An 11-Year-Long Analysis of the Risks Associated With Age in Patients Undergoing Anterior Cervical Discectomy and Fusion in a Large, Urban Academic Hospital.

STUDY DESIGN: A retrospective database study of patients at an urban academic medical center undergoing an Anterior Cervical Discectomy and Fusion (ACDF) surgery between 2008 and 2019. OBJECTIVE: ACDF is one of the most common spinal procedures. Old age has been found to be a common risk factor for postoperative complications across a plethora of spine procedures. Little is known about how this risk changes among elderly cohorts such as the difference between elderly (60+) and octogenarian (80+) patients. This study seeks to analyze the disparate rates of complications following elective ACDF between patients aged 60-69 or 70-79 and 80+ at an urban academic medical center. METHODS: We identified patients who had undergone ACDF procedures using CPT codes 22,551, 22,552, and 22,554. Emergent procedures were excluded, and patients were subdivided on the basis of age. Then each cohort was propensity matched for univariate and univariate logistic regression analysis. RESULTS: The propensity matching resulted in 25 pairs in both the 70-79 and 80+ y.o. cohort comparison and 60-69 and 80+ y.o. cohort comparison. None of the cohorts differed significantly in demographic variables. Differences between elderly cohorts were less pronounced: the 80+ y.o. cohort experienced only significantly higher total direct cost (P = .03) compared to the 70-79 y.o. cohort and significantly longer operative time (P = .04) compared to the 60-69 y.o. cohort. CONCLUSIONS: Octogenarian patients do not face much riskier outcomes following elective ACDF procedures than do younger elderly patients. Age alone should not be used to screen patients for ACDF.

A novel activated-zinc antiseptic solution effective against MRSA and Pseudomonas aeruginosa: a pig model.

OBJECTIVE: The purpose of this study was to investigate the antimicrobial efficacy of a novel activated zinc solution against meticillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa after one hour, and to evaluate any untoward effect of the solution on local wound tissue at 24 hours after solution exposure in a pig wound model. METHOD: A pathogen-free, commercially raised, Yorkshire-cross female pig was acquired 12 days prior to the procedure. Within one week prior to the procedure, a small loopful of test bacteria, Pseudomonas aeruginosa (pig-isolate) and MRSA (ATCC-6538), were streaked and cultured on a non-selective agar. Full-thickness wounds (n=24) were created and evenly divided into three groups: control wounds (exposed to bacteria but untreated, n=8); wounds treated with Compound 1 (n=8), and wounds treated with Compound 2 (n=8). All wounds were dressed and monitored for one hour and 24 hours. RESULTS: After one hour, the wounds treated with Compound 1 and Compound 2 had a mean recoverable total bacteria of 2.8 log colony forming units (CFUs) and 3.5 logCFUs, respectively. After one hour, the wounds treated with Compound 1 and Compound 2 had a mean recoverable MRSA of 2.3 logCFUs and 1.6 logCFUs, respectively (p=0.009). After one hour, the wounds treated with Compound 1 and Compound 2 had a mean recoverable Pseudomonas aeruginosa of 0.3 logCFUs and 0.0 logCFUs, respectively (p=0.000). After 24 hours of exposure to Compound 1 and Compound 2, there was no statistically significant increased necrosis (p=0.12, p=0.31, respectively) or neutrophilic infiltrate (Compound 2, p=0.12) when compared with control wounds. CONCLUSION: The novel activated-zinc compound used in this study demonstrated a 99.5-99.9% reduction in total bacteria, a 99.9-99.98% reduction in MRSA, and 100% eradication of Pseudomonas aeruginosa one hour after exposure. This novel solution may provide another significant tool to treat and/or prevent wound infections.

A Novel Activated Zinc Solution with Improved Efficacy Against Pseudomonas and MRSA Biofilm Compared to Chlorhexidine and Povidone-Iodine.

INTRODUCTION: The search for the optimal agent for infection eradication in periprosthetic joint infection (PJI) remains challenging as there are limited efficacious and safe options. The ideal solution should have significant bactericidal and anti-biofilm activity to be able to eradicate infection with the preservation of prosthetic components. Therefore, the purpose of this study was to 1) investigate the anti-biofilm efficacy of a novel activated zinc solution against Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) biofilm in vitro and 2) compare its efficacy against two leading commercially available antimicrobial irrigants (CHG and 0.35% povidone-iodine [PI]). MATERIALS AND METHODS: A modified Robbins device (MRD) was utilized to replicate Pseudomonas aeruginosa and MRSA biofilms. The primary outcome was to determine bacterial reduction after two hours of biofilm exposure to an activated zinc solution, CHG, and PI, and compare to untreated controls. RESULTS: Against Pseudomonas biofilm, activated zinc demonstrated a 4.5-log (99.996%) reduction, chlorhexidine demonstrated a 0.9-log (87.4%) reduction (p<0.001), and PI demonstrated a 0.8-log (83.1%) reduction (p<0.001). After two hours of exposure, activated zinc had undetectable MRSA with a 7.08-log (100%) reduction, chlorhexidine had a 1.9-log (98.7%) reduction (p<0.01), and PI had a 3.2-log (99.9%) reduction (p<0.01). CONCLUSIONS: Our novel activated zinc compound demonstrated a 99.996% reduction in Pseudomonas biofilm and a 100% reduction in MRSA biofilm. This novel solution may provide a significant tool in the arsenal to treat and/or prevent PJI and other wound infections. Future in vivo studies are warranted to demonstrate clinical utility, efficacy, and safety.

The Effect of Subsidence on Segmental and Global Lordosis at Long-term Follow-up After Anterior Cervical Discectomy and Fusion.

OBJECTIVE: Subsidence following anterior cervical discectomy and fusion (ACDF) may lead to disruptions of cervical alignment and lordosis. The purpose of this study was to evaluate the effect of subsidence on segmental, regional, and global lordosis. METHODS: This was a retrospective cohort study performed between 2016-2021 at a single institution. All measurements were performed using lateral cervical radiographs at the immediate postoperative period and at final follow-up greater than 6 months after surgery. Associations between subsidence and segmental lordosis, total fused lordosis, C2-7 lordosis, and cervical sagittal vertical alignment change were determined using Pearson correlation and multivariate logistic regression analyses. RESULTS: One hundred thirty-one patients and 244 levels were included in the study. There were 41 one-level fusions, 67 two-level fusions, and 23 three-level fusions. The median follow-up time was 366 days (interquartile range, 239-566 days). Segmental subsidence was significantly negatively associated with segmental lordosis change in the Pearson (r = -0.154, p = 0.016) and multivariate analyses (beta = -3.78; 95% confidence interval, -7.15 to -0.42; p = 0.028) but no associations between segmental or total fused subsidence and any other measures of cervical alignment were observed. CONCLUSION: We found that subsidence is associated with segmental lordosis loss 6 months following ACDF. Surgeons should minimize subsidence to prevent long-term clinical symptoms associated with poor cervical alignment.

The antimicrobial spectrum of Xeroform®.

INTRODUCTION/BACKGROUND: Xeroform® is a petrolatum-based fine mesh gauze containing 3% bismuth tribromophenate. Bismuth, similar to other metals, has antimicrobial properties. Xeroform® has been used for decades in burn and plastic surgery as a donor site dressing and as a covering for wounds or partial thickness burns. Despite this, the antimicrobial spectrum of Xeroform® remains largely unknown. We examined the in-vitro efficacy of Xeroform® against common burn pathogens using zone-of-inhibition methodology in a commercial research facility. METHODS/DESIGN: Pure strains of 15 common burn pathogens including Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin-sensitive Staphylococcus aureus (MSSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterobacter cloacae, Escherichia coli, Candida albicans, Vancomycin resistant Enterococcus, Acinetobacter baumennii, Klebsiella pneumonia, Extended spectrum beta-lactamase producing Klebsiella, Beta hemolytic Streptococcus pyogenes, Proteus mirabilis, Serratia marcescens, and Salmonella enterica ssp. Enterica were inoculated at a strength of 106-1010 CFU/ml onto appropriate agar plates. A sterile 1 in2 Xeroform® square was placed in the center of each plate, and the Zone of Inhibition (ZOI) was measured following 18-24h of incubation at 37°C. A second bismuth pharmaceutical (bismuth subsalicylate, Pepto-Bismol®) was then tested using the same methodology against the same strains of MRSA, MSSA, E. coli, K. pneumonia and S. marcescens. Finally, 3% w/v bismuth tribromophenate in glycerol suspension was tested against 13 burn pathogens for antimicrobial activity independent of the Xeroform® dressing by measure of Zone of Inhibition. RESULTS/FINDINGS: For Xeroform®, none of the fifteen pathogens had a measurable zone of inhibition on any plate. Bismuth subsalicylate showed a zone of inhibition for MSSA in 3 plates (mean of 47.2mm), in one of three plates for MRSA (13.8mm), and in one of three plates for S. marcesens (89.6mm). There was no zone of inhibition seen for K. pneumonia or E. coli. Bismuth tribromophenate, when not bound to Xeroform® showed activity against 12 of 13 pathogens. CONCLUSIONS/IMPLICATIONS: While bismuth subsalicylate, and bismuth tribromophenate unbound to Xeroform® demonstrate antimicrobial activity, it appears that Xeroform® dressings do not. The utility of Xeroform® in burn medicine may relate more to use as an impervious dressing than to antimicrobial effect. Donor sites are clean surgical wounds and clean partial thickness burns may have minimal colonization present. In such circumstances, an inactive and impervious dressing may be all that is necessary to promote wound healing.

Gentian Violet and Methylene Blue Polyvinyl Alcohol Foam Antibacterial Dressing as a Viable Form of Autolytic Debridement in the Wound Bed.

The objective of this article is to describe the results of a comparative porcine study that evaluated the effectiveness of a gentian violet and methylene blue (GV/MB) polyvinyl alcohol (PVA) antibacterial foam dressing in debriding eschar. The authors performed an in vivo, preclinical study on eschar-covered porcine wounds. Two clinical case studies are also included. Test products, GV/MB antibacterial foam dressing, collagenase ointment, collagenase ointment plus GV/MB antibacterial foam dressing, medical-grade honey, and moist gauze dressing (control), were applied to porcine wounds using a split-back study design. The percent of eschar removal and wound closure were measured and recorded at time points up to 14 days. Statistically significant reduction in eschar was observed with GV/MB dressing and with GV/MB dressing with collagenase. By day 14, the wounds with GV/MB dressing alone and GV/MB dressing with collagenase had eschar covering less than 25% of the wound bed area compared with collagenase alone, medical grade honey, or moist gauze control, which showed eschar still covering over 75% of the wound bed area. Autolytic debridement activity of GV/MB foam dressings was evident in the porcine eschar study, as well as in the cases described.

Reliability of surgeon-specific reporting of complications after colectomy.

OBJECTIVE: We sought to determine the reliability of surgeon-specific postoperative complication rates after colectomy. BACKGROUND: Conventional measures of surgeon-specific performance fail to acknowledge variation attributed to statistical noise, risking unreliable assessment of quality. METHODS: We examined all patients who underwent segmental colectomy with anastomosis from 2008 through 2010 participating in the Michigan Surgical Quality Collaborative Colectomy Project. Surgeon-specific complication rates were risk-adjusted according to patient characteristics with multiple logistic regression. Hierarchical modeling techniques were used to determine the reliability of surgeon-specific risk-adjusted complication rates. We then adjusted these rates for reliability. To evaluate the extent to which surgeon-level variation was reduced, surgeons were placed into quartiles based on performance and complication rates were compared before and after reliability adjustment. RESULTS: A total of 5033 patients (n = 345 surgeons) undergoing partial colectomy reported a risk-adjusted complication rate of 24.5%. Approximately 86% of the variability of complication rates across surgeons was explained by measurement noise, whereas the remaining 14% represented true signal. Risk-adjusted complication rates varied from 0% to 55.1% across quartiles before adjusting for reliability. Reliability adjustment greatly diminished this variation, generating a 1.2-fold difference (21.4%-25.6%). A caseload of 168 colectomies across 3 years was required to achieve a reliability of more than 0.7, which is considered a proficient level. Only 1 surgeon surpassed this volume threshold. CONCLUSIONS: The vast majority of surgeons do not perform enough colectomies to generate a reliable surgeon-specific complication rate. Risk-adjusted complication rates should be viewed with caution when evaluating surgeons with low operative volume, as statistical noise is a large determinant in estimating their surgeon-specific complication rates.

Geographic variability in potentially discretionary red blood cell transfusions after coronary artery bypass graft surgery.

OBJECTIVE: A number of established regional quality improvement collaboratives have partnered to assess and improve care across their regions under the umbrella of the Cardiac Surgery Quality Improvement (IMPROVE) Network. The first effort of the IMPROVE Network has been to assess regional differences in potentially discretionary transfusions (<3 units red blood cells [RBCs]). METHODS: We examined 11,200 patients undergoing isolated nonemergent coronary artery bypass graft surgery across 56 medical centers in 4 IMPROVE Network regions between January 2008 and June 2012. Each center submitted the most recent 200 patients who received 0, 1, or 2 units of RBC transfusion during the index admission. Patient and disease characteristics, intraoperative practices, and percentage of patients receiving RBC transfusions were collected. Region-specific transfusion rates were calculated after adjusting for pre- and intraoperative factors among region-specific centers. RESULTS: There were small but significant differences in patient case mix across regions. RBC transfusions of 1 or 2 units occurred among 25.2% of coronary artery bypass graft procedures (2826 out of 11,200). Significant variation in the number of RBC units used existed across regions (no units, 74.8% [min-max, 70.0%-84.1%], 1 unit, 9.7% [min-max, 5.1%-11.8%], 2 units, 15.5% [min-max, 9.1%-18.2%]; P < .001). Variation in overall transfusion rates remained after adjustment (9.1%-31.7%; P < .001). CONCLUSIONS: Delivery of small volumes of RBC transfusions was common, yet varied across geographic regions. These data suggest that differences in regional practice environments, including transfusion triggers and anemia management, may contribute to variability in RBC transfusion rates.

Keratinocyte overexpression of IL-17C promotes psoriasiform skin inflammation.

IL-17C is a functionally distinct member of the IL-17 family that binds IL-17 receptor E/A to promote innate defense in epithelial cells and regulate Th17 cell differentiation. We demonstrate that IL-17C (not IL-17A) is the most abundant IL-17 isoform in lesional psoriasis skin (1058 versus 8 pg/ml; p < 0.006) and localizes to keratinocytes (KCs), endothelial cells (ECs), and leukocytes. ECs stimulated with IL-17C produce increased TNF-α and KCs stimulated with IL-17C/TNF-α produce similar inflammatory gene response patterns as those elicited by IL-17A/TNF-α, including increases in IL-17C, TNF-α, IL-8, IL-1α/ß, IL-1F5, IL-1F9, IL-6, IL-19, CCL20, S100A7/A8/A9, DEFB4, lipocalin 2, and peptidase inhibitor 3 (p < 0.05), indicating a positive proinflammatory feedback loop between the epidermis and ECs. Psoriasis patients treated with etanercept rapidly decrease cutaneous IL-17C levels, suggesting IL-17C/TNF-α-mediated inflammatory signaling is critical for psoriasis pathogenesis. Mice genetically engineered to overexpress IL-17C in KCs develop well-demarcated areas of erythematous, flakey involved skin adjacent to areas of normal-appearing uninvolved skin despite increased IL-17C expression in both areas (p < 0.05). Uninvolved skin displays increased angiogenesis and elevated S100A8/A9 expression (p < 0.05) but no epidermal hyperplasia, whereas involved skin exhibits robust epidermal hyperplasia, increased angiogenesis and leukocyte infiltration, and upregulated TNF-α, IL-1α/ß, IL-17A/F, IL-23p19, vascular endothelial growth factor, IL-6, and CCL20 (p < 0.05), suggesting that IL-17C, when coupled with other proinflammatory signals, initiates the development of psoriasiform dermatitis. This skin phenotype was significantly improved following 8 wk of TNF-α inhibition. These findings identify a role for IL-17C in skin inflammation and suggest a pathogenic function for the elevated IL-17C observed in lesional psoriasis skin.

Study on the debridement efficacy of formulated enzymatic wound debriding agents by in vitro assessment using artificial wound eschar and by an in vivo pig model.

An in vitro efficacy study using newly developed artificial wound eschar (AWE) substrate was conducted for assessing enzyme dose response. The AWE substrate is prepared by the enzymatic conversion of fibrinogen to fibrin in the presence of collagen, fibrin, and elastin to form an insoluble planar matrix. AWE substrate was placed on Franz Diffusion Cells for continuously monitoring the debridement progress. A parallel in vivo study was performed using pig thermal-burn wounds. Papain at concentrations of 200, 400, 800, and 1,600 U/mg was used as the model debriding enzyme for both studies. The data from the first 5 hours of the in vitro testing showed that debriding activity increased as the enzyme concentration increased. The histological results of the in vivo biopsy samples showed that enzyme doses above 800 and 1,600 U/mg successfully achieved debridement on day 8, while lower treatment groups still contained eschar tissue. Using the histological measurement results (wound depth score) a dose response that correlated to the in vitro assessment was found. Granulation tissue maturity and reepithelialization displayed correlation with the enzyme dose. Results indicate that AWE substrate can be used to predict debridement efficacy in vitro when correlation to the in vivo assessment is achieved.

The impact of noncontact, nonthermal, low-frequency ultrasound on bacterial counts in experimental and chronic wounds.

Preventing wound infection and the development of resistant bacteria are important concerns in wound management. To determine if noncontact, nonthermal, low-frequency ultrasound therapy is effective in controlling wound bacterial colony counts, a series of four related experiments was conducted. First, ultrasound penetration in both wounded and intact skin was assessed in vitro. Compared to sham, noncontact ultrasound penetrated farther into both wounded (3 mm to 3.5 mm versus 0.35 mm to 0.50 mm) and intact (2.0 mm to 2.5 mm versus 0.05 mm to 0.07 mm, respectively) pig skin. Second, using an in vitro model to stain and count live/dead bacteria, 0% of sham treated and 33% of Pseudomonas aeruginosa, 40% of Escherichia coli and 27% of Enterococcus faecalis were dead after one ultrasound application. Minimal effects on methicillin-resistant Staphylococcus aureus and S. aureus were observed. Third, using an in vivo model, after 1 week, while differences between different bacterial species were observed, overall bacterial quantity decreased with ultrasound treatment (from 7.2 +/- 0.79 to 6.7 +/- 0.91 colony forming units per gram of tissue [CFU/g]) and silver antimicrobial dressings (from 7.2 +/- 0.79 to 5.7 +/- 0.6 CFU/g) but increased to 8.6 +/- 0.15 CFU/g for sham and 8.6 +/- 0.06 CFU/g for water-moistened gauze. Fourth, 11 patients (average age 60 years) with pressure ulcers containing bacterial counts >10(5) CFU/g of tissue received 2 weeks of noncontact ultrasound therapy. The quantities of seven bacterial organisms were reduced substantially from baseline to 2 weeks post treatment. None of the wounds exhibited signs of a clinical infection during the treatment period and no adverse events were observed. Taken together, these four studies indicate that noncontact ultrasound can be used to reduce bacterial quantity. Controlled clinical studies are warranted to ascertain the efficacy of this treatment and to further elucidate its effects on various Gram-negative and Gram-positive bacteria.

Influence of papain urea copper chlorophyllin on wound matrix remodeling.

The purpose of this study was to examine the dermal and epidermal alterations associated with wound healing in wounds treated with papain urea copper chlorophyllin (PUC), papain-urea, copper chlorophyllin, or urea base ointment and compare these with moist wound care using a porcine full-thickness infected wound model. All the wounds were evaluated postsurgery for erythema, transepidermal water loss, microscopic morphology, and changes in protein expression. Examination of stained paraffin sections revealed an increase in the number of keratinocytes present in the epidermis of the PUC and papain-treated pigs, relative to moist control. This increase in keratinocyte number corresponded to an increase in the movement of the keratinocytes into the underlying dermis in the form of rete pegs. In the dermis, there appeared to be an increase in blood vessel formation, collagen I deposition, and mature collagen in the papain and PUC treated tissues. The quality of healing appears to be enhanced based on the number of keratinocytes present in the epidermis, the extensive rete peg formation, the increase in vasculature, and the increase in collagen birefringence.