frequent pair. Although early detection and timely management are essential for complete resolution of these challenging infections, prompt diagnosis is problematic due to the highly varying clinical symptoms and the lack of specific preoperative and intraoperative diagnostic tests. Surgical management with one- or two-stage revision surgery is the mainstay for successful eradication of these infections. The recent advances in laboratory diagnostics and the development of biofilm-resistant prostheses over the past years have been areas of great interest, as research is now focused on prevention strategies. The aim of this study is to review and consolidate the current knowledge regarding the epidemiology, risk factors, microbiology, and diagnosis of infections of tumor prostheses, and to review the current concepts for their treatment and outcomes.

Enhanced recovery (fast-track surgery) after total ankle replacement: The state of the art

The post-operative results of a total ankle replacement are not determined solely by an optimal surgical technique, but by an appropriate anesthesiological and rehabilitative post-operative approach. Enhanced functional recovery often depends on a multidisciplinary approach based on a correct framework of the patient and his needs, requests, and characteristics. Extensive bibliographical research has been performed on Pubmed, Google Scholar, Scopus. This comprehensive and inclusive review of the literature aims to examine the state of the art of "fast-track" protocols employed in total ankle replacement (TAR), considering pre-operative preparation, anesthetic management, intraoperative and surgical factors, post-operative rehabilitative care and reduction of hospitalization time.

Dual Antibiotic Prophylaxis in Primary Total Knee Arthroplasty-No Benefit for Extremely Obese Patients

We performed this study to assess the effectiveness of multimodal total knee arthroplasty prosthetic joint infection (TKA-PJI) prophylaxis including "on-time" dual-antibiotic prophylaxis, and the influence of body mass index (BMI) on prophylaxis effectiveness. After obtaining Institutional Review Board approval, we assessed 1,802 primary TKAs (1,496 patients) who received cefazolin alone or cefazolin combined with vancomycin for TKA-PJI prophylaxis. A detailed chart review was performed to determine patient demographic features (age, gender, BMI, American Society of Anesthesiologists Score), antibiotic selection, vancomycin administration timing, and 1-year PJI rates. Statistical assessment was accomplished using a two-sided Student's t-test or Fisher's exact test. Patients who received dual-antibiotic prophylaxis with "on time" vancomycin infusion (Group CVt) had significantly lower infection rates than other TKA patients (0.8 vs. 2.7%, p < 0.01). "On Time" vancomycin administration was associated with a lower TKA-PJI rate for patients with a BMI < 45 kg/m² (0.5 vs. 2.6%, p < 0.01) with no infections in 120 TKA patients with a BMI between 40 and 44.9 kg/m² (p < 0.01). No difference was noted for patients with a BMI ≥ 45 kg/m² (3.3 vs. 2.6%, p = 0.71). There were no infections in 150 TKA patients with a normal BMI (18-25 kg/m²) in any PJI-prophylaxis treatment group. Adoption of a dual-antibiotic prophylaxis approach can successfully reduce TKA-PJI rates among overweight and moderately obese patients. The approach does not appear to influence outcomes for low risk patients with a normal BMI (18-25 kg/m²) or for higher risk patients with a BMI > 45 kg/m².

Cefuroxime concentrations in the anterior and posterior column of the lumbar spine - an experimental porcine study

BACKGROUND CONTEXT

Surgical site infection following spine surgery is associated with increased morbidity and mortality. Perioperative antibiotic prophylaxis is a key factor in lowering the risk of acquiring an infection. Previous studies have assessed perioperative cefuroxime concentrations in the anterior column of the cervical spine with an anterior surgical approach. However, the majority of surgeries are performed in the posterior column and many surgeries involve the lumbar spine.

PURPOSE

The objective of this study was to compare the perioperative tissue concentrations of cefuroxime in the anterior and posterior column during lumbar spine surgery with a posterior surgical approach.

STUDY DESIGN

In vivo experimental pharmacokinetic study of cefuroxime concentrations in an acute preclinical porcine model.

METHODS

The lumbar vertebral column was exposed from L1 to L5 in 8 female pigs. Microdialysis catheters were placed for sampling in the anterior column (vertebral body) and posterior column (posterior arch) within the same vertebra (L5). Cefuroxime (1.5 g) was administered intravenously. Microdialysates and plasma samples were continuously obtained over 8 hours. Cefuroxime concentrations were quantified by Ultra High Performance Liquid Chromatography Tandem Mass Spectrometry. The primary endpoint was the time above the cefuroxime clinical breakpoint minimal inhibitory concentration (T>MIC) for Staphylococcus aureus of 4 µg/mL. The secondary endpoint was tissue penetration (AUC_tissue/AUC_plasma).

RESULTS

Mean T>MIC 4 µg/mL (95% confidence interval) was 123 min (105-141) in plasma, 97 min (79-115) in the anterior column and 93 min (75-111) in the posterior column. Tissue penetration (95% confidence interval) was incomplete for both the anterior column 0.48 (0.40-0.56) and posterior column 0.40 (0.33-0.48).

CONCLUSIONS

T>MIC was comparable between the anterior and posterior column. Mean cefuroxime concentrations decreased below the clinical breakpoint minimal inhibitory concentration for S. aureus of 4 µg/mL after 123 minutes (plasma), 97 minutes (anterior column) and 93 minutes (posterior column). This is shorter than the duration of most lumbar spine surgeries, and therefore alternative dosing regimens should be considered in posterior open lumbar spine surgeries lasting more than 1.5 hours.

CLINICAL SIGNIFICANCE

Open lumbar spine surgery often involves extensive soft tissue dissection, stripping and retraction of the paraspinal muscles which may impair the local blood flow exposing the lumbar vertebra to postoperative infections. A single intravenous administration of 1.5 g cefuroxime only provided sufficient prophylactic target tissue concentrations in the vertebra of the lumbar spine for up to 1.5 hours.

Efficacy of Postoperative Oral Antibiotics in Foot and Ankle Surgery

BACKGROUND

Preoperative oral antibiotic use in patients undergoing foot and ankle surgery is standard practice, but no consensus has been reached regarding the efficacy of postoperative oral antibiotics. The purpose of this study was to determine whether postoperative oral antibiotics reduce the rate of surgical site infections (SSIs) in patients, with and without comorbidities, undergoing foot and ankle surgery.

METHODS

A retrospective chart review was conducted identifying patients who underwent foot and ankle surgery by 4 fellowship-trained, foot and ankle orthopaedic surgeons between January 1, 2015, and January 1, 2019. Patients were divided into 2 groups: those who received postoperative oral antibiotics (group 1) and those who did not (group 2). Two surgeons routinely prescribed postoperative oral antibiotics, and 2 did not. Demographics, comorbidities, and procedure complexity based on surgical site and Current Procedural Terminology code were recorded from the charts. The primary outcome was postoperative infection (superficial or deep) within 6 months after surgery. Patients with antibiotic use prior to surgery, preoperative infection, or lack of follow-up >6 weeks were excluded. Multivariate logistic regression modeling was used to analyze differences in infection rate and severity.

RESULTS

Chart review identified 3631 patients, 1227 of whom did not receive postoperative oral antibiotics whereas 2394 patients did. Routine postoperative oral antibiotic use did not significantly affect postoperative infection rates or severity. However, all covariates studied (diabetes, hypertension, obesity, tobacco use, alcohol use, rheumatoid conditions, and age) influenced postoperative infection rates and severity.

CONCLUSION

The results of this study indicate that postoperative oral antibiotics are not associated with differences in infection rates or severity. We do not recommend routine use in foot and ankle surgery.

Hold the Antibiotics: Are Preoperative Antibiotics Unnecessary in the Treatment of Pediatric Supracondylar Humerus Fractures?

BACKGROUND

Supracondylar humerus (SCH) fracture is the most common elbow injury in children and often treated with closed reduction and percutaneous pinning (CRPP). There is little published evidence supporting or refuting the use of perioperative prophylactic antibiotics for SCH CRPP in the pediatric population. The purpose of this study is to evaluate the rate of surgical site infection for patients with and without preoperative antibiotics.

METHODS

A retrospective chart review was conducted of patients less than or equal to 16 years from 2012 to 2018 who underwent primary CRPP. Open fractures, multilimbed polytraumas, and immunodeficient patients were excluded. Infection rates were compared using a noninferiority test assuming a 3% infection rate and a predefined noninferiority margin of 4%. A total of 255 patients were needed to adequately power the study.

RESULTS

Of the 1253 cases identified, 845 met eligibility criteria. A total of 337 received antibiotics, and 508 did not. Preoperative nerve injury (P=0.0244) and sterilization technique (P<0.0001) were associated with antibiotic use: 4 patients developed an infection; there were successfully treated superficial infections, and 1 was a deep infection requiring a formal debridement. There were 8 patients that had a recorded mal-union, and 6 patients required additional procedures; 1 patient had a postoperative compartment syndrome on postoperation day 1. The infection rates among patients treated with and without antibiotics were 0.60% and 0.40%, respectively. The absence of antibiotics was not clinically inferior to using antibiotics (P=0.003).

CONCLUSIONS

Infection remains a rare complication following CRPP of SCH fractures. According to our current data, not giving perioperative antibiotics was not inferior to using perioperative antibiotics for preventing superficial or deep infection in patients undergoing CRPP of SCH fractures. With the increase in attention to antibiotic stewardship, it is important to eliminate unnecessary antibiotic use while continuing to maintain a low rate of surgical site infection.

LEVEL OF EVIDENCE

Level IV-case series. This is a therapeutic study that investigates the results from a case series.

Variation Among Surgeons Regarding the Use of Preoperative Antibiotics in Percutaneous Pinning Procedures of the Upper Extremity in the Pediatric Population

Background: Preoperative antibiotics may not be necessary, given the very low infection rates associated with percutaneous pinning (PP) procedures of the upper extremity (UE). The purpose of this study was to determine the patterns and variation surrounding the use of preoperative antibiotics when performing PP procedures of the child's UE. Methods: A survey was sent to all members of Pediatric Orthopedic Society of North America to assess the use and opinions regarding preoperative antibiotics for PP procedures of the UE. Queries included the surgeon's current practice and thoughts regarding the need for preoperative antibiotics based on the anatomical location of the procedure. Results: Eight-one percent of the 295 respondents routinely order preoperative antibiotics for all PP procedures of the UE; however, only 60% felt that all patients must receive preoperative antibiotics. The requirement for preoperative antibiotics varied based on the anatomical location-81% for shoulder, 70% for elbow, 66% for wrist, and 62% for hand/finger. Canadian surgeons were significantly less likely to believe that preoperative antibiotics must be used in all UE cases, all shoulder cases, and all elbow cases (all Ps = .04). Conclusion: The vast majority (81%) of surgeons surveyed routinely prescribe antibiotics for PP procedures of the UE despite the fact that 40% of surgeons felt that antibiotics were not necessary for all procedures. As the PP procedure is performed more distally on the UE, fewer surgeons feel preoperative antibiotics are necessary. Future studies assessing infection rates with and without the use of preoperative antibiotics are necessary to determine the true need for these medications.

Association of Methicillin-Resistant Coagulase-Negative Staphylococci on Preoperative Skin and Surgical Site Infection in Patients Undergoing Spinal Surgery: A Retrospective Cohort Study

Introduction

The aim of this study was to investigate the association of methicillin-resistant coagulase-negative staphylococci (MRCNS) on preoperative skin and surgical site infections (SSIs) in patients undergoing spinal surgery.

Methods

A total of 507 cases (239 males and 268 females; mean age: 56.1 years) were included in this retrospective study, using prospectively collected data. All patients underwent skin culturing of the surgical site preoperatively. To identify independent risk factors for SSIs as the dependent variable, sequential multivariate logistic regression analyses were conducted. Age, sex, body mass index, presence of rheumatoid arthritis (RA), steroid uses, the American Society of Anesthesiologists Physical Status (ASA-PS) ≥3, MRCNS-positivity on skin bacterial culture, instrumentation, and Japanese Orthopedic Association (JOA) score were used as independent variables.

Results

Preoperatively, MRCNS was detected from skin culture in 50 (9.9%) cases. The frequency of RA, steroid uses, and ASA-PS ≥3 was significantly higher in MRCNS-positive cases than in MRCNS-negative cases. There were 21 (4.1%) post-spinal surgery SSI cases. Multivariate logistic regression analyses revealed that JOA scores (odds ratio (OR), 0.864; 95% confidence interval (CI), 0.764-0.977) and MRCNS-positivity (OR, 5.060; 95% CI, 1.787-14.323) were significantly associated with SSIs.

Conclusions

Preoperatively, the incidence of MRCNS was 9.9%; it was the most common cause of postoperative SSIs. MRCNS-positivity was the most associated factor for SSIs.

Prophylactic Effects of NFκB Essential Modulator–Binding Domain Peptides on Bone Infection: An Experimental Study in a Rabbit Model

Introduction

Methods

Results

Conclusion

Bioinspired Polydopamine Coatings Facilitate Attachment of Antimicrobial Peptidomimetics with Broad-Spectrum Antibacterial Activity

The prevention and treatment of biofilm-mediated infections remains an unmet clinical need for medical devices. With the increasing prevalence of antibiotic-resistant infections, it is important that novel approaches are developed to prevent biofilms forming on implantable medical devices. This study presents a versatile and simple polydopamine surface coating technique for medical devices, using a new class of antibiotics—antimicrobial peptidomimetics. Their unique mechanism of action primes them for activity against antibiotic-resistant bacteria and makes them suitable for covalent attachment to medical devices. This study assesses the anti-biofilm activity of peptidomimetics, characterises the surface chemistry of peptidomimetic coatings, quantifies the antibacterial activity of coated surfaces and assesses the biocompatibility of these coated materials. X-ray photoelectron spectroscopy and water contact angle measurements were used to confirm the chemical modification of coated surfaces. The antibacterial activity of surfaces was quantified for S. aureus, E. coli and P. aeruginosa, with all peptidomimetic coatings showing the complete eradication of S. aureus on surfaces and variable activity for Gram-negative bacteria. Scanning electron microscopy confirmed the membrane disruption mechanism of peptidomimetic coatings against E. coli. Furthermore, peptidomimetic surfaces did not lyse red blood cells, which suggests these surfaces may be biocompatible with biological fluids such as blood. Overall, this study provides a simple and effective antibacterial coating strategy that can be applied to biomaterials to reduce biofilm-mediated infections.

High Cefuroxime Concentrations and Long Elimination in an Orthopaedic Surgical Deadspace—A Microdialysis Porcine Study

Deadspace is the tissue and bony defect in a surgical wound after closure. This space is presumably poorly perfused favouring bacterial proliferation and biofilm formation. In arthroplasty surgery, an obligate deadspace surrounding the prosthesis is introduced and deadspace management, in combination with obtaining therapeutic prophylactic antibiotic concentrations, is important for limiting the risk of acquiring a periprosthetic joint infection (PJI). This study aimed to investigate cefuroxime distribution to an orthopaedic surgical deadspace in comparison with plasma and bone concentrations during two dosing intervals (8 h × 2). In a setup imitating shoulder arthroplasty surgery, but without insertion of a prosthesis, microdialysis catheters were placed for cefuroxime sampling in a deadspace in the glenohumeral joint and in cancellous bone of the scapular neck in eighteen pigs. Blood samples were collected as a reference. Cefuroxime was administered according to weight (20 mg/kg). The primary endpoint was time above the cefuroxime minimal inhibitory concentration of the free fraction of cefuroxime for Staphylococcus aureus (fT > MIC (4 μg/mL)). During the two dosing intervals, mean fT > MIC (4 μg/mL) was significantly longer in deadspace (605 min) compared with plasma (284 min) and bone (334 min). For deadspace, the mean time to reach 4 μg/mL was prolonged from the first dosing interval (8 min) to the second dosing interval (21 min), while the peak drug concentration was lower and half-life was longer in the second dosing interval. In conclusion, weight-adjusted cefuroxime fT > MIC (4 μg/mL) and elimination from the deadspace was longer in comparison to plasma and bone. Our results suggest a deadspace consolidation and a longer diffusions distance, resulting in a low cefuroxime turn-over. Based on theoretical targets, cefuroxime appears to be an appropriate prophylactic drug for the prevention of PJI.

Antibiotic prophylaxis as a quality of care indicator: does it help in the fight against surgical site infections following fragility hip fractures?

INTRODUCTION

Fragility hip fractures are associated with increased morbidity, mortality, and costs. To improve patient care, quality indicator programs were introduced. Yet, the efficacy of these programs and specific quality indicators are questioned. We aimed to determine whether defining prophylactic pre-surgical antibiotic treatment as a quality indicator affected hip fracture outcomes.

MATERIALS AND METHODS

A retrospective study comparing consecutive patients, 65 years and older, who were operated for fragility hip fractures between 01/01/2011 and 30/06/2016, before and after the prophylactic pre-surgical antibiotic treatment quality indicator, which was introduced in 01/2014. Primary outcomes were 1-year surgical site infections (SSI). Secondary outcomes were meeting the quality index and mortality rates, either within a hospital or during the first post-operative year.

RESULTS

904 patients, ages 82.5 ± 7.2 years were operated for fragility hip fractures. 403 patients presented before the antibiotic prophylaxis quality indicator, and 501 following its administration. Patients demographics were comparable. In the pre-quality indicator period, documentation of prophylactic antibiotic treatment was lacking. Only 19.6% had a record for antibiotic administration in their surgical records and for merely 10.4% the type of antibiotic was stated. However, in the post-quality indicator period, 97.0% of patients had a registered prophylactic antibiotic regimen in the hour preceding the surgical incision (p  < 0.001). Post-operative SSI rates were equivalent, and as were in-hospital infections, mortality and recurrent hospitalizations CONCLUSIONS: The introduction of the pre-operative antibiotic treatment quality indicator increased the documentation of antibiotic administration yet failed to influence the incidence of post-operative orthopaedic and medical infections in fragility hip fracture patients.

Understanding Penicillin Allergy, Cross-reactivity, and Antibiotic Selection in the Preoperative Setting

Penicillin allergies are reported by 8% to 15% of the US population, but up to 95% of these allergies do not correspond to a true allergy when tested. Recent studies have demonstrated that having a penicillin allergy label (PAL) results in a 50% increased odds of surgical site infection among patients reporting a penicillin allergy entirely attributable to the use of a beta-lactam alternative antibiotic (primarily clindamycin or vancomycin). This study provides a review of the prevalence of PAL, the cross-reactivity with cefazolin, immunogenic components of cefazolin and penicillin, and current guidelines for preoperative antibiotic selection in patients with PALs. On understanding these principles, a new set of guidelines and a risk stratification tool are proposed for assessing allergies and determining appropriate antibiotic choice, dosage, and timing in the orthopaedic preoperative setting.

Weight-based cefuroxime dosing provides comparable orthopedic target tissue concentrations between weight groups - a microdialysis porcine study

Antibiotic prophylaxis is a key element in prevention of surgical site infections. For the majority of orthopedic procedures, antibiotic administration follows fixed dosing regimens irrespective of weight. However, this may result in insufficient antibiotic target tissue concentrations and higher risk of surgical site infections in obese individuals. The aim of this study was to investigate the effect of weight-based cefuroxime dosing on plasma and target tissue concentrations. Eighteen female pigs were allocated into three groups differentiated by weight: 53-57 kg, 73-77 kg, and 93-97 kg. Microdialysis catheters were placed for continuous sampling in bone, muscle, and subcutaneous tissue during an 8h sampling interval. Blood samples were collected as reference. Cefuroxime was administered intravenously as a bolus according to weight (20 mg/kg). The primary endpoint was the time above the cefuroxime minimal inhibitory concentration for Staphylococcus aureus (T > MIC (4 μg/mL)). Comparable target tissue T > MICs (4 μg/mL) were found between weight groups. Mean T > MIC ranged between 116-137 min for plasma, 118-154 min for bone, 109-146 min for the skeletal muscle, and 117-165 min for subcutaneous tissue across the groups. Weight-based cefuroxime (20 mg/kg) dosing approach provides comparable perioperative plasma and target tissue T > MIC (4 μg/mL) in animals between 50-100 kg body weight, and thus a comparable prophylaxis of surgical site infections.

Arthroscopic rotator cuff repair without antibiotic prophylaxis does not increase the infection rate

PURPOSE

Rotator cuff repair is a commonly performed shoulder procedure. In the past 20 years, there has been a shift from mini-open towards arthroscopic repair, and many units exclusively use arthroscopic techniques for rotator cuff surgery. The aim of this study was to find out whether withholding antibiotics had any effect on the infection rate in patients undergoing arthroscopic rotator cuff repair.

METHODS

A retrospective analysis of 336 consecutive patients with an arthroscopic rotator cuff repair (RCR) and a minimum 2-year follow-up was performed. The control group received prophylactic antibiotics (controls) and the cases of interest did not receive perioperative antibiotics. A power analysis was performed according to literature regarding infection proportions. The primary outcome was an infection (superficial or deep) in the operated shoulder.

RESULTS

There were 336 patients who underwent a RCR. Two-hundred-and-twelve in the control group and 124 in the non-antibiotic group. Average ages were 57.3 ± 12.5 and 56.8 ± 13.2 years in each group, respectively. The follow-up times ranged from 24 to 76 months. Equipment used and surgical techniques were identical, only operating times were statistically different between the groups (control 77.2 ± 41.3 min versus no antibiotic cases 52.9 ± 16.7 min) (p = 0.000009). There was no recorded infection in either group.

CONCLUSION

Infection following arthroscopic surgery is uncommon. Small incisions, constant lavage with saline, minimal hardware insertion and short operating times all combine to minimise the risks. Current results point towards no detriment in withholding prophylactic antibiotics in low-risk patients undergoing routine rotator cuff repair surgery. Therefore, judicious use of prophylactic antibiotics in patients undergoing this procedure is advocated to prevent potential harm to those it is administered to.

LEVEL OF EVIDENCE

Level III.

Effects of tourniquet inflation on peri- and postoperative cefuroxime concentrations in bone and tissue

Background and purpose - Tourniquet is widely used in orthopedic surgery to reduce intraoperative bleeding and improve visualization. We evaluated the effect of tourniquet application on peri- and postoperative cefuroxime concentrations in subcutaneous tissue, skeletal muscle, calcaneal cancellous bone, and plasma. The primary endpoint was the time for which the free cefuroxime concentration was maintained above the clinical breakpoint minimal inhibitory concentration (T > MIC) for Staphylococcus aureus (4 µg/mL).Patients and methods - 10 patients scheduled for hallux valgus or hallux rigidus surgery were included. Microdialysis catheters were placed for sampling of cefuroxime concentrations bilaterally in subcutaneous tissue, skeletal muscle, and calcaneal cancellous bone. A tourniquet was applied on the thigh of the leg scheduled for surgery (tourniquet duration time [range]: 65 minutes [58-77]). Cefuroxime (1.5 g) was administered intravenously 15 minutes prior to tourniquet inflation, followed by a second dose 6 hours later. Dialysates and venous blood samples were collected for 12 hours.Results - A cefuroxime concentration of 4 µg/mL was reached within 23 minutes in all compartments and patients. For cefuroxime the T > MIC (4 µg/mL) ranged between 4.8 and 5.4 hours across compartments, with similar results for the tourniquet and non-tourniquet leg. Comparable T > MIC and penetration ratios were found for the first and second dosing intervals.Interpretation - Administration of cefuroxime (1.5 g) 15 minutes prior to tourniquet inflation is safe in order to achieve tissue concentrations above 4 µg/mL throughout surgery. A tourniquet application time of approximately 1 hour did not affect the cefuroxime tissue penetration in the following dosing interval.

Evolution in the Acute Management of Open Fracture Treatment? Part 1

INTRODUCTION

Despite decades of advancement in wound debridement, prophylactic antibiotic therapy, fracture stabilization, and soft tissue reconstruction, infection remains a serious complication after open fracture. Inconclusive historical data and new challenges with resistant organisms and antimicrobial stewardship having created a difficult environment within which to develop sound, evidence-based treatment protocols that can be applied universally. The first part of this 2-part series will synthesize the historical perspective along with the current concepts surrounding bacteriology and antibiotic use/stewardship. Part 2 will analyze and summarize the current literature regarding the management of open fracture and prevention of subsequent infection.Numerous authors from Hippocrates to Larrey noted that superior results were obtained with an early aggressive debridement of necrotic tissue after wounding.1-7 Historically, the usual outcome after open fracture was infection, sepsis, amputation, and death before the introduction of antibiotics.8-11 As recently as the first half of the 20th century, surgeons argued that if an appropriate debridement was performed, antibiotics were not necessary and advocated against their routine use over concern for resistant organisms.The current period of open fracture treatment (starting in the 1970s) heralded a more scientific era with critical evaluation of antibiotics, surgical debridement, and the development of standardized evidence-based protocols. This era began with 3 classic articles by Patzakis and Gustilo that, to this day, remain central to the discussion of infection prevention after open fractures.12-14.

LEVEL OF EVIDENCE

Therapeutic Level V. See Instructions for Authors for a Complete description of levels of evidence.

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.

Infection after Open Long Bone Fractures: Can we Improve on Prophylaxis?

INTRODUCTION

Current standards recommend antibiotic prophylaxis administered after open fracture injury. The purpose of this study was to assess culture results in patients with open fracture-associated infections, hypothesizing that cultures obtained do not vary by Gustilo-Anderson (GA) classification.

METHODS

We examined cultured bacterial species from patients with open long bone fractures that underwent irrigation and debridement at a Level 1 trauma center (2008-2016), evaluating our current and two hypothetical antibiotic protocols to assess whether they provided appropriate coverage. The antibiotic protocols included protocols 1 (cefazolin, with gentamicin added for type III fractures), 2 (vancomycin and cefepime) and 3 (ceftriaxone).

RESULTS

GA classification was not associated with bacterial gram stain (P = 0.161), nor was it predictive of mono- versus polymicrobial infection (P = 0.094). Of 42 culture-positive infections, 31 were type III and 11 were type I or II fractures. 27% of the infections for type I or II fractures were caused by organisms targeted by protocol 1 (OR 0.18, 95% CI 0.04-0.82; P = 0.027). There was no difference in coverage by fracture type among protocol 2 (P = 0.771) or protocol 3 (P = 0.891). For type III fractures, protocol 2 provided 94% appropriate coverage compared to 68% and 61% coverage by protocols 1 and 3, respectively.

CONCLUSION

For open fractures complicated by infection, isolated bacterial organisms do not correlate with GA open fracture classification, suggesting that hypothetical protocol 2 should be used for all fracture types. Protocol 2's broad coverage, across all GA fracture types, may prevent infection by organisms not covered by current antibiotic prophylaxis.

Perioperative Management of Antirheumatic Medications in Patients with RA and SLE Undergoing Elective Foot and Ankle Surgery: A Critical Analysis Review

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Recent literature has shown that continued use rather than discontinuation of various antirheumatic agents throughout the perioperative period may present an opportunity to mitigate the risks of elective surgery.

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For patients with rheumatoid arthritis and systemic lupus erythematosus, perioperative management of medication weighs the risk of infection against the risk of disease flare when immunosuppressive medications are withheld.

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Broadly speaking, current evidence, although limited in quality, supports perioperative continuation of disease-modifying antirheumatic drugs, whereas biologic drugs should be withheld perioperatively, based on the dosing interval of the specific drug.

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For any withheld biologic drug, it is generally safe to restart these medications approximately 2 weeks after surgery, once the wound shows evidence of healing, all sutures and staples have been removed, and there is no clinical evidence of infection. The focus of this recommendation applies to the optimization of wound-healing, not bone-healing.

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In most cases, the usual daily dose of glucocorticoids is administered in the perioperative period rather than administering "stress-dose steroids" on the day of surgery.

Antibiotic resistance: still a cause of concern?

Antibiotic resistance remains a global public health concern with significant patient morbidity and tremendous associated health care costs. Drivers of antibiotic resistance are multifaceted and differ between developing and developed countries. Under evolutionary pressure, microbes acquire antibiotic tolerance through a variety of mechanisms at the cellular level. Patients after orthopaedic trauma are vulnerable to drug-resistant pathogens, particularly after open fractures. Traumatologists practicing appropriate antibiotic prophylaxis and treatment regimens mitigate infection and propagation of antibiotic resistance.

Double-dose cefuroxime concentrations in bone, synovial fluid of the knee joint and subcutaneous adipose tissue-A randomised porcine microdialysis study

This study evaluated target tissue concentrations of double dose cefuroxime administered intravenously as either one 15 min infusion of 3000 mg (Group 1) or two single 15 min infusions of 1500 mg administered 4 h apart (Group 2). Sixteen pigs were randomised into two groups of eight. Cortical and cancellous bone, synovial fluid of the knee joint and subcutaneous adipose tissue concentrations were measured based on sampling via microdialysis. Plasma samples were collected as a reference. Comparison of the groups was based on time with concentrations above relevant minimal inhibitory concentrations (fT>MIC) of 4 μg/mL. The mean time fT>MIC (4 μg/mL) across compartments was longer for Group 2 (280-394 min) than for Group 1 (207-253 min) (p<0.01). Cortical bone showed a tendency towards longer fT>MIC (4 μg/mL) in Group 2 (280 min) than in Group 1 (207 min) (p = 0.053). Within 50 min after administration, the mean concentration of 4 μg/mL was reached in all compartments for both groups. The mean concentrations decreased below 4 μg/mL after approximately 4 h (Group 1) and 3 h (Group 2) from initiation of administration (time zero). During an 8 h interval, double-dose cefuroxime administered as 2 × 1500 mg with a 4 h interval provides longer time above MIC breakpoint for Staphylococcus aureus (4 μg/mL) than a single bolus of 3000 mg cefuroxime. To maintain sufficient tissue concentrations during longer surgeries, re-administration of cefuroxime (1500 mg) should be considered 3 h after the first administration.

Utility of Common Biomarkers for Diagnosing Infection in Nonunion

OBJECTIVES

To evaluate the diagnostic utility of leukocyte count (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) for distinguishing between septic and aseptic nonunions.

DESIGN

A single-gate (cohort) design was used, using 1 set of eligibility criteria applied to a consecutive sample of nonunions.

SETTING

Private quaternary referral center.

PATIENTS/PARTICIPANTS

Inclusion criteria were consecutive patients (≥18 years) with a nonunion requiring surgery that allowed for direct or medullary canal tissue sampling from the nonunion site. The cohort included 204 subjects with 211 nonunions.

INTERVENTION

Blood samples were drawn for laboratory analysis of WBC, ESR, and CRP before surgery.

MAIN OUTCOME MEASUREMENTS

The reference standard used to define infection was the fracture-related infection confirmatory criteria. Measures of diagnostic accuracy were calculated. To assess the additional diagnostic gain of each index lab test while simultaneously considering the others, logistic regression models were fit.

RESULTS

The prevalence of infection was 19% (40 of 211 nonunion sites). The positive likelihood ratios (95% confidence interval) for WBC, ESR, and CRP were 1.07 (0.38-3.02), 1.27 (0.88-1.82) and 1.57 (0.94-2.60), respectively. Multivariable modeling adjusted for the effect of preoperative antibiotics showed that WBC (P = 0.42), ESR (P = 0.48), and CRP (P = 0.23) were not significant predictors of infection.

CONCLUSIONS

In this consecutive sample of 211 nonunions in whom standard clinical practice would be to obtain index lab tests, our findings showed that WBC, ESR, and CRP were not significant predictors of infection.

LEVEL OF EVIDENCE

Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Can Pediatric Orthopaedic Surgery be Done Safely in a Freestanding Ambulatory Surgery Center? Review of 3780 Cases

BACKGROUND

The purpose of this study was to determine the intraoperative and 30-day postoperative complication rates in a large consecutive cohort of pediatric patients who had orthopaedic surgery at a freestanding ambulatory surgery center (ASC). The authors also wanted to identify the rates of same-day, urgent hospital transfers, and 30-day hospital admissions. The authors hypothesized that pediatric orthopaedic procedures at a freestanding ASC can be done safely with a low rate of complications.

METHODS

A retrospective review identified patients aged 17 years or younger who had surgery at a freestanding ASC over a 9-year period. Adverse outcomes were divided into intraoperative complications, postoperative complications, need for the secondary procedure, unexpected hospital admission on the same day of the procedure, and unexpected hospital admission within 30 days of the index procedure. Complications were graded as grade 1, the complication could be treated without additional surgery or hospitalization; grade 2, the complication resulted in an unplanned return to the operating room (OR) or hospital admission; or grade 3, the complication resulted in an unplanned return to the OR or hospitalization with a change in the overall treatment plan.

RESULTS

Adequate follow-up was available for 3780 (86.1%) surgical procedures. Overall, there were 9 (0.24%) intraoperative complications, 2 (0.08%) urgent hospital transfers, 114 (3%) complications, and 16 (0.42%) readmissions. Seven of the 9 intraoperative complications resolved before leaving the OR, and 2 required return to the OR.Neither complications nor hospitalizations correlated with age, race, gender, or length or type of surgery. There was no correlation between the presence of medical comorbidities, body mass index, or American Society of Anesthesiologists score and complication or hospitalization.

CONCLUSIONS

Pediatric orthopaedic surgical procedures can be performed safely in an ASC because of multiple factors that include dedicated surgical teams, single-purpose ORs, and strict preoperative screening criteria. The rates of an emergency hospital transfer, surgical complications, and 30-day readmission, even by stringent criteria, are lower than those reported for outpatient procedures performed in the hospital setting.

LEVEL OF EVIDENCE

Level IV-case series.

Controlling Antibiotic Release from Polymethylmethacrylate Bone Cement

Bone cement is used as a mortar for securing bone implants, as bone void fillers or as spacers in orthopaedic surgery. Antibiotic-loaded bone cements (ALBCs) have been used to prevent and treat prosthetic joint infections by providing a high antibiotic concentration around the implanted prosthesis. High antibiotic concentrations are, on the other hand, often associated with tissue toxicity. Controlling antibiotic release from ALBCS is key to achieving effective infection control and promoting prosthesis integration with the surrounding bone tissue. However, current ALBCs still need significant improvement in regulating antibiotic release. In this review, we first provide a brief introduction to prosthetic joint infections, and the background concepts of therapeutic efficacy and toxicity in antibiotics. We then review the current state of ALBCs and their release characteristics before focusing on the research and development in controlling the antibiotic release and osteo-conductivity/inductivity. We then conclude by a discussion on the need for better in vitro experiment designs such that the release results can be extrapolated to predict better the local antibiotic concentrations in vivo.

Usefulness of prophylactic antibiotics in preventing infection after internal fixation of closed hand fractures

Prophylactic antibiotics (PA) have been shown to be ineffective in reducing the incidence of surgical site infection (SSI) in clean wounds associated with elective surgery of the hand. Routine administration of PA for internal fixation of hand fractures is a subject that has been scarcely studied. We hypothesized that PA do not reduce SSI incidence in fixation of closed hand fractures. We did a retrospective comparative study in patients who underwent open or closed reduction and internal fixation of a hand and carpus fracture. Patient demographics, past medical history, fracture characteristics and the type of internal fixation used were extracted from our electronic archives. Follow-up period lasted for 1 year, during which any form of clinically evident SSI, such as pus formation, wound dehiscence and positive bacterial culture was documented. A total of 107 patients met the inclusion criteria, 63 in the control group and 44 in the test group. The overall infection rate was 6.5%. All infections (3 in the control group and 4 in the test group) were pin-tract infections that resolved completely after pin extraction. Our study did not find significant differences between groups (P = 0.442). No specific fracture pattern was associated with increased total infection rate (p = 0.898). In this study, we found no support for routine administration of PA prior to internal fixation of closed fractures of the hand and carpus. PA should still be administered in selected patients, such as those with decreased immunity or open fractures. Further large-scale research is needed to establish proper guidelines, to reduce the adverse effects of antibiotic treatment.

Effect of Postoperative Oral Antibiotics on Infections and Wound Healing Following Foot and Ankle Surgery

BACKGROUND

There is controversy regarding the effectiveness of postoperative antibiotics to prevent wound infection. Some surgeons still use a routine postoperative oral antibiotic regimen. The purpose of this study was to review a series of cases and document statistically any difference in infection rates and whether routine postoperative antibiotics in foot and ankle surgery are justified.

METHODS

A retrospective chart review of 649 patients was performed who underwent elective foot and ankle surgery. Six hundred thirty-one patient charts were included in the final analysis. Evaluated were patients who did and did not receive postoperative oral antibiotics in order to identify whether a difference in infection rate or wound healing occurred. The study also evaluated risk factors for developing infection following foot and ankle surgery.

RESULTS

The number of infections in patients receiving postoperative oral antibiotics was 6 (3%), while the number of infections in those who did not receive postoperative oral antibiotics was 10 (2%) (P = .597). The difference of deep versus superficial infections and delays in wound healing between the 2 groups was not statistically significant. Patients who developed infections were older and had a higher prevalence of hypertension, a history of neoplasm, and a greater American Society of Anesthesiologists Classification of Physical Health.

CONCLUSION

This study suggests that routine use of postoperative antibiotics in foot and ankle surgery does not affect wound complications or infection rates. Additionally, patients who are older and those with multiple medical problems may be at higher risk for developing postoperative infection following foot and ankle surgeries.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Nomogram prediction of surgical site infection of HIV-infected patients following orthopedic surgery: a retrospective study

BACKGROUND

Surgical site infection (SSI) is a devastating complication of orthopedic surgery, related with increased morbidity and mortality. This study was performed with the aim to compare the SSI rate in human immunodeficiency virus HIV-positive patients, to identify other risk factors for SSI and to establish a nomogram model to predict the risk of SSI.

METHODS

A total of 101 HIV-positive individuals following orthopedic surgery patients admitted to Beijing Ditan Hospital. Their characteristics were gathered. The univariate and multiple logistic regression analysis were performed to explore the risk factors of SSI. And the Nomogram prediction model was constructed and verified.

RESULTS

The independent predictive factors of SSI included CD4 (Odds ratio [OR], 0.041; P = 0.040), erythrocyte sedimentation rate (ESR) (OR, 89.773; P = 0.030), and procalcitonin (PCT) (OR, 220.746; P = 0.006). The scoring nomogram model was as follows: Logit (SSI) = - 2.63589-0.00314*CD4 < 430.75 = 1) + 0.04695*(ESR < 17.46 = 1) + 2.93694*(PCT < 0.22 = 1). The area under the Receiver Operating Characteristic (ROC) curve was 0.946. The cutoff score was - 2.1026 with a sensitivity of 93.33% and a specificity of 84.88%.

CONCLUSIONS

CD4, ESR, PCT might affect the occurrence of SSI after orthopedic surgery. The nomogram model constructed in this study is helpful for predicting the probability of SSI.

Timing of Antimicrobial Prophylaxis and Tourniquet Inflation: A Randomized Controlled Microdialysis Study

BACKGROUND

Tourniquets are widely used during extremity surgery. In order to prevent surgical site infection, correct timing of antimicrobial prophylaxis and tourniquet inflation is important. We aimed to evaluate the time for which the free drug concentration of cefuroxime is maintained above the minimum inhibitory concentration (t > MIC) in porcine subcutaneous adipose tissue and calcaneal cancellous bone during 3 clinically relevant tourniquet application scenarios.

METHODS

Twenty-four female Danish Landrace pigs were included. Microdialysis catheters were placed bilaterally for sampling of cefuroxime concentrations in calcaneal cancellous bone and subcutaneous adipose tissue, and a tourniquet was applied to a randomly picked leg of each pig. Subsequently, the pigs were randomized into 3 groups to receive 1.5 g of cefuroxime by intravenous injection 15 minutes prior to tourniquet inflation (Group A), 45 minutes prior to tourniquet inflation (Group B), and at the time of tourniquet release (Group C). The tourniquet duration was 90 minutes in all groups. Dialysates and venous blood samples were collected for 8 hours after cefuroxime administration. Cefuroxime and various ischemic marker concentrations were quantified.

RESULTS

Cefuroxime concentrations were maintained above the clinical breakpoint MIC for Staphylococcus aureus (4 µg/mL) in calcaneal cancellous bone and subcutaneous adipose tissue throughout the 90-minute tourniquet duration in Groups A and B. Cefuroxime administration at the time of tourniquet release (Group C) resulted in concentrations of >4 µg/mL for approximately of 3.5 hours in the tissues on the tourniquet side. Furthermore, tourniquet application induced ischemia (increased lactate:pyruvate ratio) and cell damage (increased glycerol) in subcutaneous adipose tissue and calcaneal cancellous bone. Tissue ischemia was sustained for 2.5 hours after tourniquet release in calcaneal cancellous bone.

CONCLUSIONS

Administration of cefuroxime (1.5 g) in the 15 to 45-minute window prior to tourniquet inflation resulted in sufficient concentrations in calcaneal cancellous bone and subcutaneous adipose tissue throughout the 90-minute tourniquet application. Furthermore, tourniquet-induced tissue ischemia fully resolved 2.5 hours after tourniquet release.

CLINICAL RELEVANCE

Cefuroxime administration 15 to 45 minutes prior to tourniquet inflation seems to be a safe window. If the goal is to maintain postoperative cefuroxime concentrations above relevant MIC values, our results suggest that a second dose of cefuroxime should be administered at the time of tourniquet release.

Characteristics of Antibiotic Prophylaxis and Risk of Surgical Site Infections in Primary Total Hip and Knee Arthroplasty

BACKGROUND

Despite numerous antibiotic prophylaxis options for total hip arthroplasty (THA) and total knee arthroplasty (TKA), an assessment of practice patterns and comparative effectiveness is lacking. We aimed to characterize antibiotic utilization patterns and associations with infection risk and hypothesized differences in infection risk based on regimen.

METHODS

A retrospective cohort study was performed using data from 436,724 THA and 862,918 TKA (Premier Healthcare Database; 2006-2016). Main exposures were antibiotic type and duration: day of surgery only (day 0) or through postoperative day 1 (day 1). The primary outcome was surgical site infection (SSI) <30 days postoperation. Mixed-effect models measured associations between prophylaxis regimen and SSI as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

SSI prevalence was 0.21% (n = 914) for THA and 0.22% (n = 1914) for TKA. Among THA procedures, the most commonly used antibiotics were cefazolin (74.1%), vancomycin (8.4%), "other" antibiotic combinations (7.1%), vancomycin + cefazolin (5.1%), and clindamycin (3.3%). Here, 51.8% received prophylaxis on day 0 only, whereas 48.2% received prophylaxis through day 1. Similar patterns existed for TKA. Relative to cefazolin, higher SSI odds were seen with vancomycin (OR = 1.36; CI 1.09-1.71) in THA and with vancomycin (OR = 1.29; CI = 1.10-1.52), vancomycin + cefazolin (OR = 1.35; CI = 1.12-1.64), clindamycin (OR = 1.38; CI = 1.11-1.71), and "other" antibiotic combinations (OR = 1.28; CI = 1.07-1.53) in TKA. Prophylaxis duration did not alter SSI odds. Results were corroborated in sensitivity analyses.

CONCLUSION

Antibiotic prophylaxis regimens other than cefazolin were associated with increased SSI risk among THA/TKA patients. These findings emphasize a modifiable intervention to mitigate infection risk.

Pharmacokinetics of double-dose cefuroxime in porcine intervertebral disc and vertebral cancellous bone-a randomized microdialysis study

BACKGROUND CONTEXT

Postoperative pyogenic spondylodiscitis is associated with prolonged antimicrobial therapy and high relapse rates. Cefuroxime is a time-dependent antimicrobial widely used for intravenous perioperative prophylaxis in spine surgery. A previous study has indicated that a single dose of cefuroxime (1.5 g) provides insufficient spine tissue concentrations for spine procedures lasting more than 2 to 3 hours.

PURPOSE

To evaluate the time with concentrations above relevant minimal inhibitory concentrations (T>MIC) in plasma, subcutaneous adipose tissue, vertebral cancellous bone, and intervertebral disc after a twofold increase of the standard dosage of 1.5 g cefuroxime given as one double dose (1×3 g) or two single doses (2×1.5 g) with a four-hour interval.

METHODS

Sixteen pigs were randomized into two groups: Group 1 received one double dose of cefuroxime (1×3 g) as an intravenous bolus and Group 2 received two single doses of cefuroxime (2×1.5 g) as an intravenous bolus with a four-hour interval. Cefuroxime measurements were obtained from plasma, subcutaneous adipose tissue, vertebral cancellous bone, and intervertebral disc for eight hours thereafter. Microdialysis was applied for sampling in solid tissues. The cefuroxime concentrations were determined using ultra-high performance liquid chromatography. This work was supported by grants from the Health Research Foundation of Central Denmark Region (Level E). The funding source did not play any role in the investigation.

RESULTS

The time with concentrations above the Staphylococcus aureus clinical breakpoint minimal inhibitory concentration of 4 μg/mL was higher in all compartments for Group 2 compared to Group 1. The mean T>MIC (4 μg/mL) in all compartments ranged between 47% and 67% for Group 1 and 72% and 92% for Group 2. Furthermore, a delayed tissue penetration into all tissues for both groups was demonstrated.

CONCLUSIONS

This study suggests that cefuroxime should be given at least 45 minutes prior to spine procedures and as two single doses at a maximum interval of four hours for extended spine procedures. Clinical studies verifying these results are warranted.

CLINICAL SIGNIFICANCE

Administering cefuroxime as two single doses (2×1.5 g) with a four-hour interval compared to one double dose (1×3 g) resulted in higher T>MIC. Furthermore, we found delayed and incomplete cefuroxime tissue penetration.

Antibiotic prescription patterns for treating dental infections in children among general and pediatric dentists in teaching institutions of Karachi, Pakistan

BACKGROUND

Antibiotics are regularly prescribed by dental professionals in their practice, for the purpose of dental treatment as well as for the prevention of infection. The inappropriate use of antibiotics is a significant factor in the rise of antibiotic resistance. There is an immediate need for the advancement of prescribing guidelines and instructive polices to encourage the rational and appropriate utilization of medications especially antibiotics in dentistry.

OBJECTIVE

The aim of this study was to identify the frequency of antibiotic prescription for treating dental infections in children among dentists in teaching institutions of Karachi, Pakistan and whether they are adhering to the prescribed international guidelines.

METHODS

A cross-sectional study was conducted in three private and two public colleges of Karachi. After taking written informed consent and checking the inclusion criteria, a total of 380 participants were interviewed using a pre-designed validated questionnaire which included demographic profile and clinical case scenarios. Data were entered and analyzed on SPSS version 20. Inferential analysis was performed using chi-square test. The significance level was set at 0.05.

RESULTS

Of the 380 subjects, a majority (71.3%) treated 15 or less children per month (n = 271) while 28.7% of dentists (n = 109) treated more than 15 children per month. Overall adherence to American Academy of Pediatric Dentistry guidelines was low from 26.1% to 44.2%. The difference between adherence of dentists with low and high volume of pediatric patients was significantly different for case scenarios 1, 3, 4 and 5 (p<0.001 for all) where dentists who treated 15 or less children per month were more likely to be adherent to standard antibiotic prescription guidelines than those who treated more than 15 children per month.

CONCLUSIONS

This study shows that majority of dentists, particularly dentists with high volume of pediatric patients lacked adherence to professional guidelines for prescribing antibiotics for treating dental infection in children. There seem to be a lack of harmony between the recommended professional guidelines and the antibiotic prescribing pattern of dentists. Regular updates and continuing medical education for the health professionals regarding comprehensible and specific professional guidelines may lead to improved adherence of antibiotics prescription amongst dentists.

Controversies in Perioperative Antimicrobial Prophylaxis

Although clinical guidelines for antibiotic prophylaxis across a wide array of surgical procedures have been proposed by multidisciplinary groups of physicians and pharmacists, clinicians often deviate from recommendations. This is particularly true when recommendations are based on weak data or expert opinion. The goal of this review is to highlight certain common but controversial topics in perioperative prophylaxis and to focus on the data that does exist for the recommendations being made.

Chitosan-calcium phosphate composite scaffolds for control of post-operative osteomyelitis: Fabrication, characterization, and in vitro-in vivo evaluation

Osteomyelitis is a progressive inflammatory disease requiring prolonged systemic treatment with high antibiotic doses, and is very challenging to be treated. The use of locally applied antibiotics loaded on a biodegradable carrier at surgery sites is hypothesized to prevent post-operative osteomyelitis, while providing site-specific drug release. In this work, chitosan-based calcium phosphate composites were prepared and loaded with moxifloxacin hydrochloride. The in-situ formation of calcium phosphates within the composite was experimentally confirmed by Fourier transform infra-red spectroscopy, X-ray powder diffraction, and scanning electron microscopy. Results showed that the composites provided complete drug release over three days, and the selected composite formulation induced differentiation and proliferation of osteoblasts, while reducing bacterial count, inflammation and intra-medullary fibrosis in bone tissue specimens of osteomyelitis-induced animal model. Hence, we can conclude that the in situ prepared antibiotic-loaded calcium phosphate chitosan composite is promising in preventing post-operative osteomyelitis, and is worthy of clinical experimentation.

Antibiotic Cement in Arthroplasty: A Meta-analysis of Randomized Controlled Trials

Introduction Periprosthetic joint infection (PJI) following arthroplasty surgery is a devastating complication. Antibiotic cement has been proposed as a way to reduce PJI rates. The aim of this systematic review and meta-analysis was to review all of the available randomized controlled trial (RCT) evidence on the use of antibiotic cement in arthroplasty. Methods PubMed, MEDLINE, and Embase were searched. All records were screened in triplicate. Eligible RCTs were included. Data regarding study characteristics, patient demographics, and rates of superficial and deep infection were collected. The risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool 2.0. Results Five RCTs were included (n = 4,397). Four studies compared antibiotic cement to plain cement while one study compared high-dose dual-antibiotic (HDDA) cement to low-dose single-antibiotic (LDSA) cement. The mean age of included patients was 76.4 years (range: 68-83). There was no significant difference in superficial infection rates between antibiotic and plain cement (odds ratio (OR): 1.33, 95% Confidence Interval (CI): 0.77-2.30, p = 0.3). There was a large but non-significant reduction in deep infection rates for antibiotic cement (OR: 0.20, 95%CI: 0.03-1.32, p = 0.09). There was a significantly lower rate of infection with HDDA as compared to LDSA (OR: 0.31, 95% CI: 0.09-0.88, p = 0.041). Conclusion The available evidence from RCTs reveals a potential benefit for antibiotic cement in arthroplasty surgery, though this difference is non-significant and highly imprecise. Furthermore, HDDA cement was significantly more effective than LDSA cement. There is a need for large, pragmatic trials on this topic.

Surgical applications of intracorporal tissue adhesive agents: current evidence and future development

Introduction: Traditional mechanical closure techniques pose many challenges including the risk of infection, tissue reaction, and injury to both patients and clinicians. There is an urgent need to develop tissue adhesive agents to reform closure technique. This review examined a variety of tissue adhesive agents available in the market in an attempt to gain a better understanding of intracorporal tissue adhesive agents as medical devices.Areas covered: Fundamental principles and clinical determinants of the tissue adhesives were summarized. The available tissue adhesives for intracorporal use and their relevant clinical evidence were then presented. Lastly, the perspective of future development for intracorporal tissue adhesive were discussed. Clinical evidence shows current agents are efficacious as adjunctive measures to mechanical closure and these agents have been trialed outside of clinical indications with varied results.Expert opinion: Despite some advancements in the development of tissue adhesives, there is still a demand to develop novel technologies in order to address unmet clinical needs, including low tensile strength in wet conditions, non-controllable polimerization and sub-optimal biocompatibility. Research trends focus on producing novel adhesive agents to remit these challenges. Examples include the development of biomimetic adhesives, externally activated adhesives, and multiple crosslinking strategies. Economic feasibility and biosafety are limiting factors for clinical implementation.

Use of Intraoperative Tranexamic Acid and Wound Complications in Spine Surgery: A Retrospective Cohort Study

Study Design

A retrospective cohort study.

Purpose

This study aims to examine the effect of tranexamic acid (TXA) on postoperative wound healing in spine surgery.

Overview of Literature

TXA (Cyklokapron, Hexakapron) is a widely used anti-fibrinolytic drug that is shown to be effective in mitigating hemorrhage during and after surgery by competitively blocking plasminogen in fibrinolytic cascade. Plasminogen also plays a role in inflammatory and infectious diseases. The modulation of this role by TXA may influence the development of postoperative infectious complications.

Methods

We collected and reviewed the charts of 110 patients who underwent spine surgery at our academic center. We used multivariate regression analysis to assess the factors affecting surgical site infection (SSI).

Results

Of the 110 patients included in this study, 21 patients (19%) were categorized as having postoperative wound complications, 16 patients (14%) had deep or superficial wound infection, and five patients (4%) had wound dehiscence. Patients with a higher surgical invasiveness index score, longer surgeries, and older patients were found to be at risk for wound complications. TXA was determined not to be a direct risk factor for wound healing complications and SSIs.

Conclusions

We found no risk of wound healing complications and SSI directly attributable to preoperative and intraoperative treatment with TXA in spine surgeries.