Infectious Complications After Modified Purse-String Stoma Closure.

Purpose: Current society guidelines recommend purse-string closure technique for stoma reversal, which has been shown to reduce but not eliminate the risk of deep surgical site infection (SSI) at the original stoma site, a complication associated with increased morbidity and cost. We studied an adjunctive technique to further reduce the risk of SSI. Methods: A retrospective chart review was conducted on adult patients who underwent stoma reversal between May 2016 - July 2022. Stoma reversal was performed with purse-string closure, and placement of a strip of povidone-iodine soaked non-adherent pad in the remaining two cm opening at the prior stoma site. This pad was taken out on post-operative day one and changed to wet-to-dry saline moistened gauze. Results: 82 patients were identified. The cohort had a median BMI 26.5 [IQR 23.0-31.0] and median age 57.5 [IQR 45.8-67.0]. Mean time from original surgery to reversal was nine months. 59.8% identified as female, 24.4% were currently smoking, 18.3% were had diabetes. The cohort experienced a 11.0% readmission rate and 18.3% rate of stoma site hernia with a mean follow up of 17 17 months. No patient developed an SSI. Conclusion: In this cohort study with known risk factors for SSI, no patients undergoing stoma reversal experienced a post-operative SSI. The adjunctive technique of a povidone-iodine soaked non-adherent pad in addition to purse-string closure should be further examined in conjunction with surgical bundles to reduce the risk of SSI and overall morbidity of stoma reversal surgery.

Duration of perioperative antibiotic prophylaxis in neonatal surgery: Less is more.

BACKGROUND: The ideal duration of neonatal antibiotic prophylaxis is not determined with wide variance in practice. This study aims to evaluate the association between duration of antibiotics and surgical site infection (SSI) in neonatal surgery. METHODS: A retrospective review regarding antibiotic prophylaxis was performed on <30-day-old surgical patients at a children's hospital from 2014 to 2019. The patients were analyzed based on demographics, presence of SSI, and antibiotic duration. The primary outcome was the development of SSI with ANOVA, chi-square, and recursive partitioning used for statistical analysis. RESULTS: 19/155 patients developed an SSI (12.26 â€‹%). Those with an SSI had a lower weight at surgery (p â€‹= â€‹0.03). Additionally, wound classification (p â€‹= â€‹0.17) and antibiotic duration >48hrs (p â€‹= â€‹0.94) made no statistical difference in SSI rate. The two variables most closely linked to SSI development were gestational age (100 â€‹%) and weight at time of procedure (80.76 â€‹%). CONCLUSIONS: Antibiotic prophylaxis >48 â€‹h did not decrease the incidence of SSI. Risk factors for SSI development in neonatal surgery were lower gestational age, decreased weight at time of procedure and total length of procedure.

The role of subcutaneous fat and BMI in predicting surgical outcomes and patient reported outcomes in robotic-assisted total hip arthroplasty.

Background: The purpose of this study was to assess if subcutaneous fat (SCF) or BMI is a predictor of surgical complications and patient reported outcomes in patients undergoing robotic-assisted total hip arthroplasty (THA). Methods: Patients who underwent robotic-assisted primary THAs at one institution between 2018 and 2020 were included in this retrospective cohort study. Prior to surgery, computed tomography (CT) was used to measure SCF in the posterolateral quadrant of the hip. SCF was measured 3 centimeters (cm) proximal to the greater trochanter (PGT) and 3 cm inferior to the distal tip of the greater trochanter (DGT).Measurements were normalized to the size of the patient's bony anatomy by dividing the subcutaneous fat area measurement by the transverse diameter of the femur 10 cm inferior to the tip of the greater trochanter. Patients were divided into quintiles determined by SCF distribution around the mean (groups 1-5) and BMI (BMI<25, BMI 25-29.9, BMI 30-34.9, BMI 35-39.9, and >40). Ninety day outcomes and PROMIS (Patient Reported Outcome Measures Information System) scores were acquired from the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database preoperatively, at 14-112 days post-operative and at the latest follow up. Results: There were 175 patients identified with a mean age of 63.83 years (range 27-89) and a mean BMI of 30.73kg/m2 (range 18.2-48.4). Interclass correlation coefficient was greater than 0.9 in all PGT, DGT, and GT measurements. Analysis of Variance (ANOVA) found there was a significantly shorter time from incision to closure in quintiles 1 and 3 when compared to the SCF quintile 5 (p<0.05) and that there was a significantly shorter time from incision to closure in BMI categories 1, 2, and 3 when compared to BMI category 5 (BMI > 40). There were no differences between SCF and BMI as predictive of length of stay, transfusion status, infection, or PROMIS scores. Conclusion: It can be concluded that hip SCF on axial CT images can reliably measure SCF and is predictive of time from incision to closure, but it does not show a significant difference in predicting the length of stay, infection, or PROMIS scores when compared to BMI.

From the Metaphor of the Lizard's Tail to That of the Doughnut: A Case of Achilles Tendon Complete Regrowth.

Introduction: Tendon tissue turnover is a very slow process. However, some tendons show very unique regeneration capabilities. The Achilles tendon regeneration and maturation process occurs uniformly and centripetally along the entire the length of the neo-tendon. Case Report: The present case report describes a complete regeneration of the Achilles tendon in a 54-year-old patient with a reinjury to the Achilles tendon following open tenorrhaphy surgery. The regenerative process had a positive outcome despite the patient suffering, at the time, from an infection caused by Cutibacterium acnes. Conclusion: This case report is a paradigmatic example of how the Achilles tendon is able to maintain its regenerative capacity even in extremely critical biological situations such as after an infection. However, the issue concerning the biological characteristics of the regenerated tendon remains open.

Association between Pre-operative Body Mass Index and Surgical Infection in Perihilar Cholangiocarcinoma Patients Treated with Curative Resection: A Multi-center Study.

Background: The objective of this study was to investigate the association between pre-operative body mass index (BMI) and surgical infection in perihilar cholangiocarcinoma (pCCA) patients treated with curative resection. Methods: Consecutive pCCA patients were enrolled from four tertiary hospitals between 2008 and 2022. According to pre-operative BMI, the patients were divided into three groups: low BMI (≤18.4 kg/m2), normal BMI (18.5-24.9 kg/m2), and high BMI (≥25.0 kg/m2). The incidence of surgical infection among the three groups was compared. Multivariable logistic regression models were used to determine the independent risk factors associated with surgical infection. Results: A total of 371 patients were enrolled, including 283 patients (76.3%) in the normal BMI group, 30 patients (8.1%) in the low BMI group, and 58 patients (15.6%) in the high BMI group. The incidence of surgical infection was significantly higher in the patients in the low BMI and high BMI groups than in the normal BMI group. The multivariable logistic regression model showed that low BMI and high BMI were independently associated with the occurrence of surgical infection. Conclusions: The pCCA patients with a normal BMI treated with curative resection could have a lower risk of surgical infection than pCCA patients with an abnormal BMI.

When Antimicrobial Treatment and Surgical Prophylaxis Collide: A Stewardship Opportunity.

Background: In 2002, the Centers for Medicare and Medicaid Services (CMS) in collaboration with the Centers for Disease Control and Prevention (CDC) established the Surgical Infection Prevention (SIP) project for the purposes of developing and standardizing quality improvement measures known to reduce the rates of post-operative surgical site infections (SSIs). Four years later the Surgical Care Improvement Project (SCIP), an expansion of SIP, was published in governmental Specifications Manual for National Inpatient Quality Measures and provided several additional initiatives applicable to the perioperative period. Central to both projects are the assurance of the timeliness, selection, and duration of peri-operative surgical prophylactic antibiotics. In support of this objective, various medical associations, such as the American Society of Health-System Pharmacists (ASHP) and the Infectious Diseases Society of America (IDSA), have developed the Clinical Practice Guidelines for Antimicrobial Prophylaxis in Surgery. To ensure compliance with quality measures, hospitals are required to report data to the Physicians Quality Reporting System, which is then reviewed by CMS for reimbursement purposes and to measure hospital performance. To maintain optimal standards of care and satisfy all core measures, it is expected that patients undergoing most categories of surgical procedures receive prophylactic antibiotics. We recognized that patients already being administered antimicrobial therapy as treatment for the condition requiring the surgery not uncommonly also were prescribed unwarranted and redundant pre-operative antibiotics. Our study was meant to quantify such antibiotic redundancy, which only risks the development of antimicrobial resistance and adverse events, to bolster our and other hospitals antimicrobial stewardship programs. Methods: A retrospective analysis of computerized hospital records over a one-month period of time (November 2022) was conducted focusing on hospital admissions that involved surgical operative procedures. Only those patients who had received a pre-operative surgical prophylactic antibiotic were included in the analysis. Results: Of the 92 surgeries that fulfilled the inclusion criteria, 38 (41.3%) were performed on patients who were already receiving therapeutic antibiotics for more than 24 hours targeted to treat the infection for which they were undergoing surgery. These included laparoscopic cholecystectomy (24), appendectomy (12), wound debridement (12), and soft tissue incision and drainage procedures (9), comprising nearly 50% of each type of these operations performed during the study time period. Conclusion: These findings demonstrate a clear opportunity to strengthen both our, and presumably other, hospitals antimicrobial stewardship programs. Together with physician education, granting the pharmacy the ability to cancel unnecessary and redundant surgical prophylactic antibiotics would conceivably be of great benefit.

Do preoperative glucose levels predict risk of complications in orthopaedic surgery?

PURPOSE: Post-operative hyperglycemia is a known risk factor for post-surgical complications. The predictive value of pre-operative blood glucose levels, however, is less understood. This study aimed to determine if pre-operative screening blood glucose levels affect the rate of post-operative infection or wound complications. We also investigated if case urgency or anatomic location alters this relationship. METHODS: A single-institution retrospective chart review was performed to evaluate patients treated between 2018 and 2021. Subjects ≥ 18 years with closed, non-infected orthopaedic diagnoses requiring surgery were included. Case urgency, demographics, comorbidities, blood glucose level within twelve h prior to surgery, and hemoglobin A1c level within 3 months of surgery, were collected. Infections and wound complications were recorded as outcomes. RESULTS: A total of 775 subjects with a mean age of 61 (range 18-96) were identified, including 543 elective and 232 trauma patients, with a mean pre-operative fasting glucose value of 127.7 mg/dL (range, 49-388 mg/dL) and average HbA1c of 6.9%. The odds of infectious complications were increased by a factor of 1.01 for every 1-point increase in blood glucose (95% CI 1.01-1.02; p < 0.01). CONCLUSIONS: Pre-operative blood glucose levels greater than 137 mg/dL were associated with an increase in wound complications, but not deep infections. Infection rates stratified by anatomic site and case urgency were not impacted by pre-operative glucose levels. The increased risk of poor wound healing in patients with pre-operative hyperglycemia demonstrates that day of surgery point-of-care blood glucose screening can be a useful risk stratification tool.

Acute Cholecystitis Due to Lactococcus lactis and Single-Center Experience With Infections Due to Lactococcus spp.

Background: Lactococcus species are used to ferment milk to yogurt, cheese, and other products. The gram-positive coccus causes diseases in amphibia and fish and is a rare human pathogen. Patients and Methods: A 51-year-old male underwent laparoscopic cholecystectomy for acute and chronic calculous cholecystitis. Lactococcus lactis was isolated from pus from his gallbladder empyema. Results: Our institutional database was searched for other cases of Lactococcus spp. infections and four patients (2 males, 2 females; aged 51, 64, 78, and 80 years) were identified during a four-year period. The three other patients had positive blood cultures associated with pneumonia, toxic megacolon, and severe gastroenteritis. All isolates were monocultures with Lactococcus lactis (2), Lactococcus garvieae (1) and Lactococcus raffinolactis (1). Two patients died related to their sepsis. We report the second case of cholecystitis involving Lactococcus. Conclusions: Lactococcus is a very rare pathogen mainly causing blood stream infections but needs to be considered to cause serious surgical infections in humans.

Controlled release of vancomycin from PEGylated fibrinogen polyethylene glycol diacrylate hydrogel.

Surgical site infection (SSI) is a common issue post-surgery which often prolongs hospitalization and can lead to serious complications such as sternal wound infection following cardiac surgery via median sternotomy. Controlled release of suitable antibiotics could allow maximizing drug efficacy and safety, and therefore achieving a desired therapeutic response. In this study, we have developed a vancomycin laden PEGylated fibrinogen-polyethylene glycol diacrylate (PF-PEGDA) hydrogel system that can release vancomycin at a controlled and predictable rate to be applied in SSI prevention. Two configurations were developed to study effect of the hydrogel on drug release, namely, vancomycin laden hydrogel and vancomycin solution on top of blank hydrogel. The relationship between the rigidity of the hydrogel and drug diffusion was found to comply with a universal power law, i.e., softer hydrogels result in a greater diffusion coefficient hence faster release rate. Besides, vancomycin laden hydrogels exhibited burst release, whereas the vancomycin solution on top of blank hydrogels exhibited lag release. A mathematical model was developed to simulate vancomycin permeation through the hydrogels. The permeation of vancomycin can be predicted accurately by using the mathematical model, which provided a useful tool to customize drug loading, hydrogel thickness and stiffness for personalized medication to manage SSI. To evaluate the potential of hydrogels for bone healing applications in cardiovascular medicine, we performed a proof-of-concept median sternotomy in rabbits and applied the hydrogels. The hydrogel formulations accelerated the onset of osteo-genetic processes in rabbits, demonstrating its potential to be used in human.

The Impact of Redosing Antibiotics for Pediatric Patients Undergoing Appendectomy for Complicated Appendicitis.

Currently, there is no universally accepted, standardized protocol for pre-operative antibiotic administration in the setting of appendectomy for complicated appendicitis among pediatric patients. Strategies to mitigate surgical site infections (SSIs) must be balanced with optimal antibiotic use and exposure. We conducted a retrospective chart review to compare outcomes between patients treated pre-operatively with a single pre-operative dose of antibiotics with those who received additional antibiotics prior to laparoscopic appendectomy for complicated appendicitis between 2020 and 2022. Of 124 pediatric patients, 18% received an additional dose of pre-operative antibiotics after initial treatment dose. Surgical site infection rates between the two groups were not statistically significant (P-value = .352), thereby suggesting that redosing antibiotics closer to the time of incision may not impact SSI rates. Additional studies are necessary to make clinical recommendations.

Impact of the 4th of August Beirut explosion mass casualty incident on a university hospital microbial Flora.

BACKGROUND: Following the Beirut explosion, our university hospital received at least 350 casualties. Subsequently, infection control standard practices were compromised. Concerns for Multi-Drug Resistant Organisms (MDROs) infections in injured patients and a resulting hospital outbreak were raised. The objectives of the study were to compare the rate of hospital growing MDROs 6 months before and 6 months after the Beirut explosion, to identify emerging microorganisms and to evaluate the change in surgical infection prevention practices. METHODS: This is a retrospective chart review of patients with hospital acquired infections (HAI) admitted to the hospital before and after the Beirut explosion. The study was conducted between February 4, 2020 and January 4, 2021. Excluded patients were those transferred from other hospitals and those with community acquired infections. The primary outcome was to identify the rate of growing MDROs post explosion. The secondary outcomes were identifying antibiotics used for surgical prophylaxis in patients requiring surgeries and patients diagnosed with a HAI. Therefore, patients were divided in three groups. Control group included patients admitted with explosion-related injuries on that same day. Patients admitted and between February 4 and August 4 and diagnosed with HAI were compared to those admitted post August 4 with explosion-related HAI and to patients diagnosed with non-explosion-related HAI between August 4 and January 4, 2021. An estimated rate of 18-22% MDRO was needed to achieve a statistical significance with 80% power and 0.05 α. Pearson Chi square test was used to analyze the primary outcome. RESULTS: A total of 82 patients with 150 cultures were included in this study. Data showed an increase in the rate of MDRO after the explosion with 37.1% of the cultures taken before the explosion and 53.1% after the explosion (p = 0.05). When comparing the types of HAI in both groups, culture sites were significantly different between pre- and post-explosion patients (p = 0.013). However, both groups had similar types of microbes (p = 0.996) with an increase in candida related infections. CONCLUSION: These findings confirmed that the Beirut explosion impact on antimicrobial resistance was similar to combat zone incidence, where an increase in MDROs rate such as Escherichia coli (E.Coli) and Stenotrophomonas maltophilia, in addition to the increase in candida related infections.

In Vitro Evaluation of Vancomycin-Induced Toxicity in Human Primary Knee Chondrocytes.

Septic arthritis as a complication of orthopaedic joint surgery can have catastrophic outcomes for patients. To minimise infection risk associated with elective orthopaedics, topical vancomycin during surgery has become increasingly common. Evidence suggests that high concentrations of vancomycin, following direct application of the drug to the joint, are toxic towards various local cell types in the joint, including chondrocytes. However, the mechanism of this vancomycin tissue toxicity is yet to be determined. The aim of this study was to evaluate the toxicity of vancomycin on chondrocytes and the mechanisms of cell death involved. Human primary knee chondrocytes were exposed to vancomycin (1.25-10 mg/mL) for 24 h and their viability assessed using the resazurin reduction assay in vitro. Specific cell death mechanisms and their contributors, including reactive oxygen species (ROS) production and apoptosis, were measured. This study showed that high concentrations of vancomycin (5 and 10 mg/mL) were toxic towards human primary knee chondrocyte cells, while lower concentrations (1.25 and 2.5 mg/mL) were not. Cell death studies found that this occurred through an apoptotic pathway. This study provides additional support that vancomycin in high doses is toxic towards chondrocytes and preliminary evidence that this toxicity occurs via apoptotic cell death mechanisms.

Assessing Second Debridement Timing and Mortality in Necrotizing Soft Tissue Infections.

BACKGROUND: Patients with necrotizing soft tissue infection undergo an average of 4-5 debridements per hospital admission. Optimal timing for initial debridement is emergent. Second debridement is universally recommended to occur within 24 hours of the first, but no studies have successfully evaluated this time frame. Prior work has suggested that delays in second debridement are associated with increased mortality, and that few patients receive second debridement within 24 hours. METHODS: We performed a retrospective cohort study at a single center from 01/01/08 to 09/01/2021. The explanatory variable was whether the subject received second debridement within 24 hours of initial debridement. The primary outcome was in-hospital mortality. Baseline characteristics were collected. Subjects were stratified into 2 groups by time between first and second debridement: <24 and ≥24 hours. Variables were compared using Fisher's exact and Wilcoxon rank-sum tests. RESULTS: 77 patients met inclusion criteria. The median overall time to second debridement was 40 hours. 12 subjects received second debridement within 24 hours (15.6%). There was no difference in in-hospital mortality between the <24 (n = 3, 25.0%) and ≥24-hour second debridement groups (n = 4, 6.2%; P = .07). The 2 groups did not differ by secondary outcomes, including total number of debridements, ICU LOS, or wound closure. CONCLUSION: No difference in mortality was observed between subjects undergoing second debridement within 24 vs after 24 hours. Only 16% of subjects received second debridement within the recommended 24-hour time interval. Further study is required to identify the optimal timing of second debridement.

Adverse Events of Surgical Drain Placement: An Analysis of the NSQIP Database.

BACKGROUND: Surgical site drainage is important to prevent hematoma, seroma, and abscess formation. However, the placement of drain placement also predispose patients to several postoperative complications. The aim of this study is to clarify the risk-benefit profile of surgical drain placement. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Procedure-Targeted Databases were used to identify patients who underwent hepatectomy, pancreatectomy, nephrectomy, cystectomy, and prostatectomy. Patients who underwent each procedure were divided into 2 groups based on intraoperative drain placement. Propensity score-matched cohorts of these 2 groups were compared in terms of postoperative adverse events, readmission, reoperation, and length of stay. RESULTS: Hepatectomy patients with drains experienced organ space infections (P < .001), sepsis (P < .001), and readmission (P = .021) more often than patients without drains. Patients who underwent pancreatectomy and had drains placed experienced wound dehiscence less frequently than those without drains (P = .04). For hepatectomy, pancreatectomy, nephrectomy, and prostatectomy populations, patients with drains had longer lengths of stay (P < .05). Matched populations across all procedures did not differ in terms of reoperation rate. DISCUSSION: Prophylactic surgical drain placement may be associated with increased infectious complications and prolonged length of stay. Further studies are needed to elucidate the complete adverse event profile of surgical drains. Nonetheless, outcomes may be improved with better patient selection or advancements in drain technology.

Pediatric Ultrasound Appendicitis Score for the Diagnosis of Acute Appendicitis to Reduce Computed Tomography Scan Utilization.

BACKGROUND: Acute appendicitis is one of the most common reasons for pediatric surgical consultation in the emergency room. Although acute appendicitis is a clinical diagnosis, the use of imaging in the emergency department to assist with the diagnosis is very common. Ultrasound is frequently utilized in pediatrics because of the radiation risks associated with computed tomography (CT) scan. The risks of radiation in the pediatric population are much more significant than in adults. Reasons for this include smaller size so there is a relative higher radiation dose than for larger adults, radiosensitive organs such as thyroid, bone marrow, and gonads, and radiation exposure earlier in life allows for more time that a radiation induced cancer could develop. The risks of radiation from imaging are increased with cumulative dosing. METHODS: The purpose of this study was to incorporate the pediatric appendicitis score (PAS) and standardized ultrasound scoring system to provide a combined score that would assist with the clinical diagnosis of acute appendicitis and avoid the need for a CT scan. RESULTS: The presented data shows that for scores of 7 or more, the specificity and sensitivity is 90% and 90.2%, respectively for the diagnosis of acute appendicitis. DISCUSSION: This study validates the combined score, shows the specific cutoffs, and initiates the discussion that CT scan may not always be required for diagnosing acute appendicitis if this scoring system is used.

A Pathway for Increased Diversity, Equity, and Inclusion in the Surgical Infection Society.

Background: With the rise of diversity, equity, and inclusion (DEI) efforts across medicine, the Surgical Infection Society (SIS) leadership undertook a several-year mission to evaluate DEI issues within the SIS, through the formation of a DEI Ad Hoc Committee to guide the application of best practices. The purpose of this article is to describe the work of the DEI committee since its inception, as well as report on advances made during that time. Methods: Beginning in September 2020, 26 volunteer committee members met monthly to explore the current state of science and best practices around DEI, identify opportunities for the SIS, and translate opportunities into recommendations. As part of this initiative, a survey of the SIS membership was conducted. Survey results, published best practices from business and medicine, and experiences of committee members were utilized collaboratively to outline specific opportunities and recommendations. These findings were presented to the SIS Executive Council and to the membership at the SIS Annual Business Meeting. Results: Committee-identified opportunities and recommendations fell into broad categories of Membership, Leadership and Society Structure, the Annual Meeting, and Research Priorities. Several recommendations were immediately enacted, and a standing DEI committee was established to continue this work. Conclusions: Beyond the main mission of the SIS to advance the science of surgical infections, the SIS can also have a major impact on DEI within society and academic surgery at large.

Reduction of methicillin-resistant Staphylococcus aureus biofilm growth and development using arctic berry extracts.

Introduction: Surgical site infection remains a devastating and feared complication of surgery caused mainly by Staphylococcus aureus (S. aureus). More specifically, methicillin-resistant S. aureus (MRSA) infection poses a serious threat to global health. Therefore, developing new antibacterial agents to address drug resistance are urgently needed. Compounds derived from natural berries have shown a strong antimicrobial potential. Methods: This study aimed to evaluate the effect of various extracts from two arctic berries, cloudberry (Rubus chamaemorus) and raspberry (Rubus idaeus), on the development of an MRSA biofilm and as treatment on a mature MRSA biofilm. Furthermore, we evaluated the ability of two cloudberry seed-coat fractions, hydrothermal extract and ethanol extract, and the wet-milled hydrothermal extract of a raspberry press cake to inhibit and treat biofilm development in a wound-like medium. To do so, we used a model strain and two clinical strains isolated from infected patients. Results: All berry extracts prevented biofilm development of the three MRSA strains, except the raspberry press cake hydrothermal extract, which produced a diminished anti-staphylococcal effect. Discussion: The studied arctic berry extracts can be used as a treatment for a mature MRSA biofilm, however some limitations in their use exist.

Hydrogen Peroxide, Povidone-Iodine and Chlorhexidine Fail to Eradicate Staphylococcus aureus Biofilm from Infected Implant Materials.

Hydrogen peroxide, povidone-iodine, and chlorhexidine are antiseptics that are commonly added to irrigants to either prevent or treat infection. There are little clinical data available that demonstrate efficacy of adding antiseptics to irrigants in the treatment of periprosthetic joint infection after biofilm establishment. The objective of the study was to assess the bactericidal activity of the antiseptics on S. aureus planktonic and biofilm. For planktonic irrigation, S. aureus was exposed to different concentrations of antiseptics. S. aureus biofilm was developed by submerging a Kirschner wire into normalized bacteria and allowing it to grow for forty-eight hours. The Kirschner wire was then treated with irrigation solutions and plated for CFU analysis. Hydrogen peroxide, povidone-iodine, and chlorhexidine were bactericidal against planktonic bacteria with over a 3 log reduction (p < 0.0001). Unlike cefazolin, the antiseptics were not bactericidal (less than 3 log reduction) against biofilm bacteria but did have a statistical reduction in biofilm as compared to the initial time point (p < 0.0001). As compared to cefazolin treatment alone, the addition of hydrogen peroxide or povidone-iodine to cefazolin treatment only additionally reduced the biofilm burden by less than 1 log. The antiseptics demonstrated bactericidal properties with planktonic S. aureus; however, when used to irrigate S. aureus biofilms, these antiseptics were unable to decrease biofilm mass below a 3 log reduction, suggesting that S. aureus biofilm has a tolerance to antiseptics. This information should be considered when considering antibiotic tolerance in established S. aureus biofilm treatment.

Combined Interventional Radiology and Surgical Cut-Down Approaches for Retained Gallstones.

Symptomatic retained gallstones are a rare but potentially morbid condition. Post-cholecystectomy patients presenting with vague complaints or perihepatic abscesses should be considered for retained gallstones. Traditional treatment was incision and drainage or exploratory laparotomy with washout. The current standard is minimally invasive procedures. In this case report, two different and unpublished combination methods between surgery and interventional radiology were used to extract retained stones. The first patient underwent needle-wire localization pre-operatively to identify the retained stone. The surgeon cut down along the wires and excised the stone. The second patient had a 10 French drain placed to drain the abscess surrounding the stone. The surgeon cut down along the drain, as the drain's pigtail and retained stone were located in the abscess cavity. Based on this case report, we propose using the successful method of combined interventional radiology and general surgery procedures to excise larger and deeper retained dropped gallstones.