Does Topical Vancomycin Powder Use in Fracture Surgery Change Bacteriology and Antibiotic Susceptibilities? An Analysis of the VANCO Trial

OBJECTIVE

To determine whether intrawound vancomycin changes the bacteriology of surgical site infection pathogens and investigate the emergence of antibiotic-resistant pathogens.

METHODS

DESIGN

Secondary analysis of phase III, prospective, randomized clinical trial.

SETTING

Thirty-six US trauma centers.

PATIENT SELECTION CRITERIA

Patients who became infected after fixation of tibial plateau or pilon fracture.

OUTCOME MEASURES AND COMPARISONS

Pathogen types and bacterial susceptibilities as determined from routine clinical culture in the operating room.

RESULTS

Seventy-four patients were studied who were 67.5% male with a mean age of 48.6 years. A lower proportion of gram-positive cocci was observed in the vancomycin powder compared with the standard-of-care group (3.7% vs. 8.0%, P = 0.01). Methicillin-resistant Staphylococcus aureus infection incidence was comparable in both the vancomycin powder and the standard-of-care groups, but rates of methicillin-susceptible S. aureus infections were lower in the treatment group (1.4% vs. 4.8%, P = 0.01). The incidence of coagulase-negative Staphylococci and gram-negative rod infections were similar in both groups. There was no significant difference in susceptibilities between groups in rates of vancomycin-resistant enterococcus.

CONCLUSIONS

Topical vancomycin powder decreases the likelihood of gram-positive infections consistent with the biologic activity of vancomycin. Fewer methicillin-susceptible S. aureus and coagulase-negative Staphylococci infections were observed in the group treated with vancomycin powder. An effect of vancomycin powder on methicillin-resistant S. aureus infection risk was not detected given the low incidence in both the intrawound vancomycin and the standard-of-care groups. There was no emergence of gram-negative rod infections or increased resistance patterns observed. Use of topical vancomycin powder does not seem to produce infections in these patients with greater antibiotic resistance than would have occurred without its use.

LEVEL OF EVIDENCE

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

Skin Antisepsis before Surgical Fixation of Extremity Fractures

BACKGROUND

Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture).

METHODS

In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications.

RESULTS

A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups.

CONCLUSIONS

Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).

Predicting Which Species of Bacteria Will Cause an Infection After Fracture Surgery

The aim of this study was to develop and validate risk prediction models for deep surgical site infection (SSI) caused by specific bacterial pathogens after fracture fixation. A retrospective case-control study was conducted at a level I trauma center. Fifteen candidate predictors of the bacterial pathogens in deep SSI were evaluated to develop models of bacterial risk. The study included 441 patients with orthopedic trauma with deep SSI after fracture fixation and 576 control patients. The main outcome measurement was deep SSI cultures positive for methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S aureus (MRSA), gram-negative rods (GNRs), anaerobes, or polymicrobial infection within 1 year of injury. Prognostic models were developed for five bacterial pathogen outcomes. Mean area under the curve ranged from 0.70 (GNRs) to 0.74 (polymicrobial). Strong predictors of MRSA were American Society of Anesthesiologists (ASA) classification of III or greater (odds ratio [OR], 3.4; 95% CI, 1.6-8.0) and time to fixation greater than 7 days (OR, 3.4; 95% CI, 1.9-5.9). Gustilo type III fracture was the strongest predictor of MSSA (OR, 2.5; 95% CI, 1.6-3.9) and GNRs (OR, 3.4; 95% CI, 2.3-5.0). ASA classification of III or greater was the strongest predictor of polymicrobial infection (OR, 5.9; 95% CI, 2.7-15.5) and was associated with increased odds of GNRs (OR, 2.7; 95% CI, 1.5-5.5). Our models predict the risk of MRSA, MSSA, GNR, anaerobe, and polymicrobial infections in patients with fractures. The models might allow for modification of preoperative antibiotic selection based on the particular pathogen posing greatest risk for this patient population. [Orthopedics. 2024;47(1):e19-e25.].

The VANCO Trial Findings Are Generalizable to a North American Trauma Registry

OBJECTIVES

To estimate the generalizability of treatment effects observed in the VANCO trial to a broader population of patients with tibial plateau or pilon fractures.

METHODS

Design and Setting: Clinical trial data from 36 United States trauma centers and Trauma Quality Programs registry data from more than 875 Level I-III trauma centers in the United States and Canada.Patient Selection Criteria: Patients enrolled in the VANCO trial treated with intrawound vancomycin powder from January 2015 to June 2017 and 31,924 VANCO-eligible TQP patients admitted in 2019 with tibial plateau and pilon fractures.Outcome Measure and Comparisons: Deep surgical site infection and gram-positive deep surgical site infection estimated in the TQP sample weighed by the inverse probability of trial participation.

RESULTS

The 980 patients in the VANCO trial were highly representative of 31,924 TQP VANCO-eligible patients (Tipton generalizability index 0.96). It was estimated that intrawound vancomycin powder reduced the odds of deep surgical infection by odds ratio (OR) = 0.46 (95% confidence interval [CI] 0.25-0.86) and gram-positive deep surgical infection by OR = 0.39 (95% CI, 0.18-0.84) within the TQP sample of VANCO-eligible patients. For reference, the trial average treatment effects for deep surgical infection and gram-positive deep surgical infection were OR = 0.60 (95% CI, 0.37-0.98) and OR = 0.44 (95% CI, 0.23-0.80), respectively.

CONCLUSIONS

This generalizability analysis found that the inferences of the VANCO trial generalize and might even underestimate the effects of intrawound vancomycin powder when observed in a wider population of patients with tibial plateau and pilon fractures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Application of Bayesian Methods to Help Interpret the VANCO Trial Results

OBJECTIVE

To determine whether a Bayesian analysis changes the results of the VANCO trial.

DESIGN

A secondary analysis of a randomized clinical trial using Bayesian methods.

SETTING

Thirty-six US trauma centers.

PATIENTS

Patients ages 18-80 years with a tibial plateau or pilon fracture deemed high risk of infection and definitively treated with plate and screw fixation.

INTERVENTION

Patients were randomly allocated to receive 1000 mg of intrawound vancomycin powder at their definitive fixation or to a control group that received no topical antibiotics.

MAIN OUTCOME MEASUREMENTS

A deep surgical site infection requiring operative treatment within 6 months of definitive fixation. Secondary outcomes included gram-positive and gram-negative-only deep surgical site infections.

RESULTS

Of the 980 patients randomized, 874 (89%) had at least 140 days of follow-up and were included in this Bayesian analysis. The estimated probability that intrawound vancomycin powder reduces the risk of a deep surgical site infection is >98% [relative risk (RR), 0.66; 95% credible interval (CrI), 0.46-0.98]. There is a >99% chance intrawound vancomycin powder reduces gram-positive infections and an 80% chance the magnitude of this risk reduction exceeds 35% (RR, 0.52; 95% CrI, 0.33-0.84) exists. It is unlikely (44%) that intrawound vancomycin powder prevents gram-negative surgical site infections (RR, 1.06; 95% CrI, 0.48-2.45).

CONCLUSIONS

There is a high probability (>98%) that intrawound vancomycin powder reduces deep surgical site infections in patients with tibial plateau or pilon fractures at high risk of infection and even more likely it reduces deep infections with gram-positive pathogens (>99%).

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

POS1565-PARE ASSESSMENT OF QUALITY AND RELIABILITY OF YOUTUBE VIDEOS FOR PATIENT AND PHYSICIAN EDUCATION ON INFLAMMATORY MYOSITIS

Background

Nowadays 80% of internet users access health information online, with YouTube being the second most popular search website worldwide. This study was undertaken to assess the reliability and quality of videos pertaining to myositis on YouTube and identify lacunae in information material on the platform.

Objectives

This study aims to assess the quality and profile of myositis information videos on YouTube, and to compare and delineate attributes of useful and not useful videos using standard metrics.

Methods

A thorough search was carried out on YouTube using 9 search terms related to myositis. The inclusion criteria were primary English content related to myositis, acceptable audio-video quality, and multi-part videos to be considered as one, while duplicates and advertisements were excluded. The videos were classified as useful, not useful or misleading, and patient experiences (Figure 1).

Figure 1.

Flowchart of selection of YouTube videos for the study

Reliability of the videos was determined using the 5-point modified DISCERN (mDISCERN) criteria and quality by the 5-point Global Quality Scale (GQS) and 4-point JAMA scoring system. Score-based usefulness was defined as mDISCERN >4 or GQS >4 or JAMA >3. All values are in median and IQR.

Results

Of 453 analyzed videos 74% and 2% provided useful and not useful information respectively. 24% were patient experiences, and 324 (71%) were intended specifically for patients while 313 (69%) were for healthcare providers and students. Nearly one-thirds (n=143) reported information related to treatment of myositis.

Noteworthily, useful and not useful videos had similar views count. However, number of likes and daily viewership were higher for useful videos (p=0.024, p=0.046). Nearly half (47%) of useful videos were by professional medical societies/patient support groups while not useful ones were often by nonmedical media (38%).

Useful videos had higher mDISCERN reliability scores [4(3-4) vs 2(1-3), p<0.001] and better quality on GQS [4.5 (3.5-5) vs 1 (1-2.8), p<0.001] and JAMA [3 (3-4) vs 2.25 (2-3), p=0.004]. Physician predicted usefulness was discordant with score-based usefulness(κ=0.129). However, GQS score emerged significant (p=0.008) for predicting video usefulness in multivariate analysis (Table 1).

Table 1.

Factors predicting usefulness of video in binary logistic regression.

VariableB coefficientS.E.Exp (B) and 95% CIp valueIntended audience Anyone/General public-5.452.5860.004 (0.0-0.68)0.035Average GQS-2.861.0760.05 (0.007-0.47)0.008

GQS Global Quality Scale

. Exp (B) is odd’s ratio, p<0.05 is significant

Conclusion

Majority of English YouTube videos on myositis provide useful information for patients, largely related to treatment of myositis. However, the dynamic nature of YouTube could potentially change this equation in the future and physicians should correct any misinformation identified in face-to-face meetings or teleconsultations. High quality useful videos, often predicted by validated scores and produced by professional medical societies should be promoted as the first line of content consumed.

Disclosure of Interests

None declared

Does cumulative topical antibiotic powder use increase the risk of drug induced acute kidney injury in fracture patients?

AIMS

There is increasing evidence to support the use of topical antibiotics to prevent surgical site infections. Although previous research suggests a minimal nephrotoxic risk with a single dose of vancomycin powder, fracture patients often require multiple procedures and receive additional doses of topical antibiotics. We aimed to determine if cumulative doses of intrawound vancomycin or tobramycin powder for infection prophylaxis increased the risk of drug-induced acute kidney injury (AKI) among fracture patients.

METHODS

This cohort study was a secondary analysis of single-centre Program of Randomized Trials to Evaluate Pre-operative Antiseptic Skin Solutions in Orthopaedic Trauma (PREP-IT) trial data. We included patients with a surgically treated appendicular fracture. The primary outcome was drug-induced AKI. The odds of AKI per gram of vancomycin or tobramycin powder were calculated using Bayesian regression models, which adjusted for measured confounders and accounted for the interactive effects of vancomycin and tobramycin.

RESULTS

Of the 782 included patients (mean age 48 years (SD 20); 59% male), 83% (n = 648) received at least one vancomycin dose (cumulative range 1 to 12 g). Overall, 45% of the sample received at least one tobramycin dose (cumulative range 1.2 to 9.6 g). Drug-induced AKI occurred in ten patients (1.2%). No association was found between the cumulative dose of vancomycin and drug-induced AKI (odds ratio (OR) 1.08 (95% credible interval (CrI) 0.52 to 2.14)). Additional doses of tobramycin were associated with a three-fold increase in the adjusted odds of drug-induced AKI (OR 3.66 (95% CrI 1.71 to 8.49)). Specifically, the risk of drug-induced AKI rose substantially after 4.8 g of tobramycin powder (7.5% (95% CrI 1.0 to 35.3)).

CONCLUSION

Cumulative doses of vancomycin were not associated with an increased risk of drug-induced AKI among fracture patients. While the risk of drug-induced AKI remains less than 4% with three or fewer 1.2 g tobramycin doses, the estimated risk increases substantially to 8% after four cumulative doses. Level of evidence: Therapeutic Level III Cite this article: Bone Jt Open 2022;3(4):284-290.

Poor Agreement Between Next-Generation DNA Sequencing and Bacterial Cultures in Orthopaedic Trauma Procedures

BACKGROUND

Next-generation DNA sequencing (NGS) detects bacteria-specific DNA corresponding to the 16S ribosomal RNA gene and can identify bacterial presence with greater accuracy than traditional culture methods. The clinical relevance of these findings is unknown. The purpose of the present study was to compare the results from bacterial culture and NGS in order to characterize the potential use of NGS in orthopaedic trauma patients.

METHODS

A prospective cohort study was performed at a single academic, level-I trauma center. Three patient groups were enrolled: (1) patients undergoing surgical treatment of acute closed fractures (presumed to have no bacteria), (2) patients undergoing implant removal at the site of a healed fracture without infection, and (3) patients undergoing a first procedure for the treatment of a fracture nonunion who might or might not have subclinical infection. Surgical site tissue was sent for culture and NGS. The proportions of culture and NGS positivity were compared among the groups. The agreement between culture and NGS results was assessed with use of the Cohen kappa statistic.

RESULTS

Bacterial cultures were positive in 9 of 111 surgical sites (110 patients), whereas NGS was positive in 27 of 111 surgical sites (110 patients). Significantly more cases were positive on NGS as compared with culture (24% vs. 8.1%; p = 0.001), primarily in the acute closed fracture group. No difference was found in terms of the percent positivity of NGS when comparing the acute closed fracture, implant removal, and nonunion groups. With respect to bacterial identification, culture and NGS agreed in 73% of cases (κ = 0.051; 95% confidence interval, -0.12 to 0.22) indicating only slight agreement compared with expected chance agreement of 50%.

CONCLUSIONS

NGS identified bacterial presence more frequently than culture, but with only slight agreement between culture and NGS. It is possible that the increased frequency of bacterial detection with molecular methods is reflective of biofilm presence on metal or colonization with nonpathogenic bacteria, as culture methods have selection pressure posed by restrictive, artificial growth conditions and there are low metabolic activity and replication rates of bacteria in biofilms. Our data suggest that NGS should not currently substitute for or complement conventional culture in orthopaedic trauma cases with low suspicion of infection.

LEVEL OF EVIDENCE

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

Stepwise interventions for improving hand hygiene compliance in a level 3 academic neonatal intensive care unit in north India

OBJECTIVE

We evaluated effect of sequentially introducing four WHO-recommended interventions to promote hand-hygiene compliance in tertiary-care NICU.

STUDY DESIGN

Four dedicated research nurses directly observed doctors and nurses to record success in hand-hygiene opportunities at randomly selected NICU beds and randomly sampled time-slots in four phases (of 4-weeks each): I-Baseline, II-Self-directed learning; III-Participatory learning; IV-Closed-Circuit Television (CCTV); and V-CCTV-plus (with feedback).

FINDINGS

Hand-hygiene compliance changed from 61.8% (baseline) to 77% (end) with overall relative change: 24.6% (95% CI 18, 32; p value= 0.003); compared with preceding phase, relative changes of 21% (15, 28; <0.001), 4% (0, 8; 0.008), -10% (-13, -6; <0.001), and 10% (5, 15; <0.001) during phases II, III, IV, and V, respectively were observed. Rise in hand-hygiene compliance was higher for after-WHO-moments (12.7%; upto 2.5-folds for moment 5, <0.001) compared to before-WHO-moments (5.2%). Educational interventions, feedback and monitoring WHO moments can improve hand-hygiene compliance significantly among health-care providers in NICU.

Strength of Association between Infarct Volume and Clinical Outcome Depends on the Magnitude of Infarct Size: Results from the ESCAPE-NA1 Trial

BACKGROUND AND PURPOSE

Infarct volume is an important predictor of clinical outcome in acute stroke. We hypothesized that the association of infarct volume and clinical outcome changes with the magnitude of infarct size.

MATERIALS AND METHODS

Data were derived from the Safety and Efficacy of Nerinetide in Subjects Undergoing Endovascular Thrombectomy for Stroke (ESCAPE-NA1) trial, in which patients with acute stroke with large-vessel occlusion were randomized to endovascular treatment plus either nerinetide or a placebo. Infarct volume was manually segmented on 24-hour noncontrast CT or DWI. The relationship between infarct volume and good outcome, defined as mRS 0-2 at 90 days, was plotted. Patients were categorized on the basis of visual grouping at the curve shoulders of the infarct volume/outcome plot. The relationship between infarct volume and adjusted probability of good outcome was fitted with linear or polynomial functions as appropriate in each group.

RESULTS

We included 1099 individuals in the study. Median infarct volume at 24 hours was 24.9 mL (interquartile range [IQR] = 6.6-92.2 mL). On the basis of the infarct volume/outcome plot, 4 infarct volume groups were defined (IQR = 0-15 mL, 15.1-70 mL, 70.1-200 mL, >200 mL). Proportions of good outcome in the 4 groups were 359/431 (83.3%), 219/337 (65.0%), 71/201 (35.3%), and 16/130 (12.3%), respectively. In small infarcts (IQR = 0-15 mL), no relationship with outcome was appreciated. In patients with intermediate infarct volume (IQR = 15-200 mL), there was progressive importance of volume as an outcome predictor. In infarcts of > 200 mL, outcomes were overall poor.

CONCLUSIONS

The relationship between infarct volume and clinical outcome varies nonlinearly with the magnitude of infarct size. Infarct volume was linearly associated with decreased chances of achieving good outcome in patients with moderate-to-large infarcts, but not in those with small infarcts. In very large infarcts, a near-deterministic association with poor outcome was seen.

Risk factors for treatment failure of fracture-related infections

OBJECTIVE

Infection after fracture fixation is a potentially devastating outcome, and surgical management is frequently unsuccessful at clearing these infections. The purpose of this study is to determine if factors can be identified that are associated with treatment failure after operative management of a deep surgical site infection.

METHODS

We retrospectively reviewed the billing system at a Level I trauma center between March 2006 and December 2015. We identified 451 patients treated for deep surgical site infection after fracture fixation at our center. A multivariate regression analysis was then performed to evaluate for factors associated with treatment failure.

RESULTS

Mean follow-up was 2.3 years. One hundred fifty-six patients (35%) failed initial surgical management. Risk factors associated with treatment failure included initial culture results positive for polymicrobial organisms (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.0-2.4), removal of implants (OR, 1.9; 95% CI, 1.2-2.9), or Gustilo-Anderson IIIB/IIIC injury (OR, 2.0; 95% CI, 1.1-3.7). Increased body mass index and fulfilling the criteria to have a methicillin-resistant Staphylococcus aureus (MRSA) nasal swab screening showed a trend toward increased risk of failure.

CONCLUSION

Treatment failure after deep surgical site infection was relatively common. Three distinct factors (polymicrobial infection, removal of implants, and IIIB/C fracture) were associated with failure to eradicate the infection in the first series of surgeries and antibiotics. These data might help guide clinicians as they counsel patients on the risk of treatment failure and might focus efforts to improve treatment toward patients at higher risk of treatment failure.

Effect of Intrawound Vancomycin Powder in Operatively Treated High-risk Tibia Fractures: A Randomized Clinical Trial

Importance

Despite the widespread use of systemic antibiotics to prevent infections in surgically treated patients with fracture, high rates of surgical site infection persist.

Objective

To examine the effect of intrawound vancomycin powder in reducing deep surgical site infections.

Design, Setting, and Participants

This open-label randomized clinical trial enrolled adult patients with an operatively treated tibial plateau or pilon fracture who met the criteria for a high risk of infection from January 1, 2015, through June 30, 2017, with 12 months of follow-up (final follow-up assessments completed in April 2018) at 36 US trauma centers.

Interventions

A standard infection prevention protocol with (n = 481) or without (n = 499) 1000 mg of intrawound vancomycin powder.

Main Outcomes and Measures

The primary outcome was a deep surgical site infection within 182 days of definitive fracture fixation. A post hoc comparison assessed the treatment effect on gram-positive and gram-negative-only infections. Other secondary outcomes included superficial surgical site infection, nonunion, and wound dehiscence.

Results

The analysis included 980 patients (mean [SD] age, 45.7 [13.7] years; 617 [63.0%] male) with 91% of the expected person-time of follow-up for the primary outcome. Within 182 days, deep surgical site infection was observed in 29 of 481 patients in the treatment group and 46 of 499 patients in the control group. The time-to-event estimated probability of deep infection by 182 days was 6.4% in the treatment group and 9.8% in the control group (risk difference, -3.4%; 95% CI, -6.9% to 0.1%; P = .06). A post hoc analysis of the effect of treatment on gram-positive (risk difference, -3.7%; 95% CI, -6.7% to -0.8%; P = .02) and gram-negative-only (risk difference, 0.3%; 95% CI, -1.6% to 2.1%; P = .78) infections found that the effect of vancomycin powder was a result of its reduction in gram-positive infections.

Conclusions and Relevance

Among patients with operatively treated tibial articular fractures at a high risk of infection, intrawound vancomycin powder at the time of definitive fracture fixation reduced the risk of a gram-positive deep surgical site infection, consistent with the activity of vancomycin.

Trial Registration

ClinicalTrials.gov Identifier: NCT02227446.

Low Adherence to Recommended Guidelines for Open Fracture Antibiotic Prophylaxis

BACKGROUND

Prompt administration of antibiotics is a critical component of open fracture treatment. Traditional antibiotic recommendations have been a first-generation cephalosporin for Gustilo Type-I and Type-II open fractures, with the addition of an aminoglycoside for Type-III fractures and penicillin for soil contamination. However, concerns over changing bacterial patterns and the side effects of aminoglycosides have led to interest in other regimens. The purpose of the present study was to describe the adherence to current prophylactic antibiotic guidelines.

METHODS

We evaluated the antibiotic-prescribing practices of 24 centers in the U.S. and Canada that were participating in 2 randomized controlled trials of skin-preparation solutions for open fractures. A total of 1,234 patients were evaluated.

RESULTS

All patients received antibiotics on the day of admission. The most commonly prescribed antibiotic regimen was cefazolin monotherapy (53.6%). Among patients with Type-I and Type-II fractures, there was 61.1% compliance with cefazolin monotherapy. In contrast, only 17.2% of patients with Type-III fractures received the recommended cefazolin and aminoglycoside therapy, with an additional 6.7% receiving piperacillin/tazobactam.

CONCLUSIONS

There is moderate adherence to the traditional antibiotic treatment guidelines for Gustilo Type-I and Type-II fractures and low adherence for Type-III fractures. Given the divergence between current practice patterns and prior recommendations, high-quality studies are needed to determine the most appropriate prophylactic protocol.

Evaluation of Intra-Operative Topical Vancomycin and the Incidence of Acute Kidney Injury

Background: Intra-operative topical vancomycin (VAN) is a strategy used to prevent surgical site infections (SSI). Although evidence supporting efficacy in SSI prevention is evolving, data describing safety, specifically acute kidney injury (AKI), are limited. The purpose of this study was to determine AKI incidence in patients who received intra-operative topical VAN. Patients and Methods: This is a retrospective study of adult inpatient encounters in which topical VAN was administered intra-operatively as powder/paste, beads, rods/cement/spacers, or unspecified topical route from February to July 2018. Patients were excluded for AKI or renal replacement therapy (RRT) at baseline or ≤2 serum creatinine (SCr) values post-surgery. The primary outcome was AKI incidence after intra-operative topical VAN, defined as increase in SCr ≥50% or 0.5 mg/dL from baseline or RRT initiation. Secondary outcomes included analysis of AKI risk factors and SSI incidence. Acute kidney injury risk factors were analyzed using multivariable logistic regression. Results: Five hundred thirty-four patient encounters met study criteria. Powder/paste were the most common topical VAN formulations (44.8%) with median doses of 2,000 (range, 1,000-26,000) mg. Acute kidney injury incidence was 8.8%. Independent risk factors for AKI were higher Charlson comorbidity index (adjusted odds ratio [aOR], 1.20 [range, 1.06-1.36]), concomitant systemic VAN (aOR, 2.44 [range, 1.29-4.58]), and doubling of total topical VAN dose (aOR, 1.51 [range, 1.13-2.03]). Conclusions: The incidence of AKI with intra-operative topical VAN is comparable to reported rates as systemic VAN. Clinicians may consider total topical VAN dose and concomitant systemic VAN to limit AKI incidence with topical VAN use.

Effectiveness and safety of dolutegravir two-drug regimens in virologically suppressed people living with HIV: a systematic literature review and meta-analysis of real-world evidence

Objectives

Dolutegravir (DTG) is widely recommended within three‐drug regimens. However, similar efficacy and tolerability have also been achieved with DTG within two‐drug regimens in clinical trials. This study evaluated the real‐world effectiveness and discontinuations in people living with HIV‐1 (PLHIV) switching to DTG with lamivudine (3TC) or rilpivirine (RPV).

Methods

This was a one‐arm meta‐analysis utilizing data from a systematic literature review. Data from real‐world evidence studies of DTG + RPV and DTG + 3TC were extracted, pooled and analysed. The primary outcome was the proportion of patients with viral failure (VF; ≥ 50 copies/mL in two consecutive measurements and/or ≥ 1000 copies/mL in a single measurement) at week 48 (W48) and week 96 (W96). Other outcomes included virological suppression (VS; < 50 copies/mL) and discontinuations (W48 and W96). Estimates were calculated for VF, VS as per snapshot (VSS) and on treatment analysis (VSOT), and discontinuations.

Results

Pooled mean estimates of VF for DTG + 3TC and DTG + RPV were 0.8% [95% confidence interval (CI): 0.4–1.3] and 0.6% (95% CI: 0.0–1.6), respectively, at W48. VSS rate at W48 was 85.0% (95% CI: 82.3–87.5) for DTG + 3TC regimen and 92.4% (95% CI: 85.0–97.7) in the DTG + RPV regimen. The DTG + 3TC and DTG + RPV regimens led to discontinuations in 13.6% (95% CI: 11.1–16.2) and 7.2% (95% CI: 2.1–14.4) of patients, respectively, at W48. Similar results were observed at W96.

Conclusions

Treatment with DTG + 3TC or DTG + RPV in clinical practice provides a low rate of VF and a high rate of VS when initiated in virologically suppressed PLHIV with diverse backgrounds.

Adjuvant antibiotic-loaded bone cement: Concerns with current use and research to make it work

Antibiotic-loaded bone cement (ALBC) is broadly used to treat orthopaedic infections based on the rationale that high-dose local delivery is essential to eradicate biofilm-associated bacteria. However, ALBC formulations are empirically based on drug susceptibility from routine laboratory testing, which is known to have limited clinical relevance for biofilms. There are also dosing concerns with nonstandardized, surgeon-directed, hand-mixed formulations, which have unknown release kinetics. On the basis of our knowledge of in vivo biofilms, pathogen virulence, safety issues with nonstandardized ALBC formulations, and questions about the cost-effectiveness of ALBC, there is a need to evaluate the evidence for this clinical practice. To this end, thought leaders in the field of musculoskeletal infection (MSKI) met on 1 August 2019 to review and debate published and anecdotal information, which highlighted four major concerns about current ALBC use: (a) substantial lack of level 1 evidence to demonstrate efficacy; (b) ALBC formulations become subtherapeutic following early release, which risks induction of antibiotic resistance, and exacerbated infection from microbial colonization of the carrier; (c) the absence of standardized formulation protocols, and Food and Drug Administration-approved high-dose ALBC products to use following resection in MSKI treatment; and (d) absence of a validated assay to determine the minimum biofilm eradication concentration to predict ALBC efficacy against patient specific micro-organisms. Here, we describe these concerns in detail, and propose areas in need of research.

Vancomycin Powder Use in Fractures at High Risk of Surgical Site Infection

OBJECTIVES

To determine if the use of intrawound vancomycin powder reduces surgical-site infection after open reduction and internal fixation of bicondylar tibial plateau, tibial pilon, and calcaneus fractures.

DESIGN

Retrospective analysis.

SETTING

Level I trauma center.

PATIENTS

All fractures operatively treated from January 2011 to February 2015 were reviewed; 583 high-risk fractures were included, of which 35 received topical vancomycin powder. A previously published prospectively collected cohort of 235 similar high-risk fractures treated at our center from 2007 through 2010 served as a second comparison group.

INTERVENTION

Topical vancomycin powder at wound closure.

MAIN OUTCOME MEASUREMENTS

Deep surgical-site infection. Analyses used both univariate comparison of all patients and 1:2 matching analysis using both nearest neighbor and propensity-based matching.

RESULTS

Compared with a control group of fractures treated during the same time period without vancomycin powder, the infection rate with vancomycin powder was significantly lower [0% (0/35) vs. 10.6% (58/548), P = 0.04]. Compared with our previously published historical infection rate of 13% for these injuries, vancomycin powder was also associated with significantly decreased deep surgical-site infection (0% vs. 13%, P = 0.02). These results agreed with the matched analyses, which also showed lower infection in the vancomycin powder group (0% vs. 11%-16%, P ≤ 0.05).

CONCLUSIONS

Vancomycin powder may play a role in lowering surgical-site infection rates after fracture fixation. A larger randomized controlled trial is needed to validate our findings.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

130 Expression of selected biomarker candidate genes to confer invitro maturation in Indian buffaloes

Invitro maturation (IVM) of oocytes is a crucial step and is directly related to better embryo production in buffaloes. Therefore, we planned to study gene expression of GDF9, HAS2, SPRY1, ARHGAP22, COL18A1, and GPC4 genes in IVM and immature cumulus–oocyte complexes (COCs). The COCs were recovered from follicles of slaughter origin ovaries of native buffaloes. COCs were observed under stereo zoom microscope and categorized in four grades according to morphology. Of the four grades, the first three grade COCs were considered and randomly allotted in two groups: immature treatment group (n=263) and IVM treatment group (n=272). IVM of COCs was carried out in 100-μL drops of BO-IVM medium overlaying embryo tested oil in a 35-mm petri dish under 5% CO2 in a 39.0°C incubator for 24h. Cumulus of COCs of both groups were removed by treating with 0.25% trypsin, and oocytes were stored in RNALater for future use. The expression of genes was evaluated using quantitative PCR, and the relative expression of each gene was calculated using the ΔΔCt method with efficiency correction. The logarithmic transformation of fold change (log2FC) of each candidate gene in the IVM oocyte group was computed against the immature oocyte group based on the observed cycle threshold values. Appropriate standard deviations were determined based on the observed deviations among the triplicates. The expression in the IVM treatment group of previously reported upregulated genes (GDF9, HAS2, SPRY1) was higher (up to 10-fold) compared with the immature treatment group (reference group). In the present study, relatively lower expression was observed for the other candidate genes (ARHGAP22, COL18A1, GPC4) in the bovine transcripts of oocyte, which were previously also reported as being downregulated.

Obese patients and robotic colorectal surgery: systematic review and meta-analysis

BACKGROUND

Obesity is a major health problem, demonstrated to double the risk of colorectal cancer. The benefits of robotic colorectal surgery in obese patients remain largely unknown. This meta-analysis evaluated the clinical and pathological outcomes of robotic colorectal surgery in obese and non-obese patients.

METHODS

MEDLINE, Embase, Global Health, Healthcare Management Information Consortium (HMIC) and Midwives Information and Resources Service (MIDIRS) databases were searched on 1 August 2018 with no language restriction. Meta-analysis was performed according to PRISMA guidelines. Obese patients (BMI 30 kg/m2 or above) undergoing robotic colorectal cancer resections were compared with non-obese patients. Included outcome measures were: operative outcomes (duration of surgery, conversion to laparotomy, blood loss), postoperative complications, hospital length of stay and pathological outcomes (number of retrieved lymph nodes, positive circumferential resection margins and length of distal margin in rectal surgery).

RESULTS

A total of 131 full-text articles were reviewed, of which 12 met the inclusion criteria and were included in the final analysis. There were 3166 non-obese and 1420 obese patients. A longer duration of surgery was documented in obese compared with non-obese patients (weighted mean difference -21·99 (95 per cent c.i. -31·52 to -12·46) min; P < 0·001). Obese patients had a higher rate of conversion to laparotomy than non-obese patients (odds ratio 1·99, 95 per cent c.i. 1·54 to 2·56; P < 0·001). Blood loss, postoperative complications, length of hospital stay and pathological outcomes were not significantly different in obese and non-obese patients.

CONCLUSION

Robotic surgery in obese patients results in a significantly longer duration of surgery and higher conversion rates than in non-obese patients. Further studies should focus on better stratification of the obese population with colorectal disease as candidates for robotic procedures.

Effect of Extended Prophylactic Antibiotic Duration in the Treatment of Open Fracture Wounds Differs by Level of Contamination

OBJECTIVE

To determine the association between prophylactic antibiotic duration after the definitive wound closure of an open fracture and deep surgical site infection (SSI).

DESIGN

Retrospective cohort study.

SETTING

41 clinical sites in the United States, Canada, Australia, Norway, and India.

PARTICIPANTS

Patients (N = 2400) with open fractures of the extremities who participated in the Fluid Lavage of Open Wounds (FLOW) trial.

INTERVENTION

Extended antibiotic prophylaxis, defined as more than 72 hours of continuous antibiotic use after definitive wound closure.

MAIN OUTCOME MEASUREMENT

Deep SSI diagnosed within 1 year of enrollment.

RESULTS

Forty-two percent of participants received extended antibiotic prophylaxis. Deep SSI prevalence was 5%, 8%, and 23% for wounds with mild, moderate, and severe contamination, respectively. In open fractures with mild contamination, extended antibiotic use showed a trend toward increased odds [adjusted odds ratio (aOR) = 1.39; 95% confidence interval (CI), 0.92-2.11] of deep SSI compared with shorter use. No association was found among patients with moderate contamination (aOR = 1.09; 95% CI, 0.53-2.27). By contrast, extended antibiotic prophylaxis was strongly protective (aOR = 0.20; 95% CI, 0.07-0.60) against deep SSI in patients with severe contamination. Propensity score sensitivity analysis results were consistent with these findings.

CONCLUSIONS

The evidence suggests differential effects of extended postclosure antibiotic duration on SSI odds contingent on the degree of contamination in open fracture wounds. Although extended antibiotic duration resulted in lower odds of SSI among patients with severely contaminated wounds, we observed a trend toward higher odds of SSI in mildly contaminated wounds.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Remote wireless vital signs monitoring on the ward for early detection of deteriorating patients: A case series

INTRODUCTION

Remote wireless monitoring is a new technology that allows the continuous recording of ward patients' vital signs, supporting nurses by measuring vital signs frequently and accurately. A case series is presented to illustrate how these systems might contribute to improved patient surveillance.

METHODS AND RESULTS

Five hospitals in three European countries installed a remote wireless vital signs monitoring system on medical or surgical wards. Heart rate, respiratory rate and temperature were measured by the system every 2 min. Four cases of (paroxysmal) atrial fibrillation are presented, two cases of sepsis and one case each of pyrexia, cardiogenic pulmonary edema and pulmonary embolisms. All cases show that the remote monitoring system revealed the first signs of ventilatory and circulatory deterioration before a change in the trends of the respective values became obvious by manual vital signs measurement.

DISCUSSION

This case series illustrates that a wireless remote vital signs monitoring system on medical and surgical wards has the potential to reduce time to detect deteriorating patients.

450. Evaluation of Linezolid Pharmacokinetics in Obese Patients with Severe Skin and Soft-Tissue Infections

Background

Linezolid is an oxazolidinone antibiotic with broad activity against Gram-positive bacteria and serves as an option for treating severe skin and soft-tissue infections (SSTIs). Adult FDA-labeled dosing is fixed at 600 mg IV/PO twice daily. Although conflicting, current literature is suggestive that critically ill, obese patients require increased doses. Based on this literature, our institutional guidelines recommend linezolid 600 mg every 8 hours for patients ≥150 kg. This study aimed to determine whether obese patients receiving linezolid for severe SSTI attain pharmacokinetic/pharmacodynamic (PK/PD) targets.

Methods

Adult patients with a body mass index (BMI) ≥30 who were hospitalized and receiving IV linezolid were eligible for consent in this prospective cohort study. A severe SSTI was defined by one of the following: necrotizing fasciitis, myonecrosis, or SSTI with sepsis based on qSOFA score or SIRs criteria. Four blood samples were collected at steady state, after at least 3 linezolid doses, at 2, 4, and 6 hours after the dose and as a trough before the next dose. Linezolid serum concentrations were determined by HPLC. Non-compartmental methods in Phoenix-WinNonlin (Version 6.4) were used to estimate individual PK parameters. The PK parameters were used to determine the concentration-time profile assuming one-compartment kinetics. Target attainment was defined as achieving a 24-hour area under the curve (AUC_0–24)/minimum inhibitory concentration (MIC) ≥100 or time above the MIC ≥ 85%.

Results

Eleven patients were included in the study. The median BMI was 45.7 (34.6–72.7) and median total body weight was 141.3 kg (99.9–188). Necrotizing fasciitis was the most common SSTI type at 45.5%. Four patients received linezolid 600 mg every 8 hours, 3 patients of which were ≥150 kg. Two patients received renal replacement therapy at the time levels were drawn. Based on non-compartmental analysis, the mean AUC_0–24 was 208.1 hr*mg/L (± 85.3). All but one patient, who grew E. faecalis with a MIC of 2, met PK/PD targets based on AUC/MIC ≥100. All patients achieved concentrations above MIC for 100% of the dosing interval.

Conclusion

All patients met defined PK/PD targets with linezolid doses received. This study validates current institutional dosing guidelines for patients with severe SSTIs.

Disclosures

All authors: No reported disclosures.

2018 international consensus meeting on musculoskeletal infection: Summary from the biofilm workgroup and consensus on biofilm related musculoskeletal infections

Biofilm-associated implant-related bone and joint infections are clinically important due to the extensive morbidity, cost of care and socioeconomic burden that they cause. Research in the field of biofilms has expanded in the past two decades, however, there is still an immense knowledge gap related to many clinical challenges of these biofilm-associated infections. This subject was assigned to the Biofilm Workgroup during the second International Consensus Meeting on Musculoskeletal Infection held in Philadelphia USA (ICM 2018) (https://icmphilly.com). The main objective of the Biofilm Workgroup was to prepare a consensus document based on a review of the literature, prepared responses, discussion, and vote on thirteen biofilm related questions. The Workgroup commenced discussing and refining responses prepared before the meeting on day one using Delphi methodology, followed by a tally of responses using an anonymized voting system on the second day of ICM 2018. The Working group derived consensus on information about biofilms deemed relevant to clinical practice, pertaining to: (1) surface modifications to prevent/inhibit biofilm formation; (2) therapies to prevent and treat biofilm infections; (3) polymicrobial biofilms; (4) diagnostics to detect active and dormant biofilm in patients; (5) methods to establish minimal biofilm eradication concentration for biofilm bacteria; and (6) novel anti-infectives that are effective against biofilm bacteria. It was also noted that biomedical research funding agencies and the pharmaceutical industry should recognize these areas as priorities. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Laparoscopic repair of type III/IV giant para-oesophageal herniae with biological prosthesis: a single centre experience

PURPOSE

Repair of giant paraoesophageal herniae (GPEH) is technically challenging and requires significant experience in advanced foregut surgery. Controversy continues on suture versus mesh cruroplasty with the most recent systematic review and meta-analysis putting the onus on the operating surgeon. Study aim was to review whether the biological prosthesis (non-cross-linked bovine pericardium and porcine dermis) and the technique adopted for patients with GPEH had an influence on clinical and radiological recurrences.

METHOD

A retrospective analysis of a prospectively collected data of 60 consecutive patients with confirmed 5 cm hiatus hernia and ≥ 30% stomach displacement in the thorax that were operated in the upper gastrointestinal unit of a large district general hospital between September 2010 and August 2017. Pre and post-surgery Gastro-Oesophageal Reflux Disease Questionnaire [(GORD-HRQOL)] and a follow up contrast study were completed.

RESULTS

60 included 2 (3%) and 58 (97%) emergency and elective procedures respectively with a male: female ratio of 1:3, age 71* (Median) (42-89) years, BMI 29* (19-42) and 26 (43%) with ASA III/IV. Investigations confirmed 46* (37-88) mm and 42* (34-77) mm transverse and antero-posterior hiatal defect respectively with 60* (30-100)% displacement of stomach into chest. Operative time and length of stay was 180* (120-510) minutes and 2* (1-30) days respectively. One (2%) converted for bleeding and 2 (3%) peri-operative deaths. Five (8%), 5 (8%) and 4 (7%) have dysphagia, symptomatic and radiological recurrences respectively. GORD-HRQOL recorded preoperatively was 27* (10-39) dropping significantly postoperatively to 0* (0-21) (P < 0.005) with 95% patient satisfaction at a follow up of 60* (36-84) months.

CONCLUSIONS

Our technique of laparoscopic GPEH repair with biological prosthesis is safe with a reduced symptomatic and radiological recurrence and an acceptable morbidity and mortality.

In search of effective H1N1 neuraminidase inhibitor by molecular docking, antiviral evaluation and membrane interaction studies using NMR

Considering the need for discovery of new antiviral drugs, in view to combat the issue of resistance particularly to anti-influenza drugs, a series of 2'-amino, 3'-amino and 2', 4'-dihydroxy chalcone derivatives were designed. Structure-based drug design was used to design inhibitors of influenza virus - H1N1 neuraminidase enzyme. These were further optimized by a combination of iterative medicinal chemistry principles and molecular docking. Based on the best docking scores, some chalcone derivatives were synthesized and characterized by infrared spectroscopy (IR) and proton nuclear magnetic resonance (NMR). The molecules were evaluated for their anti-influenza action against influenza A/Pune isolate/2009 (H1N1) virus by in vitro enzyme-based assay (neuraminidase inhibition assay). We have then selected few of them for multinuclear NMR studies, 31P NMR, in order to probe the molecular mechanism of their antiviral action. Reasonably good correlation between docking scores; anti-influenza activity; and 31P NMR results were observed. The computational predictions were in consensus with the experimental results. It was observed that among tested compounds, derivative 1A, viz. 2', 4'-dihydroxy-4-methoxy chalcone, showed highest activity (IC50 = 2.23 μmol/l) against the virus under study. This derivative 1A can be explored further to provide a future therapeutic option for the treatment and prophylaxis of H1N1 viral infections.

Developing tool and Measuring Integration Characteristics of Basic Science Curriculum to Improve Curriculum Integration

Background Integrated curriculum enhances students' learning and the retention of knowledge. At Patan Academy of Health Sciences, integrated organ system based curriculum is used with Problem Based Learning as the principle teaching learning method to foster students' learning. In addition, other approaches of integration were under taken such as integrated assessment; logical arrangement teaching learning methods (lectures and practicals); joint effort of faculty in curriculum planning and delivery; conducive environment to foster hidden curriculum. This study describes the perception of faculty and students on integration characteristics of Basic Science curriculum. Objective To measure the integration characteristics of Basic Science Curriculum. Method Tool was developed to measure integration characteristics of Basic Science Curriculum and ensure whether such planned integration has been achieved. Mixed method was used to measure the perception of the integration characteristics i) quantitatively by questionnaire survey to faculty and students ii) qualitatively by in-depth interview of students. Result Both faculty and students perceived that all the blocks in Basic Science was well integrated in the quantitative questionnaire survey. But, in the in-depth interview, students perceived integration of curriculum in organ system blocks were better integrated compared to Principle of Human Biology blocks where fundamentals of basic science disciplines were delivered. Students reflected that Problem Based Learning not only integrated Basic Science disciplines but also with clinical sciences and the social context. But, students perceived that Community Health Sciences curriculum was not so well integrated with Basic Science subjects. Conclusion Overall, this study showed that planned integration in Basic Science curriculum was successfully executed during curriculum implementation.

Blazar spectral variability as explained by a twisted inhomogeneous jet

Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions-such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution-can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory.

Deposition and spatial variation of thoron decay products in a thoron experimental house using the Direct Thoron Progeny Sensors

Experiments have been carried out using the deposition-based Direct Thoron Progeny Sensors (DTPS) in a thoron experimental house. The objective was to study the thoron decay product characteristics such as the deposition velocities, spatial variability and dependence on aerosol particle concentrations. Since the deposition velocity is an important characteristic in the calibration of the DTPS, it is very important to study its dependence on aerosol concentration in a controlled environment. At low aerosol concentration (1500 particles/cm³) the mean effective deposition velocity was measured to be 0.159 ± 0.045 m h^-1; at high aerosol concentration (30 000 particles/cm³) it decreased to 0.079 ± 0.009 m h^-1. The deposition velocity for the attached fraction of the thoron decay products did not change with increasing aerosol concentration, showing measurement results of 0.048 ± 0.005 m h^-1 and 0.043 ± 0.014 m h^-1, respectively. At low particle concentration, the effective deposition velocity showed large scattering within the room at different distances from center. The attached fraction deposition velocity remained uniform at different distances from the wall. The measurements in the thoron experimental house can be used as a sensitivity test of the DTPS in an indoor environment with changing aerosol concentration. The uniform spatial distribution of thoron decay products was confirmed within the experimental house. This indicates that direct measurement of thoron decay product concentration should be carried out instead of inferring it from thoron gas concentration, which is very inhomogeneous within the experimental house.

Acute Transverse Myelitis Associated with Salmonella Bacteremia: A Case Report

Patient: Female, 28

Final Diagnosis: Acute transverse myelitis

Symptoms: Ascending paralysis

Medication: —

Clinical Procedure: —

Specialty: Infectious Diseases

Can applied external fixators be sterilized for surgery? A prospective cohort study of orthopaedic trauma patients

BACKGROUND

Temporary external fixators are often used to stabilize fractures when definitive fracture surgery must be delayed. Sometimes, external fixators are left in place during repeat operations, including definitive internal fixation of tibial pilon and tibial plateau fractures. It is unknown how well current surgical preparation sterilizes these devices, which become part of the surgical field. Our hypothesis was that our institution's standard surgical preparation creates a low rate of culture-positive environments on external fixators at the time of surgical skin incision.

METHODS

We prospectively consented and enrolled patients to obtain cultures (48 patients, 55 external fixators, 165 sets of culture data). After standard preparation and immediately before incision, cultures were obtained from three sites on each external fixator: 1) most distal pin 1cm from pin-skin interface, 2) most distal bar at midpoint between pin and clamp connectors, and 3) most distal clamp at bar-clamp interface. Our standard preparation for patients with external fixation in place is to don sterile gloves and wipe down all components of the external fixator with 70% alcohol-soaked sterile 4×4in gauze sponges before skin preparation. The skin and external fixator are then prepped in the usual fashion with ChloraPrep for closed wounds or with povidone iodine scrub and paint for open wounds. Swabs were processed and organisms from cultures identified. Clinicians were blinded to study results until study completion.

RESULTS

Two of 165 cultures (1.2%; 95% confidence interval [CI]: 0-2.9%) were positive for common pathogens sometimes observed in surgical site infection. Four cultures (2.4%; 95% CI: 0-4.8%) had pathogens that are rarely associated with surgical site infection, and four (2.4%; 95% CI: 0-4.8%) had nonpathogenic organisms.

CONCLUSION

Using 70% alcohol on external fixators plus either ChloraPrep for closed wounds or povidone iodine for open wounds seems to result in a low rate of positive cultures. Most species that were isolated are infrequently identified as sources of surgical site infections. This preparation protocol might be effective at producing a relatively clean environment at the time of surgery for patients with external fixators already in place.