Infection In Open Fractures Research Articles

Retrospective Study on the Microbial Drug Resistance Profile and Predictive Risk Factors in Early Infection of Open Fractures

Introduction: This study was conducted to evaluate the susceptibility of microorganisms involved in early infection of open fractures in orthopaedics to current prophylactic antibiotics practice and determine the association of various parameters related to the causative organism, patient, injury and management to the resistance of such microorganisms. Methods: This is a retrospective study that reviewed cases collected from the surgical operations record from January 2015 to December 2017 in Hospital Tengku Ampuan Afzan, Kuantan. A total of 179 cases were collected with 110 cases fulfilling the proposed inclusion / exclusion criteria. They all underwent routine debridement followed by culture and sensitivity. Previous clinical records were traced to identify the various risk factors for infection and evaluate these against the resistance of the microorganisms to prophylactic antimicrobial drugs. Results: Admission to the intensive care unit, blood transfusion, antibiotic regime and duration, fracture grade, injury severity score and duration of admission were all significantly associated with resistance of microorganism. The study also demonstrated the predominance of Gram-negative microorganisms constituting 65.9% of isolates. Gramnegative microorganisms were seen more in higher fracture grades and Injury Severity Scale, and longer duration of admission and antibiotic treatment. The overall susceptibility of microorganisms to antibiotics was also demonstrated with up to 68.6% resistance to cefuroxime and 36.9% to Gentamicin. Staphylococcus aureus and MRSA were the commonest Gram-positive organisms while Pseudomonas and Acinetobacter spp. the commonest Gram-negatives. Conclusion: Admission to Intensive Care Unit, blood transfusion, antibiotic regime and duration, fracture grade, injury severity score and duration of antibiotics have a significant positive predictive value to the development of resistance of microorganisms. The shift to predominantly Gram-negative microorganisms indicate an urgency to modify management of open fracture to achieve optimal results. This will also prevent the emergence of new multi-drug resistance microorganism which is already a worldwide public health problem.

Impact of duration of perioperative antibiotic prophylaxis on development of fracture-related infection in open fractures.

Infection is a common complication of open fractures potentially leading to nonunion, functional loss, and even amputation. Perioperative antibiotic prophylaxis (PAP) is standard practice for infection prevention in the management of open fractures. However, optimal duration of PAP remains controversial. The objectives were to assess whether PAP duration is independently associated with infection in open fractures and if administration of PAP beyond the commonly-recommended limit of 72h has any effect on the infection rate. Over a 14-year period from 2003 to 2017, 530 skeletally-mature patients with operatively-treated, non-pathologic, long-bone open fractures were treated at one institution. Twenty-eight patients were excluded because of death or loss to follow-up and the remaining 502 patients (with 559 open fractures) who completed a 24-month follow-up were included in this retrospective study. The outcome was fracture-related infection (FRI), defined by the criteria of a recent consensus definition. A logistic generalized estimating equations regression model was conducted, including PAP duration and variables selected by a least absolute shrinkage and selection operator (LASSO) method, to assess the association between PAP duration and FRI. Propensity score analysis using a 72-h cut-off was performed to further cope with confounding. PAP duration, adjusted for the LASSO selected predictors, was independently associated with FRI (OR: 1.11 [95%CI, 1.04-1.19] for every one-day increase in PAP duration, p = 0.003). PAP duration longer than 72h did not significantly increase the odds for FRI compared to shorter durations (p = 0.06, analysis adjusted for propensity score). This study found no evidence that administration of prophylactic antibiotics beyond 72h in patients with long-bone open fractures is warranted. Analyses adjusted for known confounders even revealed a higher risk for FRI for longer PAP. However, this effect cannot necessarily be considered as causal and further research is needed.

Delay of Antibiotic Administration Greater than 2 Hours Predicts Surgical Site Infection in Open Fractures

AimsAntibiotic administration, severity of injury, and debridement are associated with surgical site infection (SSI) after internal fixation of open fractures. We sought to validate a time-dependent treatment effect of antibiotic administration. PatientsConsecutive open fracture patients at a level 1 trauma center with minimum 30-day follow-up were identified from an orthopaedic registry from 2013-2017. MethodsThe primary endpoint was SSI within 90 days. A threshold time to antibiotic administration associated with SSI was ascertained by receiver-operator analysis. A Cox proportional hazards model adjusted for age, smoking, and drug use determined the treatment effect of antibiotic administration within the threshold period. ResultsTen percent of 230 patients developed a SSI. There was a trend for patients who did not develop an SSI to receive antibiotics earlier than those who did develop an SSI (61 minutes, IQR 33-107 vs 83 minutes, IQR 40-186), p=0.053). Intravenous antibiotic administration after 120 minutes of presentation of an open fracture to emergency department was significantly associated with a 2.4 increased hazard of surgical site infection (p=0.036) within 90 days. ConclusionAntibiotic administration greater than 120 minutes after ED presentation of an open fracture was associated with an increased risk of SSI.

Comparison of bacteria isolated from open fractures following debridement and subsequent infection

BackgroundOne of the major objectives for the management of open fractures is to prevent bone and soft tissue infection. Here, we identified species and drug sensitivities of bacterial isolates recovered during open fracture debridement and after infection and compared the results between the two time points. MethodsA total of 61 hospitalized patients with open fractures who developed post-operative wound infection between October 2016 and December 2017 were included in this study. The cohort included 43 males and 18 females aged between 4 and 72 years. Patients were admitted to hospital 1–14 h after injury. Samples were collected after debridement and after infection and submitted for bacterial culture. Resulting isolates were identified using a VITEK 2 Bacterial Identification System and tested for drug sensitivity using the disc diffusion method. Results from the two time points were then compared. ResultsThe positive bacterial culture rate following debridement was relatively low (14/61, 22.9%). In addition, bacteria cultured after debridement were generally inconsistent with those cultured after wound infection, with a concordance rate of only 3.3% (2/61). Gram-negative bacteria accounted for 91.3% (63/69) of isolates recovered from wound infections following surgery, among which Acinetobacter baumannii was baumannii was the predominant pathogen, accounting for 49.3% (42/69) of all isolates. Overall, 60.8% (42/69) of postoperative infections were caused by multi-drug resistant bacteria, with A. baumannii isolates accounting for 80.9% (34/42) of these cases. Rates of cefoperazone/sulbactam resistance were relatively low among the isolates (15/34, 44.1%), and most isolates showed a sensitive or intermediate resistance phenotype. ConclusionsResults of bacterial culture after debridement could not predict pathogenic bacteria causing postoperative infection. Therefore, we propose that open fracture infections are predominantly nosocomial and are mainly caused by multidrug-resistant Gram-negative bacteria. Further attention should be paid to the control of these pathogens in clinical settings.

The Novel Role of Healing from Bacterial Infections of Lower Limb Open Fractures by X-Ray Exposure.

Objective To confirm the role of X-ray exposure in treating infected wound fractures at the lower limb and determine X-ray exposure times. Methods Fifty-one wound swabs were collected from patients with infected open fractures at the lower limb with grade II, IIIA, B, and C according to the Gustilo and Anderson classification system and then cultured. The bacterial isolates were identified by biochemical tests and the VITEK-2 System and tested against several antibiotics. The X-ray exposure was done for open fractures by radiography (at kV133 and 5 milliambers). Results The higher isolation rate was recorded for Staphylococcus aureus with 21 (41.2%) isolates, and most of them (20, 95.2%) were isolated from grade II fractures. The isolation rate of Gram-negative bacteria was 25.5% for Escherichia coli with 13 isolates, 19.6% for Pseudomonas aeruginosa with 10 isolates, and 13.7% for Klebsiella pneumoniae with 7 isolates, most of which were isolated from grade III fractures. The isolation rate of P. aeruginosa was 60% (6 isolates) from grade IIIA and 71.4% (5 isolates) from grade IIIB for K. pneumoniae, while for E. coli it was 69.2% (9 isolates) from grade IIIC. All the bacterial isolates recorded high levels of antibiotic resistance against most tested antibiotics. Wound cultures of grade II fractures appeared sterile after the first X-ray exposure, and these wounds were infected with S. aureus or P. aeruginosa. However, cultures of grade IIIA and IIIB fractures appeared sterile after the second X-ray exposure for all isolated bacteria, except for S. aureus (grade IIIA fractures) (after the third X-ray exposure). Grade IIIC fractures showed sterile culture after the third X-ray exposure for wounds infected with P. aeruginosa and E. coli. Conclusions The study concluded that X-ray exposure showed high effectiveness in treating infected open fractures.

Open Fractures: Are We Still Treating the Same Types of Infections?

Background: To analyze the rate of methicillin-resistant Staphylococcus aureus (MRSA), gram-negative, and polymicrobial infections in open fractures, measure the efficacy of the current open fracture antibiotic regimen against these infections, identify the most effective agent(s) to cover these infections, and analyze risk factors for infection. Methods: We examined retrospectively 451 patients with open fractures from January 2008 to December 2012 who were treated at our facility. Positive cultures during surgical debridement after wound closure defined an infection. Infecting organisms and their antibiotic sensitivities were identified through microbiology culture reports. Rates of MRSA, gram-negative, and polymicrobial infections were determined. The efficacy of the current regimen (cefazolin and gentamicin) was calculated against gram-positive and gram-negative organisms. Efficacy profiles against infectious organisms were calculated for all commonly tested antibiotics. Patient factors, injury characteristics, and treatment options were analyzed to determine risk factors for infection. Results: Ninety patients (20%) were identified as infected at surgical debridement. Of those 90, 21 (23.3%) were diagnosed with MRSA, 56 (62.2%) were found to have a gram-negative infection, and 46 (51.1%) had polymicrobial infections. Cephalosporins and β-lactam agents had a 59.2% efficacy rate against gram-positive bacteria and gentamicin showed a 94% sensitivity rate against gram-negative bacteria. Vancomycin (95.8% sensitivity) demonstrated the highest sensitivity for all gram-positive organisms. Amikacin (98.8% sensitivity), meropenem (96.3% sensitivity), and gentamicin (94.2% sensitivity) demonstrated excellent efficacy for all gram-negative organisms. Immuno-compromised status and Gustilo-Anderson type were the only independently predictive risk factors for infection in a multivariable model. Conclusions: Based on this analysis, the rate of MRSA, gram-negative, and polymicrobial infections in open fractures is high and increasing compared with historical cohorts. With the sensitivity of early generation cephalosporins being relatively poor against gram-positive organisms, the present antibiotic regimen for open, long-bone fractures may need to be reconsidered with these emerging trends.

Graphene-based nanomaterials combined with early exercise rehabilitation training in the treatment of patients with infectious bone defects

With the rapid development of industry and transportation, the incidence of open fractures caused by high-energy injuries has increased year by year, and bone infections are prone to occur after open fractures. According to the needs for the treatment of open fracture infections and bone defects, graphene in carbon nanomaterials has many advantages as bone graft materials. The purpose of this study was to make use of the unique physical and chemical properties of carbon nanomaterials to prepare a three-dimensional composite scaffold with good bone properties and some antibacterial properties, and carry antibiotics for the treatment of infection and bone defect after open fractures. The results show that the prepared reduced graphene oxide (RGO)-nHA composite scaffold has an interconnected three-dimensional porous structure, and the bone formation performance is enhanced when nHA is incorporated, which can promote cell growth and bone regeneration; vancomycin is loaded on this composite scaffold later, due to the bonding with graphene, the drug can be released relatively quickly in the initial stage, and then the drug is released slowly. The combination of the drug's sustained release characteristics and the inherent antibacterial activity of graphene can ensure rapid treatment of infections, and provide lasting inhibition of bacteria. In vivo experiments have also shown that the drug-loading system can effectively treat infectious bone defects.

Prevention of infection in open fractures: Where are the pendulums now?

Soft tissue management and fracture fixation including initial external fixation in Gustilo-Anderson type II and type III open fractures are cornerstones in the treatment but details on timing and type of wound closure, irrigation and debridement, systemic and local antibiotics, antimicrobial-coated implants and the use of Bone Morphogenetic Protein-2 remain controversial. This article looks at current clinical evidence of these items for the management of open fractures. Timing of debridement and wound closure remains critical. Early debridement by an experienced team within 24 h seems adequate while gross contamination, a devascularized limb, a multi-injured patient and compartment syndrome require immediate surgical intervention. Wound closure during the first surgery was shown to result in reduced rates for infections and nonunion. If soft-tissue reconstruction is needed, it should be performed within the first 7 days. Regarding types of irrigation fluid, antiseptic and antibacterial solutions did not prove to be superior to saline. High pressure irrigation has not been demonstrated to be beneficial whereas antibiotic administration as soon as possible has been proven to be favorable. Administration of more than 72 h was not superior to shorter systemic antibiotic intervals. For Gustilo-Anderson type I and II, broad spectrum antibiotic therapy is reasonable. Additional aminoglycosides for broader coverage are recommended in Gustilo-Anderson type III fractures. There is newer literature on the beneficial effects of the use of local antibiotics, e.g. by antibiotic beads. Coating of internal fixation devices is a modern approach to improve infection prophylaxis and gentamicin-coated implants have been demonstrated to be safe in clinical application. Vacuum assisted closure (VAC) could not evidence negative pressure wound therapy to reduce infection risk, improve self-rated disability or quality of life in open fractures, however, enhance treatment costs. Recombinant human bone morphogenetic proteins (rhBMP)-2 showed promising data in Gustilo-Anderson type III open tibial shaft fractures with lower rates of invasive secondary procedures. In conclusion, there is evidence for thorough debridement and irrigation with saline, early soft tissue coverage and the use of systemic and local antibiotics. Except for a short-term soft tissue coverage VAC seems not to be beneficial and rhBMP-2 is an additional tool in Gustilo-Anderson type III open fractures.

Treatment of Open Comminuted Diaphyseal Fracture of the Tibia by Ilizarov

Background: Management of open diaphyseal tibial shaft fractures can be comminuted due to lack of soft tissue coverage and blood supply of the tibial shaft. Open reduction and internal fixation [ORIF] with plates and screws achieves stability, allows joint mobilization but does not allow early weight bearing which as a stimulus is a must for early union. Closed reduction and intramedullary fixation compromise the intramedullary blood supply and increases the risk of infection in open fractures. Ilizarov is considered safe in treating these open injuries, at the same time it has the advantages of easy application, minimal invasive, and convenient subsequent soft tissue repair. Objective: The aim of current study was to evaluate treatment of open comminuted diaphyseal tibial fracture by ilizarov external fixator; its effective, availability, outcomes and complications. Patients and Methods: This prospective study included a total of 10 patients with comminuted tibial diaphyseal fractures managed with early Ilizarov external fixator, attending at Alharam Hospital. This study was conducted between Feb 2018 and July 2019. General assessment indicators included pain, complete union, deformity in comparison to healthy limb, infection, leg limb discrepancy, stiffness and activity of the patients were analysed. Results: Follow-up of all participants for analysis was done. The follow-up time was 17 months. Three cases developed ankle stiffness. The average total range of knee motion in our cases was 130.5 (range 125-140). A significant limp occurred only in 3 cases. NO persistent limp persisted in our cases. Fifteen patients had minimal pain at the site of fracture. Signicant pain occurred in three cases. Pin site infection occurred in 7 patients. All the patients achieved full union and activity. Excellent results were obtained in 4 cases (40%). Good results were obtained in 3 cases (30%) with overall good to excellent results were about (70%). Fair results were obtained in 3 cases (30%). Conclusion: It could be concluded that the Ilizarov external fixator is a golden horse for orthopedic surgeons. It holds wonderful promise in the management of open diaphyseal tibial shaft fractures.

Treatment of Open Comminuted Diaphyseal Fracture of the Tibia by Ilizarov

Background: Management of open diaphyseal tibial shaft fractures can be comminuted due to lack of soft tissue coverage and blood supply of the tibial shaft. Open reduction and internal fixation [ORIF] with plates and screws achieves stability, allows joint mobilization but does not allow early weight bearing which as a stimulus is a must for early union. Closed reduction and intramedullary fixation compromise the intramedullary blood supply and increases the risk of infection in open fractures. Ilizarov is considered safe in treating these open injuries, at the same time it has the advantages of easy application, minimal invasive, and convenient subsequent soft tissue repair. Objective: The aim of current study was to evaluate treatment of open comminuted diaphyseal tibial fracture by ilizarov external fixator; its effective, availability, outcomes and complications. Patients and Methods: This prospective study included a total of 10 patients with comminuted tibial diaphyseal fractures managed with early Ilizarov external fixator, attending at Alharam Hospital. This study was conducted between Feb 2018 and July 2019. General assessment indicators included pain, complete union, deformity in comparison to healthy limb, infection, leg limb discrepancy, stiffness and activity of the patients were analysed. Results: Follow-up of all participants for analysis was done. The follow-up time was 17 months. Three cases developed ankle stiffness. The average total range of knee motion in our cases was 130.5 (range 125-140). A significant limp occurred only in 3 cases. NO persistent limp persisted in our cases. Fifteen patients had minimal pain at the site of fracture. Signicant pain occurred in three cases. Pin site infection occurred in 7 patients. All the patients achieved full union and activity. Excellent results were obtained in 4 cases (40%). Good results were obtained in 3 cases (30%) with overall good to excellent results were about (70%). Fair results were obtained in 3 cases (30%). Conclusion: It could be concluded that the Ilizarov external fixator is a golden horse for orthopedic surgeons. It holds wonderful promise in the management of open diaphyseal tibial shaft fractures.

Prophylactic use of antibiotic laden poly methyl methacrylate beads in the management of open fractures: a novel approach for control of orthopaedic infection

<p class="abstract"><strong>Background:</strong> Control of infection in open fractures is a challenge in orthopaedic surgery. The literature provides evidence that antibiotic-laden bead chains are a useful adjuvant with systemic antibiotics in the prevention of infection in open fractures.</p><p class="abstract"><strong>Methods:</strong> Between February 2018 and January 2019, sixty four patients with open type fractures admitted in emergency room were analysed for this study. In this 64 patients, 32 in Group A received antibiotic laden PMMA (Poly methyl methacrylate) beads with standard care. Another 32 in Group B received standard care.<strong></strong></p><p class="abstract"><strong>Results:</strong> There were 54 males and 10 females with a mean age of 41 and follow up 6 months. Among 64 patients 37 patients were stabilised with external fixators and remaining 17 patients underwent a definitive fixation either an intramedullary nailing (12 patients) or internal fixation with a plate (5 patients). 10 patients were stabilised with k wires. The infection rate in group A and B was 6.25% and 21.8% respectively which is statistically not significant (p=0.072).</p><p class="abstract"><strong>Conclusions:</strong> Although the final infection control rate was comparable between the bead group (30/32, 93.75%) and the non bead group (25/32, 78.12%), few complications were noted in the bead group (9.37%, 3/32) than in the group B (15.62%, 5/32). Hence the prophylactic use of antibiotic cement beads is advantageous in preventing post traumatic orthopaedic infection, lessens hospital stay as well the financial burden to the patients.</p>

Early Outcome of Culture-Negative Infection in Open Fractures of the Lower Limb: A Prospective Study

AbstractBackground: Culture-negative infections in open long bone fractures are frequently encountered in clinical practice. We aimed to identify the rate and outcome of culture-negative infections in open long bone fractures of lower limb. Methodology: A prospective cohort study was conducted from November 2015 to May 2017 on Gustilo and Anderson Grade III open long bone fractures of the lower limb. Demographic data, injury details, time from injury to receiving antibiotics and index surgical procedure were noted. Length of hospital stay, number of additional surgeries and occurrence of complications were also noted. Patients with infected open fractures were grouped as culture positive or culture negative depending on the isolation of infecting microorganisms in deep intraoperative specimen. The clinical outcome of these two groups was statistically analysed. Results: A total of 231 patients with 275 open fractures involving the femur, tibia or fibula were studied. There was clinical signs of infection in 84 patients (36.4%) with 99 fractures (36%). Forty-three patients (51.2%) had positive cultures and remaining 41 patients had negative cultures (48.8%). The rate of culture-negative infection in open type III long bone fractures in our study was 17.7%. There was no statistical difference in the clinical outcome between culture-negative and culture-positive infections. Conclusion: Failure to identify an infective microorganism in the presence of clinical signs of infection is routinely seen in open fractures and needs to be treated aggressively.

Efficacy of Antibiotic Laden Collagen Sponge In Treating Open Fracture

Introduction: Open fractures are known as a major predisposing factor for a higher incidence of infection. The aim of this study was to assess the efficacy of antibiotic impregnated collagen sponge in reducing the risk of infection in open fractures Grade 3. Materials and Methods: This was an observational cohort study, evaluating the incidence of infection in open fractures of the femur Grade 3A/3B following insertion of gentamicin impregnated collagen sponge (Collatamp®) during definitive fracture fixation. Eryhtrocyte Sedimentation Rate (ESR) and total white count (TWC) were used as blood parameters to observe for the possibility of infection from pre-operatively up to follow up visits at the clinic. Results: A total number of 36 patients, whom had sustained open fracture of the femur Grade 3A/B, underwent internal fixation with antibiotic impregnated collagen sponge insertion. Overall, ESR and TWC in both male and female gender were downgoing trend, with p values of <0.001, and clinically there was no evidence of infection. No infection was identified in 97.2% of patients, following the internal fixation and antibiotic impregnated collagen sponge insertion. There was only one patient (2.8%) who developed infection following the definitive internal fixation and antibiotics impregnated collagen sponge insertion. Conclusion: The use of antibiotic impregnated collagen sponge in open fractures reduced the occurrence of infection. Furthermore, this allows for an uncomplicated union of the bone following definitive fixation.

Microbiological Study of Etiological Pathogen in Early Infection of Open Fracture in Orthopedics

Introduction: Infection is a dreaded complication of open fracture in the field of orthopaedics. This study was conducted to evaluate the susceptibility of microorganism involved in early infection of open fractures to current prophylactic antibiotics practice and determine the association of various characteristics to the resistance of such microorganisms. Materials and Methods: This cross sectional study was conducted from January 2015 to December 2017 in Hospital Tengku Ampuan Afzan, Kuantan, Malaysia. A total of 179 cases were collected from the operating record with 110 cases fulfilling the inclusion and exclusion criteria. The patients underwent routine debridement where culture and sensitivity were followed up. Previous notes were traced to identify the various risk factors involved and evaluated against resistance of microorganism. Statistical analysis was done with SPSS version 23 applying Pearson chi-square tests and Fisher's exact test. Results: Admission to intensive care unit, blood transfusion, antibiotic regime and duration, fracture grade, injury severity score and duration of admission were all significantly associated with resistance of microorganism (p < 0.0001). This study also demonstrated 65.9% predominance of Gram-negative microorganisms. These gram-negative microorganisms were seen more in higher fracture grades, injury severity score, and longer duration of admission or antibiotics prescribed. The overall resistance to cefuroxime and gentamicin were 68.6% and 36.9% respectively. Conclusion: The shift of microorganism species to gram-negative and the high rate of resistance suggested that current antibiotic guidelines and regime needed to be fine-tuned to achieve optimal results in managing open fracture.

A prospective study on results of bacterial culture from wound in type III compound fractures

<p class="abstract"><strong>Background:</strong> Open fractures still represent a major challenge for the treating surgeon. Sound knowledge of the bacteriological epidemiology and antimicrobial susceptibility helps to prevent complications. Our aim is to study about the common bacteria causing open fracture infection and their antibiotic sensitivity in patients who are admitted in the department of Orthopedics, Government medical college, Kottayam.</p><p class="abstract"><strong>Methods:</strong> A prospective study on 130 patients with type III open long bone fractures were studied for infection during study period of June 2016 to July 2017. After initial debridement and at third day during follow up wound inspection, swabs were taken from wound site. Swabs were send for microscopic examination, culture and antimicrobial susceptibility testing.<strong></strong></p><p class="abstract"><strong>Results:</strong> Out of 130 type III open long bone fractures, 7.7% were having day 0 infection and 25.4% were having day 3 infection. 19.2% of patients developed infection from day 3 onwards. <em>Staphylococcus aureus</em> (37.1%) was the most commonly isolated bacteria from wound. Other organisms isolated were <em>Acinetobacter, Pseudomonas, Klebsiella</em>, <em>E coli</em>, <em>Enterococcus</em>, <em>Streptococcus</em> and <em>Enterobacter</em>. 100% of diabetic patients developed infection on day 3. Gentamicin, amikacin doxycycline, ciprofloxacin, vancomycin, piperacillin + tazobactum and cefoperazone + sulbactum were found to be effective against isolated organisms.</p><p class="abstract"><strong>Conclusions:</strong> Gram positive <em>Staphylococcus aureus</em> was found to be the most common cause of wound infection in type III open fractures. An early adequate wound debridement, proper antibiotic therapy and aseptic post-operative wound care are essential for wound healing and fracture union in an open fracture.</p>

CSA-90 Promotes Bone Formation and Mitigates Methicillin-resistant Staphylococcus aureus Infection in a Rat Open Fracture Model.

Infection of open fractures remains a significant cause of morbidity and mortality to patients worldwide. Early administration of prophylactic antibiotics is known to improve outcomes; however, increasing concern regarding antimicrobial resistance makes finding new compounds for use in such cases a pressing area for further research. CSA-90, a synthetic peptidomimetic compound, has previously demonstrated promising antimicrobial action against Staphylococcus aureus in rat open fractures. However, its efficacy against antibiotic-resistant microorganisms, its potential as a therapeutic agent in addition to its prophylactic effects, and its proosteogenic properties all require further investigation. (1) Does prophylactic treatment with CSA-90 reduce infection rates in a rat open fracture model inoculated with S aureus, methicillin-resistant S aureus (MRSA), and methicillin-resistant Staphylococcus epidermidis (MRSE) as measured by survival, radiographic union, and deep tissue swab cultures? (2) Does CSA-90 reduce infection rates when administered later in the management of an open fracture as measured by survival, radiographic union, and deep tissue swab cultures? (3) Does CSA-90 demonstrate a synergistic proosteogenic effect with bone morphogenetic protein 2 (BMP-2) in a noninfected rat ectopic bone formation assay as assessed by micro-CT bone volume measurement? (4) Can CSA-90 elute and retain its antimicrobial efficacy in vitro when delivered using clinically relevant agents measured using a Kirby-Bauer disc diffusion assay? All in vivo studies were approved by the local animal ethics committee. In the open fracture studies, 12-week-old male Wistar rats underwent open midshaft femoral fractures stabilized with a 1.1-mm Kirschner wire and 10 µg BMP-2 ± 500 µg CSA-90 was applied to the fracture site using a collagen sponge along with 1 x 10 colony-forming units of bacteria (S aureus/MRSA/MRSE; n = 10 per group). In the delayed treatment study, débridement and treatment with 500 µg CSA-90 were performed at Day 1 and Day 5 after injury and bacterial insult (S aureus). All animals were reviewed daily for signs of local infection and/or sepsis. An independent, blinded veterinarian reviewed twice-weekly radiographs, and rats showing osteolysis and/or declining overall health were culled at his instruction. The primary outcome of both fracture studies was fracture infection, incorporating survival, radiographic union, and deep tissue swab cultures. For the ectopic bone formation assay, 0 to 10 µg BMP-2 and 0 to 500 µg CSA-90 were delivered on a collagen sponge into bilateral quadriceps muscle pouches of 8-week-old rats (n = 10 per group). Micro-CT quantification of bone volume and descriptive histologic analysis were performed for all in vivo studies. Modified Kirby-Bauer disc diffusion assays were used to quantify antimicrobial activity in vitro using four different delivery methods, including bone cement. Infection was observed in none of the MRSA inoculated open fractures treated with CSA-90 with 10 of 10 deep tissue swab cultures negative at the time of cull. Median survival was 43 days (range, 11-43 days) in the treated group versus 11 days (range, 8-11 days) in the untreated MRSA inoculated group (p < 0.001). However, delayed débridement and treatment of open fractures with CSA-90 at either Day 1 or Day 5 did not prevent infection, resulting in early culls by Day 21 with positive swab cultures (10 of 10 for each time point). Maximal ectopic bone formation was achieved with 500 μg CSA-90 and 10 μg BMP-2 (mean volume, 9.58 mm; SD, 7.83), creating larger bone nodules than formed with 250 μg CSA-90 and 10 μg BMP-2 (mean volume, 1.7 mm; SD, 1.07; p < 0.001). Disc diffusion assays showed that CSA-90 could successfully elute from four potential delivery agents including calcium sulphate (mean zone of inhibition, 11.35 mm; SD, 0.957) and bone cement (mean, 4.67 mm; SD, 0.516). CSA-90 shows antimicrobial action against antibiotic-resistant Staphylococcal strains in vitro and in an in vivo model of open fracture infection. The antimicrobial properties of CSA-90 combined with further evidence of its proosteogenic potential make it a promising compound to develop further for orthopaedic applications.

Comparative accuracy assessment of the Gustilo and Tscherne classification systems as predictors of infection in open fractures

ObjectiveThe aim of this study is to analyze the accuracy of the two classification systems for open fractures most commonly used in current medical practice, Gustilo and Tscherne, as predictors of infection. MethodsA retrospective observational study was performed, including 121 patients suffering from open fracture of the appendicular skeleton treated at an emergency hospital. The fractures were classified according to Gustilo and Tscherne systems during the initial treatment, and ratings were subsequently confirmed or rectified during hospitalization. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated according to each classification adopted. ResultsThe results of this study demonstrated that both classifications of Gustilo and Tscherne are associated with the clinical outcome of infection in open fractures. The Gustilo classification achieved sensitivity of 76.7%, specificity of 53.8%, and accuracy of 59.5%. Tscherne's classification had a sensitivity of 56.7%, specificity 82.4%, and accuracy of 76.1%. ConclusionThe Tscherne system showed better accuracy, including specificity as a predictor of infection in open fractures, when compared with the Gustilo system.

Assessment of a Modified Antibiotic Prophylaxis Open Fracture Protocol

Background National guidelines support antibiotic prophylaxis for open fracture with cefazolin +/− aminoglycoside based on fracture grade and contamination. The purpose of this study was to assess a modified adult antibiotic prophylaxis open fracture protocol (AOFP) which recommended weight-based cefazolin for low-grade fractures or ciprofloxacin plus vancomycin for high-grade fractures.Methods Adult patients with open fractures admitted to Palmetto Health Richland between January 2012 and December 2016 were screened for study inclusion. Exclusion criteria were receipt of antibiotics for reasons other than open fracture, death prior to wound closure, and local admission time >48 hours after time of injury. Compliance to all elements of AOFP was assessed. Clinical endpoints including open fracture infection rates, epidemiology, and drug-related adverse events were compared between pre-implementation (January 2012 – December 2012) and post-implementation period (November 2015 – December 2016). χ 2 and t-tests as appropriate were used to compare outcomes between groups.ResultsFollowing exclusions 189 patients were included in the analysis (90 pre- vs. 99 post-AOFP, respectively). Post-AOFP, a 17% (16/93) adherence rate to all AOFP elements was found. Appropriate agents were selected in 82.8% (77/93). The most common reasons for non-adherence were incorrect dosing and prolonged antibiotic duration. Fracture site infection rates were 23.3% (21/90) and 7.1% (7/99) in pre- and post-AOFP groups, respectively (P = 0.001). Infections primary caused by Gram-negative pathogens in pre-AOFP and Gram-negative organisms comprised 62 and 40% of open fracture site infections in pre- and post-AOFP groups, respectively. Incidence of acute kidney injury, Clostridium difficile-associated diarrhea, and other antibiotic-associated AEs were rare and comparable between groups. Change in median days to infection (55.6 days vs. 56.55 days, P = 0.71) and median duration of antibiotics in hours (48.0 vs. 54.7, P = 0.59) was not significantly different post implementation.Conclusion Local adherence to all elements of the modified AOFP was low, yet the appropriate agent(s) was used in majority of cases. The modified AOFP was associated with a numerical decrease in infection rates post-open fracture and comparable AEs.Disclosures P. B. Bookstaver, Rock Pointe: Content Developer, Consulting fee

Trauma surgery in Pacific Small Island Developing States (SIDS)

The small developing countries in the Pacific are grouped together as Small Island Development States (SIDS) because they face similar problems which they cannot cope with nationally. They are developing countries, so-called low and lower middle income countries (LMIC), are economically weak and the islands of the different nations are widely scattered. Approximately 80% of the 10 million inhabitants live in rural regions. Over 40% of patients in the surgical departments of hospitals are hospitalized for injuries, and this tendency is increasing. Fractures of the upper extremities are relatively more frequent in the Pacific than in the countries of the North. Long distances, lack of possibilities for treatment and lack of transport often cause complications, such as infected open fractures, pseudarthrosis and posttraumatic malformations. There are too few hospitals with sufficiently competent surgeons, anesthetists and obstetricians (SAO) and appropriate equipment. The PIOA was founded in Honiara, Solomon Islands, and offers surgeons of the Pacific SIDS acomprehensive, structured trauma and orthopedic surgery training in their own countries. It lasts 4 years and leads to an M‑Med (orthopaedic surgery) diploma and to aFellowship of the International College of Surgeons (FICS), which are both recognized by the participating hospitals. It is free for participants. The AOAF is an independent organization with the only aim to enhance trauma surgery capacity in LMICs. The AOAF supports the PIOA program together with the Wyss Medical Foundation. Currently, 18trainees from 8 Pacific SIDS are participating in the PIOA training program.

Análise comparativa da acurácia das classificações de Gustilo e Tscherne como preditoras de infecção em fraturas expostas

ObjectiveThe aim of this study is to analyze the accuracy of the two classification systems for open fractures most commonly used in current medical practice, Gustilo and Tscherne, as predictors of infection. MethodsA retrospective observational study was performed, including 121 patients suffering from open fracture of the appendicular skeleton treated at an emergency hospital. The fractures were classified according to Gustilo and Tscherne systems during the initial treatment, and ratings were subsequently confirmed or rectified during hospitalization. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated according to each classification adopted. ResultsThe results of this study demonstrated that both classifications of Gustilo and Tscherne are associated with the clinical outcome of infection in open fractures. The Gustilo classification achieved sensitivity of 76.7%, specificity of 53.8%, and accuracy of 59.5%. Tscherne's classification had a sensitivity of 56.7%, specificity 82.4%, and accuracy of 76.1%. ConclusionThe Tscherne system showed better accuracy, including specificity as a predictor of infection in open fractures, when compared with the Gustilo system.