Primary prevention of surgical site infection: an antibiotic timing pilot

Authors:
Alicia C. Speak, Annmarie Vilkins, Arielle Gupta, Anita B Shallal, Trevor Szymanski, Abigail Ruby, Eman Chami

Body of Abstract:
Background:  

Surgical site infections (SSI) are the most common complications of gynecologic procedures. Risk factors for SSI include surgical site, type and duration of surgery, and patient risk factors. Surgical infection prophylaxis (SIP) is a core strategy employed to reduce SSI, and the timing of antibiotics is of critical importance. Clinical guidelines recommend the use of cefazolin within 60 minutes of surgical incision. Following an observed increase in SSI standardized infection ratio (SIR) for gynecologic surgeries at our institution, a multi-disciplinary collaborative effort for antibiotic timing was introduced.  

Methods: 

This was an IRB exempt, single pre-test, post-test quasi-experiment at a single institution. All gynecologic cases between 1/1/2025-11/6/2025 requiring antibiotic prophylaxis per consensus guidelines were included. The intervention was introduced on 8/20/2025, where antibiotics were initiated on arrival to the operating room or at pre-induction time out if not already done. This was achieved through education roll-out to key stakeholders, including gynecology, anesthesia, and nursing teams.  The primary endpoint was the timing of cefazolin SIP post-intervention, and secondary endpoint was the number of SSI cases post-intervention. A chi-square test of independence was conducted to examine the effect of the intervention on time to antibiotic administration, and Cramer’s V was calculated to measure the strength of association. “Ideal” antibiotic timing was defined as receiving antibiotics within 31-60 minutes pre-incision. 

Results:  

232 total cases were identified, including 183 pre-intervention and 44 post-intervention.   There was a statistically significant difference in the number of patients who received ideal antibiotic timing for cefazolin in the post-intervention group (24; 54.4% compared to 43; 23.5% pre-intervention; p<0.005) [Figure 1]. In the pre-intervention group, 9 (4.92%) surgical site infections were identified, versus 0 (0.00%) in the post infection group.   Conclusions:   Improving the timing of SIP had a significant impact on our rates of SSI in gynecological operations, showing the importance of a multi-disciplinary approach on infection prevention in surgical patients. Following an educational roll-out with key stakeholders, antibiotics were significantly more likely to be given within an ideal timeframe. Our study is limited by the small number of post-intervention SSI, making interpretation difficult. There were also additional concomitant interventions (including re-training on appropriate scrub and abdominal preparation technique), that may confound these results and likely also contributed to decreased SSI rates.

Room Air Quality Monitoring Misses Surgical Field Exposure: Rethinking Ventilation Standards for Surgical Site Infection (SSI) Prevention

Authors:
Justin Benton, Divya Kewalramani, Lily Wushanley, Oluwaseun Adeyemi, Alexander Wurtz, Yana Chaudharu, Les Barta, Joelle Getrajman, Leonardo Calderone, Keith Kaye, Brian Buckley, Gediminas Mainelis, Philip Barie, Mayur Narayan

Body of Abstract:
Background: Intraoperative airborne particulate matter (PM), of which electrosurgical smoke is a major constituent, serves as the primary vector for exogenous microbial delivery to surgical incisions. Yet current gold-standard ventilation strategies show inconsistent effectiveness in reducing surgical site infections (SSIs). These strategies assume operating room (OR) air quality (measured at entry points for ventilation compliance) reflects surgical field exposure (where pathogens contact open incisions). This assumption remains untested. We hypothesized that electrosurgical smoke exposure varies by measurement location.

Methods: In an OR with active laminar airflow ventilation (≥20 air changes/h, high efficiency particulate air filtration,) we performed electrocautery activations on draped cadaver arms under aseptic technique. Synchronized PM sensors (1-Hz resolution, 0.1–10.0 μm) were positioned field-proximal (L1: 1m from surgical site, 1m height, 4m from door) and at room-entry (L2: 1m from door, 1m height, 3m from surgical site). Following 10-minute baselines, electrocautery (without smoke evacuation) was activated in repeated 5-second ON/180-second OFF cycles on cadaver tissue. We compared simultaneous sensor measurements using paired Wilcoxon tests for magnitude and timing differences, Cohen’s kappa for extreme event agreement (>50 μg/m³), and Spearman correlation for magnitude-dependent spatial discordance (α=0.05).

Results: Across 151 paired cycles, peak concentrations differed between locations (median difference 3.0 μg/m³, Interquartile range [IQR] 0.5–8.0 μg/m³; p<0.0001), with L1 measuring higher in 75% of cycles. Peak timing varied (median 9 sec, range: -17.5-69.5 seconds; p=0.0009), with L2 peaks occurring first in 40% of cycles and later in 60% of cycles. Extreme PM spikes (>50 μg/m³) showed poor spatial agreement (κ=0.13): only 2/12 extreme events was detected by both sensors simultaneously, with 10 events recorded at L1 while L2 remained at baseline (<2 μg/m³). Spatial discordance increased systematically with event magnitude (ρ=0.889, p<0.0001), with the largest events showing up to 198-fold differences (593μg/m³ vs 3μg/m³) in peak PM2.5 between L1 and L2. Conclusions: Current OR ventilation monitoring standards demonstrate a fundamental measurement problem because the extreme PM exposures most likely to deliver infectious microbial inocula are highly localized and spatially heterogeneous, with substantially higher PM exposure detected at a field-proximal location. As a result, room-level standards risk normalizing metrics that are uncoupled from biologically relevant exposure. SSI prevention efforts should shift from costly architectural proxies (ventilation standards) to field-proximal PM monitoring that would support targeted smoke evacuation when exposure thresholds are exceeded.

Soft Tissue Remodeling in Infected Fields Using a Novel Extracellular Matrix: A Clinical Case Series Evaluation

Authors:
Cray Noah, Alexandra Smick, Meganoush Schmit, Frank Makhlouf, Latisha Stewart Smith, Isabel Lazo, Darin Saltzman

Body of Abstract:
Background:
Collagen-based extracellular matrices (ECMs) are widely used in regenerative medicine and have demonstrated benefit in complex wounds. Traditional ECMs, however, perform poorly in infected fields. This is especially true in cases of mesh infection and contaminated wounds, where microbial load inhibits healing. These scenarios carry high morbidity. Management of mesh infection often necessitates complete mesh explantation, a morbid and resource-intensive surgery. These challenges highlight the need for effective bioengineered solutions.

Multitissue platforms (MTPs) represent an emerging ECM technology designed to increase bioactive protein content relative to collagen alone, amplifying regenerative and immunomodulatory signaling. Xcellistem® Wound Powder, an MTP-based ECM developed by RTT Medical, provides a distinct advantage over conventional ECMs through its inherent antimicrobial activity. During degradation, Xcellistem releases matrix-specific peptides capable of directly killing bacteria, thereby reducing bioburden and enabling constructive remodeling even in culture-positive environments. This dual regenerative-and-antimicrobial mechanism positions Xcellistem as a uniquely suited solution for wounds involving infected mesh or complex contaminated wounds.

Methods:
We report a case series in five patients with complex contaminated wounds. Three patients presented with infected abdominal wall mesh, one had an enterocutaneous fistula, and one had a vulvar wound in previously irradiated tissue. Xcellistem was applied directly to the wound bed, with an overlying oil-emulsion sheet to serve as a non-adherent interface between dry dressings on top. The inner non-adherent layer was changed every 5-10 days, while the outer dry dressings were replaced every 24-48 hours. Wound appearance was sequentially monitored for healthy granulation tissue, epithelialization, and ultimate wound closure.

Results:
All three mesh-infection cases achieved complete healing without requiring mesh explantation surgery. The enterocutaneous fistula closed and its associated wound healed fully without operative intervention. The radiated vulvar wound demonstrated progressive granulation and ultimately healed completely. Across all cases, wound healing was steady and infection remained controlled. In contaminated or irradiated tissue, Xcellistem supported robust granulation and re-epithelialization.

Conclusions:
These early observations indicate that multitissue platform ECMs such as Xcellistem may offer a practical, non-surgical solution for wounds that traditionally fail to heal, including those in actively infected fields. By pairing regenerative bioactivity with inherent antimicrobial effects, Xcellistem demonstrated the ability to control infection and support durable tissue repair without operative intervention. This strategy may reduce mesh explantation rates and improve healing trajectories in high-risk and wounds. Larger, controlled trials are warranted.

Strepotococcus gallolyticus infections at a community hospital

Authors:
Saron Araya, Sridha Gona, Ifeanyi Chinedozi, Aaron George, Hugo Bonatti

Body of Abstract:
Background: Streptococcus gallolyticus – previously part of the Streptococcus bovis group – was identified and first described by Osawa et al. in 1995. While bacteremia and endocarditis remain the most frequent manifestations, Streptococcus gallolyticus may also cause other infections such as septic arthritis, osteomyelitis and intra-abdominal infections amongst others. Its presence in the microbiome has been linked to the development of colonic malignancies.

Methods: This is a retrospective analysis of all invasive infections involving Streptococcus gallolyticus between 9/2018 and 12/2022 at a rural hospital in the Appalachian region of the United States.  

Results: Twenty-seven isolates of Streptococcus gallolyticus in 13 patients were identified. Median age of the seven male and six female patients was 73.2 (range 52.2 – 91.1) years. Median BMI was 32 (range 21.1 – 52.3) kg/m2; 64% were obese. 62% of patients were diabetic, 62% had hyperlipidemia. 23% were active smokers and 8% had COPD; only 15% had malignancies. Bacteremia was the most common infection with 77%, two patients had lower extremity soft tissue infections and one had intraabdominal infection. 31% of infections were polymicrobial with Gram-negative rods accounting for 4 isolates (E. coli and Klebsiella spp 2 each) and anaerobes for 2 (Corynebacterium spp and Peptoniphilus asaccharolyticus). Demographic, clinical and microbiology data are shown in Table 1.

Conclusion: Streptococcus gallolyticus mainly causes bacteremia but may also cause intraabdominal and soft tissue infections. In contrast to other studies, our observed infections were not significantly associated with presence of colorectal cancer. On the other hand, strong association with obesity, metabolic syndrome and heart disease was found and patients were older than those presenting with infections with other streptococci.

Surgical Infections Curriculum Development Enhanced by Artificial Intelligence

Authors:
Kwame Wiafe, Anthony Dwyer, Neil Rubert, Laura Brown

Body of Abstract:
BACKGROUND

The explosion of medical knowledge makes it impossible to maintain current surgical infection education without new tools or approaches. Guidelines and reviews can lag behind recently published literature and require significant effort to produce. This study aims to explore whether Artificial Intelligence (AI) can be effectively used to improve the curation and development of an up-to-date, module-based curriculum, starting with a pilot topic focused on the prevention and treatment of superficial surgical site infections.

METHODS

Several Large Language Models (LLMs) were used to conduct targeted research on the treatment and prevention of superficial surgical infections. Each model was instructed to precisely identify high-quality, evidence-based articles, including randomized controlled trials, practice guidelines, systematic reviews, and primary research studies. The output from each model was compared to PubMed search results to generate articles that met quality standards (peer-review, availability, journal reputation) to reduce the likelihood of insufficient/incorrect data or AI-related hallucinations. The identified articles were uploaded into a specific LLM known for processing clinical evidence to establish a Retrieval-Augmented Generation (RAG) framework. Specific prompts and a content outline were used to minimize AI-related bias and misinterpretation. This RAG system was then used to produce the specialized content and code for a web-based application that hosts a structured, module-based curriculum. 

RESULTS

LLMs effectively synthesized the curated medical literature to develop a comprehensive, module-based curriculum. The final web application features six educational modules dedicated to the pilot topic on superficial surgical site infections (Figure 1). Each curriculum includes five AI-generated clinical case scenario questions amenable to psychometric data collection for content validation. The LLMs provided a ready-to-launch file that can be easily deployed on any network.

CONCLUSION

We have successfully demonstrated the feasibility of using AI to generate structured educational didactic materials based on current medical literature curated by the LLMs. Once openly reviewed by a community of experts, the resulting curriculum will provide surgeons with an easily accessible, evidence-based resource that can be quickly deployed on any network; thus, offering a scalable solution for keeping surgical education current.