Evaluating the use of antibiotic prophylaxis during open reduction and internal fixation surgery in patients at low risk of surgical site infection

Dose regimen optimization of cephalothin for surgical prophylaxis against Staphylococcus aureus and coagulase negative staphylococci in dogs by pharmacokinetic/pharmacodynamic modeling

First generation cephalosporins such cephalothin of cefazolin are indicated for antimicrobial prophylaxis for clean and clean contaminated surgical procedures because its antimicrobial spectrum, relative low toxicity and cost. Anesthesia and surgery could alter the pharmacokinetic behavior of different drugs administered perioperative by many mechanisms that affect distribution, metabolism or excretion processes. Intravenous administration of the antimicrobial within 30 and 60 min before incision is recommended in order to reach therapeutic serum and tissue concentrations and redosing is recommended if the duration of the procedure exceeds two half-life of the antimicrobial. To the author's knowledge there are no pharmacokinetic studies of cephalothin in dogs under anesthesia/surgery conditions. The aim of this study was (1) to evaluate the pharmacokinetics of cephalothin in anesthetized dogs undergoing ovariohysterectomy by a nonlinear mixed-effects model and to determine the effect of anesthesia/surgery and other individual covariates on its pharmacokinetic behavior; (2) to determine the MIC and conduct a pharmacodynamic modeling of time kill curves assay of cephalothin against isolates of Staphylococcus spp. isolated from the skin of dogs; (3) to conduct a PK/PD analysis by integration of the obtained nonlinear mixed-effects models in order to evaluate the antimicrobial effect of changing concentrations on simulated bacterial count; and (4) to determine the PK/PD endpoints and PK/PDco values in order to predict the optimal dose regimen of cephalothin for antimicrobial prophylaxis in dogs. Anesthesia/surgery significantly reduced cephalothin clearance by 18.78%. Based on the results of this study, a cephalothin dose regimen of 25 mg/kg q6h by intravenous administration showed to be effective against Staphylococcus spp. isolates with MIC values ≤2 μg/mL and could be recommended for antimicrobial prophylaxis for clean surgery in healthy dogs.

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.

Surgical Antimicrobial Prophylaxis in Patients of Neonatal and Pediatric Age Undergoing Orthopedic and Hand Surgery: A RAND/UCLA Appropriateness Method Consensus Study

Surgical site infections (SSIs) represent a potential complication in any type of surgery and can occur up to one year after the procedure in the case of implant placement. In the field of orthopedic and hand surgery, the rate of SSIs is a relevant issue, considering the need for the placement of synthesis devices and the type of some interventions (e.g., exposed fractures). This work aims to provide guidance on the management of peri-operative antibiotic prophylaxis for the pediatric and neonatal population undergoing orthopedic and hand surgery in order to standardize the management of patients and to reduce, on the one hand, the risk of SSI and, on the other, the development of antimicrobial resistance. The following scenarios were considered: (1) bloodless fracture reduction; (2) reduction of unexposed fracture and grade I and II exposed fracture; (3) reduction of grade III exposed fracture or traumatic amputation; (4) cruel fracture reduction with percutaneous synthesis; (5) non-traumatic amputation; (6) emergency intact skin trauma surgery and elective surgery without synthetic media placement; (7) elective orthopedic surgery with prosthetic and/or synthetic media placement and spinal surgery; (8) clean elective hand surgery with and without bone involvement, without use of synthetic means; (9) surgery of the hand on an elective basis with bone involvement and/or with use of synthetic means. This manuscript has been made possible by the multidisciplinary contribution of experts belonging to the most important Italian scientific societies and represents, in our opinion, the most complete and up-to-date collection of recommendations regarding the behavior to be adopted in the peri-operative setting in neonatal and pediatric orthopedic and hand surgery. The specific scenarios developed are aimed at guiding the healthcare professional in practice to ensure the better and standardized management of neonatal and pediatric patients, together with an easy consultation.

Management of surgical site infection post-open reduction and internal fixation for tibial plateau fractures

AIMS

In contrast to operations performed for other fractures, there is a high incidence rate of surgical site infection (SSI) post-open reduction and internal fixation (ORIF) done for tibial plateau fractures (TPFs). This study investigates the effect of induced membrane technique combined with internal fixation for managing SSI in TPF patients who underwent ORIF.

METHODS

From April 2013 to May 2017, 46 consecutive patients with SSI post-ORIF for TPFs were managed in our centre with an induced membrane technique. Of these, 35 patients were included for this study, with data analyzed in a retrospective manner.

RESULTS

All participants were monitored for a mean of 36 months (24 to 62). None were subjected to amputations. A total of 21 patients underwent two-stage surgeries (Group A), with 14 patients who did not receive second-stage surgery (Group B). Group A did not experience infection recurrence, and no implant or cement spacer loosening was noted in Group B for at least 24 months of follow-up. No significant difference was noted in the Lower Extremity Functional Scale (LEFS) and the Hospital for Special Surgery Knee Score (HSS) between the two groups. The clinical healing time was significantly shorter in Group B (p＜0.001). Those with longer duration of infection had poorer functional status (p＜0.001).

CONCLUSION

Management of SSI post-ORIF for TPF with induced membrane technique combined with internal fixation represents a feasible mode of treatment with satisfactory outcomes in terms of infection control and functional recovery. Cite this article: Bone Joint Res 2021;10(7):380-387.

Prospective Analysis of Hand Infection Rates in Elective Soft Tissue Procedures of the Hand: The Role of Preoperative Antibiotics

Background: The purpose of this study was to evaluate the efficacy of prophylactic antimicrobial prophylaxis in elective hand surgery in preventing postoperative infection. Methods: Between 2009 and 2012, we performed a multicenter trial in which patients undergoing elective hand surgeries were categorized into an antibiotic or control group depending on the center they were enrolled in. Surgical site infections were defined according to the Centers for Diseases Control and Prevention. Results: In total, 434 patients were included: 257 did not receive antibiotics (control) and 177 received antibiotics at a mean age of 61.0 years. In the control group, comorbidities were more common with 23.7% (61/257) in comparison to the antibiotics group with 14.1% (25/177). Only one surgical site infection in each group was identified. One wound was opened surgically, and an antimicrobial treatment was indicated in both cases. In addition, we observed four complications in the control group and three complications in the antibiotics group which required conservative management. No significant differences in the two cohorts in infection rate (0.006% vs 0.003%, χ² = 0.07, P > .05) and complication rate (2.8% vs 1.6%, χ² = 0.01, P > .05) were found. Conclusions: Our prospective multicenter trial showed no significant difference in infection rate in elective hand surgery whether antibiotics were administered preoperatively or not.

Surgical Infection Society Research Priorities: A Narrative Review of Fourteen Years of Progress

Background: In 2006, the Surgical Infection Society (SIS) utilized a modified Delphi approach to define 15 specific priority research questions that remained unanswered in the field of surgical infections. The aim of the current study was to evaluate the scientific progress achieved during the ensuing period in answering each of the 15 research questions and to determine if additional research in these fields is warranted. Methods: For each of the questions, a literature search using the National Center for Biotechnology Information (NCBI) was performed by the Scientific Studies Committee of the SIS to identify studies that attempted to address each of the defined questions. This literature was analyzed and summarized. The data on each question were evaluated by a surgical infections expert to determine if the question was answered definitively or remains unanswered. Results: All 15 priority research questions were studied in the last 14 years; six questions (40%) were definitively answered and 9 questions (60%) remain unanswered in whole or in part, mainly because of the low quality of the studies available on this topic. Several of the 9 unanswered questions were deemed to remain research priorities in 2020 and warrant further investigation. These included, for example, the role of empiric antimicrobial agents in nosocomial infections, the use of inotropes/vasopressors versus volume loading to raise the mean arterial pressure, and the role of increased antimicrobial dosing and frequency in the obese patient. Conclusions: Several surgical infection-related research questions prioritized in 2006 remain unanswered. Further high-quality research is required to provide a definitive answer to many of these priority knowledge gaps. An updated research agenda by the SIS is warranted at this time to define research priorities for the future.

Modifications of Hydroxyapatite by Gallium and Silver Ions-Physicochemical Characterization, Cytotoxicity and Antibacterial Evaluation

Hydroxyapatite (HA) powders enriched with silver or gallium ions or both were synthesized by two different routes: standard precipitation and the solid-state method. The powders were characterized by using several methods: inductively coupled plasma optical emission spectrometry (ICP-OES), powder X-ray diffractometry (PXRD), transmission electron microscopy (TEM), infrared spectroscopy (FT-IR) and solid-state nuclear magnetic resonance spectroscopy (ssNMR). The effects of enrichment of the HAs in Ag⁺ or Ga³⁺ or both on in vitro cytotoxicity and microbiological activity were discussed. PXRD experiments showed that the samples obtained by the wet method consisted of single-phase nanocrystalline HA, while the samples prepared via the solid-state method are microcrystalline with a small amount of calcium oxide. The introduction of higher amounts of silver ions was found to be more effective than enriching HA with small amounts of Ag⁺. Gallium and silver ions were found not to affect the lattice parameters. Ga³⁺ affected the crystallinity of the samples as well as the content of structural hydroxyl groups. Among samples synthesized by the wet method, only one (5Ag-HAw) was cytotoxic, whereas all Ga-containing samples obtained by the dry method showed cytotoxicity. In the preliminary antimicrobial test all the materials containing "foreign" ions showed high antibacterial activity.

Population Pharmacokinetic Study of Cefazolin Used Prophylactically in Canine Surgery for Susceptibility Testing Breakpoint Determination

This study aimed to determine the population pharmacokinetic (Pop PK) parameters of cefazolin administered prophylactically at 25 mg/kg intravenously (IV) 30 min before surgery in a canine population of 78 dogs and assess whether covariates, such as sex, age, body weight (BW), breed, health status, creatinine level, and surgery time, have an influence on cefazolin disposition. The ultimate goal was to compute PK/PD cut off values and subsequently establish a specific clinical breakpoint (CBP) for the development of an antimicrobial susceptibility test (AST) of cefazolin in dogs according to the VetCAST approach. Two to 11 blood samples were collected from each dog from 5 to 480 min after cefazolin administration. A two-compartment model was selected, and parameterization was in terms of serum clearance (CL), intercompartmental CL(s) (Q) and volume(s) of distribution (V). The percentage of cefazolin binding to serum protein was 36.2 ± 5.3%. Population primary parameter estimates V1, V2, CL, and Q were (typical value ± SE) 0.116 ± 0.013 L/kg, 0.177 ± 0.011 L/kg, 0.0037 ± 0.0002 L/kg/min, and 0.0103 ± 0.0013 L/kg/min, respectively. Cefazolin presented rapid distribution and elimination half-lives (mean ± SE) 4.17 ± 0.77 min and 57.93 ± 3.11 min, respectively. The overall between-subject variability (BSV) for estimated primary parameters ranged from 36 to 42%, and none of the seven explored covariates were able to reduce this variability by an amplitude clinically relevant. By Monte Carlo simulation, the probability of a PK/PD target attainment (here to achieve a free serum concentration exceeding the MIC for 50% of the dosing interval in 90% of dogs) was computed with a dosage of 25 mg/kg administered IV every 6 h for 4 administrations in 24 h. The computed PK/PD cut off value was 2 mg/L. In conclusion, cefazolin administered prophylactically in surgical dogs at 25 mg/kg IV every 6 h was deemed effective against pathogens with a MIC value ≤ 2 mg/L and from a PK/PD perspective, can be recommended in a wide range of canine patient populations with no necessary dose adjustment for special dog subpopulations.

[Prevention of postoperative infections : Risk factors and the current WHO guidelines in musculoskeletal surgery]

BACKGROUND

Despite the many scientific and technological advances postoperative infection continues to be a large problem for trauma and orthopedic surgeons. Based on a review of the current literature, this study provides a comprehensive overview of the risk factors (RF) and possible preventive measures to control surgical site infections.

METHODS

Medline search and analysis from 1968-2017 (as of 01 March 2017). Selection of trauma and orthopedic relevant RFs and comparison with WHO recommendations (global guidelines for the prevention of surgical site infection, Nov. 2016).

RESULTS

Identification of 858 relevant articles from the last 50 years (1968-2017). Pooled postoperative rate of infection is 0.3% (hand surgery) and 19% (3rd degree open fractures). For open fractures, there is no clear tendency towards lower infection rates during the past five decades. Identification of 115 RF from three areas (patient-dependent RF, organizational and procedural RF, trauma- and surgery-dependent RF). The five most important RFs are body mass index over 35 kg/m², increased duration of surgery, diabetes mellitus, increased blood glucose levels in the perioperative period also in the case of nondiabetic patients, and errors in the perioperative antibiotic prophylaxis.

DISCUSSION

Inconsistent definition of "infection", interaction of the RF and the different follow-up duration limit the meaningfulness of the study.

CONCLUSION

In the future, considerable efforts must be made in order to achieve a noticeable reduction in the rate of infection, especially in the case of high-risk patients.

Infection following fractures of the proximal tibia - a systematic review of incidence and outcome

Background

To systematically review all available studies of operatively treated proximal tibia fractures and to report the incidence of superficial or deep infection and subsequent outcomes.

Methods

A systematic review of the literature in Medline, Cochrane, Embase and GoogleScholar was conducted to identify studies with cohorts of patients with infection after surgical treatment of proximal tibia fractures. Studies were included according to predefined inclusion and exclusion criteria. The studies were analysed for methodological deficiencies and quality of outcome reporting based on the Level of Evidence (LOE) and Coleman Methodology Scoring (CMS.)

Results

In total 32 studies were included. There was heterogeneity between the studies, in terms of subject of the studies, outcome criteria, fracture type and classification, surgical techniques and length of follow-up. Therefore, no meta-analysis could be performed. The average CMS was 54.2 (range 36–75). The included studies were 25 case series (LOE IV), 6 were prospective cohort studies (LOE III) and one was a prospective randomized trial (LOE I). 203 (12.3%, range: 2.6–45.0%) infections occurred in the overall population (n = 2063). Those were divided into 129 deep infections and 74 superficial infections. Revision due to infection was reported in 29 studies, microbiological results in 6, respectively. 72 (55,8%) of 129 cases reporting outcome after deep infection had an unsatisfactory outcome with substantial limitations of the affected joint and leg.

Conclusions

Postoperative infections are a challenge, sometimes requiring several revisions and often with a worse outcome. Further studies with structured study protocols should be performed for a better understanding of risk factors to improve treatment outcomes.

Economic case for intraoperative interventions to prevent surgical-site infection

BACKGROUND

Surgical-site infection (SSI) occurs in 1-10 per cent of all patients undergoing surgery; rates can be higher depending on the type of surgery. The aim of this review was to establish whether (or not) surgical hand asepsis, intraoperative skin antisepsis and selected surgical dressings are cost-effective in SSI prevention, and to examine the quality of reporting.

METHODS

The authors searched MEDLINE via Ovid, CINAHL via EBSCO, Cochrane Central and Scopus databases systematically from 1990 to 2016. Included were RCTs and quasi-experimental studies published in English, evaluating the economic impact of interventions to prevent SSI relative to surgical hand and skin antisepsis, and wound dressings. Characteristics and results of included studies were extracted using a standard data collection tool. Study and reporting quality were assessed using SIGN and CHEERS checklists.

RESULTS

Across the three areas of SSI prevention, the combined searches identified 1214 articles. Of these, five health economic studies evaluating the cost-effectiveness of selected surgical dressings were eligible. Study authors concluded that the interventions being assessed were cost-effective, or were potentially cost-saving. Still, there is high uncertainty around the decision to adopt these dressings/devices in practice. The studies' reporting quality was reasonable; three reported at least 15 of the 24 CHEERS items appropriately. Assessment of methodological quality found that two studies were considered to be of high quality.

CONCLUSION

With few economic studies undertaken in this area, the cost-effectiveness of these strategies is unclear. Incorporating economic evaluations alongside RCTs will help towards evidence-informed decisions.

Bacterial inhibition potential of quaternised chitosan-coated VICRYL absorbable suture: An in vitro and in vivo study

BACKGROUND/OBJECTIVE

As a widely used absorbable suture with antibacterial property, triclosan- coated polyglactin suture (Vicryl Plus) has been extensively utilized to reduce the occurrence rate of surgical site infections (SSIs) in orthopaedic surgery. However, the potential toxicity and side-effects of triclosan raised increasing concerns about its biological safety. This study aimed to investigate the antimicrobial activity and biocompatibility of quaternised chitosan-coated Vicryl suture (HV) both in vitro and in vivo.

METHODS

In this study, a modified chitosan derivate, (hydroxypropyltrimethyl ammonium chloride chitosan, HACC), was coated over the surface of the absorbable Vicryl suture. Two standard bacteria strains, Staphylococcus epidermidis (ATCC35984) and methicillin-resistant Staphylococcus aureus (ATCC43300), were selected to evaluate bacterial adhesion and biofilm formation on the sutures at 6, 24 and 48 h in vitro. Additionally, human skin-derived fibroblasts cells were used to test the cytocompatibility of the sutures. Furtherly, sutures contaminated with methicillin-resistant S. aureus were implanted subcutaneously in SD rats in order to confirm the in vivo antibacterial performance and biocompatibility.

RESULTS

We found that HACC-coated Vicryl suture (HV) exhibited significant anti-bacterial effects on the two tested strains. The bacterial attachment and biofilm formation on the surface of the HV sutures were found to be comparable to that of Vicryl Plus sutures (VP). Moreover, all the four tested sutures presented good cytocompatibility with human skin-derived fibroblasts cells. Histology and immunohistochemistry results indicated that the infections and inflammations were significantly inhibited around the HV and VP sutures.

CONCLUSION

In general, the present study demonstrated that the quaternised chitosan coating is a flexible and cost-effective alternative strategy to prevent the suture related surgical site infections in orthopaedic practices.

Survey of Intraoperative Bacterial Contamination in Dogs Undergoing Elective Orthopedic Surgery

OBJECTIVE

To investigate the frequency, source, and risk factors of intraoperative (IO) surgeon and patient bacterial contamination during clean orthopedic surgeries, and to investigate the relationship between IO contamination and surgical site infection (SSI) in dogs.

STUDY DESIGN

Prospective clinical study.

SAMPLE POPULATION

Client-owned dogs undergoing stifle surgery (n = 100).

METHODS

IO cultures were taken in each case from surgical foot wrap, peri-incisional skin, surgical gloves, and the surgical team's hands. The environment (operating room [OR] lights, computers, scrub sink faucet, anesthesia gurney, and radiology table) was sampled every 5 months. Bacteria were identified and the contamination of each case was categorized. All gloves from the surgical team were collected and tested for perforations using a water infusion test. Cases were followed for at least 8 weeks to determine the presence or absence of SSI. Perioperative variables were evaluated for association with IO contamination and SSI.

RESULTS

Bacterial isolates were yielded from 81% of procedures from 1 or more sources; 58% had positive hand cultures, 46% had positive glove cultures, 23% had positive patient skin cultures, and 12% had positive foot wrap cultures. Staphylococcus spp. was the most commonly recovered bacteria. There was no apparent association between IO contamination and SSI. The highest level of environmental contamination was associated with the scrub sink faucet, followed by the radiology table, anesthesia gurney, and OR computers. The IO glove perforation rate was 18%.

CONCLUSION

Clean orthopedic procedures commonly had clinically insignificant bacterial contamination. In our study, bacteria responsible for SSI did not appear to colonize the patient in the OR.