Introduction: The obesity pandemic presents numerous challenges in radiography, including patients exceeding the weight limits of imaging equipment, difficulties in palpating anatomical landmarks and inadequate penetration resulting in inaccurate diagnoses and need for repeat imaging resulting in increased radiation exposure. Pneumonia is a common reason for hospitalization, but identifying an infiltrate on the chest radiograph (CXR) in obese patients can be challenging. Conversely, motion artefacts may be misinterpreted as areas of pneumonia resulting in over-diagnosis and consequently the overuse of antibiotics. This study evaluated the diagnostic utility of CXR for identifying pneumonia in obese patients by comparing it with computed tomography (CT scan) performed within 72 hours. We also evaluated the impact on initiation or discontinuation of antibiotics – a very important aspect of antibiotic stewardship. Methods: All patients admitted between July 2020 and 2022 with a diagnosis of pneumonia who underwent both CXR and chest CT scan within a 72-hour window were included. Patients were divided into two groups obese and non-obese based on BMI. The results were evaluated to determine the concordance between the two modalities in diagnosing pneumonia, as well as its influence on antibiotic therapy. Results: A total of 320 patients were included, with a mean age of 65.3 years. 146 (45.6%) were male, and 174 (54.4%) were female. 202 (63.1%) were classified as obese (BMI > 30). CXR was performed as first modality in 313 (97.8%) cases, while 7 (2.2%) underwent CT scan first. In the obese group the overall concordance between the 2 modalities for diagnosing pneumonia was 67.5%. In the non-obese group the concordance was 80.2% (p < 0 .001). Among the obese patients who underwent CXR first, 11 (5%) had antibiotics discontinued after the CT scan results, while the number was 4 (3%) in the non-obese group. Additionally, 3 patients in the obese group had antibiotics initiated after the CT scan. Conclusions: Obesity poses unique challenges to healthcare facilities and imaging equipment. Diagnosing pneumonia in obese patients using CXR alone may result in over-diagnosis. This may lead to unnecessary antibiotic use and delayed diagnosis of alternate disease, or in some cases, missing a pneumonia and under-treatment. A chest CT scan is more sensitive and may be more helpful to identify a pneumonia accurately in these patients and thus facilitate appropriate antibiotic use.

Background and Objectives: Catheter associated urinary tract infections (CAUTIs) are a source of preventable harm in children. Insertion and maintenance bundles have significantly reduced CAUTIs, but infections still occur. Starting in mid-2019, we experienced an increase in CAUTIs in our pediatric intensive care unit (PICU). The objective was to identify preventable causes of CAUTI and develop and test interventions to reduce them. Methods: This quality improvement project was initiated in the PICU of a large tertiary children’s hospital. Interdisciplinary rounds led by the hospital epidemiologist and unit nursing leader with the bedside nurse occurred weekly (starting October 2019) for patients with urinary catheters in place for greater than three days. Discussions included strategies to optimize maintenance of the urinary catheter and identify catheters that could be removed. Additional interventions included no diapers for patients with a urinary catheter (starting March 2021) and use of a urine collection device that prevented both urine stasis in the drainage tube and retrograde flow of urine into the bladder (starting August 2021). Hand hygiene and CAUTI prevention bundle compliance was measured by direct observation of staff. CAUTIs were identified by prospective surveillance by infection prevention using standard definitions. The rate of CAUTIs over time was analyzed using statistical process control charts. Results: The baseline CAUTI rate (January 2017 - June 2019) was 0.5 infections/1000 catheter days with an average of 349 days between CAUTIs. Between July 2019 and February 2021, the CAUTI rate increased to 3.3 with an average of 88 days between CAUTIs. Annual compliance with hand hygiene and the CAUTI prevention bundle elements remained above 90% throughout all time periods. No improvement was seen after the institution of weekly interdisciplinary rounds. Starting in March 2021 after removal of diapers and implementation of the urine collection device that prevented retrograde flow, the CAUTI rate decreased to 0.9 and an average of 200 days between CAUTIs. Currently, it has been 512 days since the last CAUTI. Conclusion: CAUTIs decreased after removing diapers in children with urinary catheters and use of the urine collection device. Removal of diapers likely reduced stool contamination around the catheter and urethral opening. The urine collection device prevented inadvertent retrograde flow of urine into the bladder. These interventions could augment current CAUTI prevention strategies.

Background: Blood culture contamination is common in healthcare and contributes to diagnostic uncertainty, unnecessary treatments and follow-up testing, increased length of stay, higher rates of reportable healthcare-associated infections and events, over utilization of resources and staff including consultative care, and undue emotional stress to patients. The national benchmark for institutional blood culture contamination rates as recommended by The American Society for Microbiology (ASM) and the Clinical Laboratory Standards Institute (CLSI) is < 3 %. Our institution’s overall rate was 8.9% with the highest burden being from our Emergency Department (ED) locations. We formed a multidisciplinary team aimed to reduce these rates through efforts centered around education and simplification of the collection process. Method: Working closely with and gathering feedback from nursing staff, nurse educators, and supply chain, we developed a blood culture collection kit that included all items necessary for blood culture collection thus eliminating the need for nurses to gather these items individually prior to collection. Additionally, simple step-by-step educational materials (Fig. 1) detailing the collection technique were provided. Education was presented at nursing huddles and skills fairs prior to kit roll-out. Blood culture kits were then stocked in place of individual blood culture collection bottles in all ED stock rooms in August 2022. Result: The 12-week pre-intervention period found 249 contamination events from 4265 total collections deriving a contamination rate of 5.8% across our health system’s four ED locations. During a 12-week post-intervention period following kit roll-out, 116 contamination events occurred from 3629 total collections deriving a contamination rate of 3.2% across our four ED locations. Given our results, we ultimately rolled this out to all units in all locations of our health system. When including all time from kit rollout to present (August 2022 to November 2023, 16 months), there were 1077 contamination events from 43379 total collections deriving an overall contamination rate of 2.5%. When compared to the 16 months prior to the kit rollout (April 2021 to July 2022) there were 1803 contamination events in 49335 total collections (3.7% contamination rate) deriving an overall percent reduction of 32.1%. Conclusion: We were able to decrease our health system’s blood culture contamination rate through simple interventions aimed at reducing the mental burden on nursing staff by developing a blood culture collection kit and educational materials. Since implementation of the kits, we have continued to maintain lower contamination rates as evident by our 16 month follow up period.

Background: Central line-associated bloodstream infections (CLABSI) and catheter-associated urinary tract infections (CAUTI) are key healthcare-associated infection (HAI) quality metrics. In this qualitative analysis, we aimed to identify common issues contributing to CLABSIs and CAUTIs occurring during the COVID-19 pandemic. Methods: In an academic healthcare network in Atlanta, GA, four hospitals perform real-time, apparent cause analyses (ACAs) for all CLABSIs and CAUTIs. Contributing factors are entered as free text into an electronic database. We analyzed data from 8/2020–8/2022. We first performed a qualitative open card sort of all reported contributing factors to CLABSI and created a novel framework based on mutually defined critical tasks (e.g., line insertion) and cross-cutting issues (e.g., communication breakdown). Contributing factors could describe ≥1 critical task and/or ≥1 cross-cutting issue. After establishing interrater reliability, a multidisciplinary group applied this framework to classify each contributing factor. For CAUTI, we used the same set of cross-cutting issues but identified new critical tasks via open card sorting. We then used the framework to classify each CAUTI contributing factor. We used descriptive statistics to identify frequent critical tasks and cross-cutting issues. Results: We reviewed 350 CLABSI ACAs with 602 contributing factors and 240 CAUTI ACAs with 405 contributing factors (Figure 1). Our classification framework comprised 11 cross-cutting issues and 9 critical tasks for CLABSI and 7 critical tasks for CAUTI (Figure 2). CLABSI: The critical tasks most often reported were bathing (19%), central line dressing maintenance (15%), and assessing central line indication (8%; Figure 3). Within these tasks, the most frequent issues described for bathing were the task not being performed (20%) and unclear documentation (18%); for dressing maintenance, the task was not performed (15%), not documented (15%), or poorly performed due to lack of competency (15%); and for assessing line indication, there was frequent communication breakdown (33%). CAUTI: The critical tasks most often reported were urinary catheter care (26%) and assessing the indication for urinary catheter (22%; Figure 4). Within these tasks, urinary catheter care was frequently not documented (38%) or not performed (16%); assessing urinary catheter necessity was often not documented (29%) or involved breakdown of communication (19%). Conclusion: We created a novel framework to evaluate common causes of HAIs in an academic healthcare network. This framework can be used to identify and track gaps over time and to develop quality improvement initiatives targeting key tasks and associated factors, such as communication difficulties when assessing device indications.

Disclosure: Colleen Kraft: Consultant - REbiotix/Ferring; Scientific Advisory Board - Seres, LLC

Background: Contact precautions (CP) to prevent transmission of multidrug-resistant gram-negative (MDRGN) Enterobacteriaceae are recommended, although studies of discontinuation of CP (DcCP) have found no change in healthcare associated infections (HAI) due to extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae. Limited data exists on DcCP for MDRGN in a large health system. Methods: We performed a retrospective observational study analyzing the relationship between use of CP and HAI due to two definitions of MDRGN Enterobacteriaceae: ESBL, and non-susceptibility to ≥3 drug classes (3DC-GNR), with carbapenem resistant Enterobacteriaceae (CRE) serving as control. The study included all inpatient admissions from 2/2017 through 9/2022 at 21 acute care hospitals. Hospitals had latitude to determine CP practices based on local risk assessment, but in 2/2018, system-wide transmission-based precautions guidance was updated to recommend DcCP for MDRGN Enterobacteriaceae and in 12/2019 was updated to clarify DcCP specifically for ESBL and 3DC-GNR while continuing CP for carbapenem-resistant organism carriage. We interviewed infection preventionists to define when CP were used for CRE, ESBL, and 3DC-GNR Enterobacteriaceae. HAI were defined using National Healthcare Safety Network criteria including all HAI categories. We compared the incidence rate of HAI attributable to the two MDRGN types in hospital months with and without use of CP, with HAI due to CRE as a comparison group since all hospitals used CP for CRE throughout the study period. Results: The periods of CP use, by hospital, are shown in Figure 1. Throughout the study period, there were 987 HAI attributed to ESBL Enterobacteriaceae, 579 due to 3DC-GNR Enterobacteriaceae, and 329 due to CRE. Figure 2 shows the unadjusted aggregate rate of HAI for each of the three MRGN types, including among hospitals with and without CP in each month, for ESBL and 3DC-GNR. In months with and without CP, the rate of HAI was 1.482/10,000 and 1.093/10,000 patient days (incidence rate ratio [IRR], 1.356 [95% confidence interval, 1.195-1.540]) for ESBL Enterobacteriaceae. In months with and without CP, the rate of HAI was 1.071/10,000 and 0.493/10,000 patient days (IRR,2.173[95% confidence interval, 1.838-2.569]) for 3DC-GNR Enterobacteriaceae. Conclusion: DcCP was not associated with an increase in HAI due to ESBL and 3DC-GNR Enterobacteriaceae in aggregated facilities that self-selected for DcCP. Facilities that used CP were associated with significantly higher rates of ESBL and 3DC-GNR Enterobacteriaceae, a relationship that did not change as hospitals DcCP for these MDRGN. Further analyses are necessary to assess for a causal relationship.

Background: Patients in the intensive care unit (ICU) have invasive lines increasing their risk for healthcare-associated infections (HAIs). Our objective was to determine if antimicrobial bathing with 2% chlorhexidine gluconate (CHG) compared to the colloidal silver-based antimicrobial product would reduce the incidents of central line–associated bloodstream infections (CLABSI) and catheter-associated urinary tract infections (CAUTI). Methods: We performed a before-and-after study in four adult ICUs at a two-hospital facility in California. Prospective surveillance of CLABSI and CAUTI prevention bundles monitoring was established. The intervention consisted of daily bathing with CHG for all patients in the ICUs. A baseline period of one year was followed by an intervention period of one year. The incidence rates of CLABSIs and CAUTIs were compared between the baseline and intervention periods utilizing a t-test analysis. Results: A total of 10103 patients were included. At Facility A, a mean CLABSI rate of 2.43/1000 central line catheter days (CL) with 2149 patients days (Mean differences 95% CI -0.5–3.1; P>0.0975), during the baseline period followed by 1.11/1000 CL days with 2193 patient days in the intervention period. At Facility B, the mean CLABSI rate of 1.82/1000 CL days with 2976 patient days (Mean differences 95% CI -0.6–2.31; P>0.161) during the baseline period was followed by 1.01/1000 CL days with 2785 patient days in the intervention period. At Facility A, the mean CAUTI rate of 1.37/1000 indwelling catheter days (IUC) with 2149 ICU patient days (Mean difference 95% CI is 0.28–1.97; P 0.2160) was noted in the baseline period, followed by 0.45/1000 IUC days with 2785 in the intervention period. Conclusion: Daily bathing with CHG significantly reduced the incidence of CAUTI at Facility A. It is unclear why Facility A saw a statistically significant reduction in CAUTI, but Facility B did not. The difference in outcomes may be related to hospital size, service lines, supply constraints, and discrepancies in staffing. CHG bathing was not directly associated with a reduced risk of CLABSI at Facility A and B during our limited study, but it was encouraging enough that our organization will continue this intervention to obtain additional data to determine if bathing with CHG will reduce CLABSI and CAUTI.

Background: This study investigated viral load in surgical masks worn by adult patients infected with respiratory viruses. Method: Surgical masks were dissected into eight pieces at pre-selected sites: inner, middle, and outer layers at the nose (N1-N3) and mouth (M1-M3), as well as full-thickness on the right (RS) and left (LS) sides. Viral load was detected, correlated with nasopharyngeal specimens and patients' demographics. Result: Among 230 patients infected with influenza A virus (n=91), respiratory syncytial virus (RSV) (n=61), and SARS-CoV-2 (n=78) from April 1 to August 31, 2023, 90.9% (209/230) were from the medical specialty. Of the 230 surgical masks collected, viral RNA was detected in 79.6% at one or more sites, with 75.7% positive at N1 or M1, 55.2% positive at N3 or M3, and 22.6% exhibiting viral RNA at all sites. Pearson correlation showed viral load correlation between nasopharyngeal specimens and N1 (0.244, p=0.002) and M1 (0.174, p=0.031). The mean viral load at N1 (4.14 ± 1.46 log10 copies/ml) was significantly higher than M1 (3.74 ± 1.32 log10 copies/ml, p=0.014) and N3 (3.58 ± 1.27 log10 copies/ml, p=0.003). Significant differences in viral load were observed across N1-N3 and M1-M3 in RSV patients, but not in influenza A or SARS-CoV-2 patients. SARS-CoV-2 patients exhibited significantly lower viral load at RS and LS sites compared to influenza A or RSV patients. Conclusion: Viral RNA was detected in N3 or M3 sites in our masks, highlighting the potential risk associated in these areas. Differential viral load across various sites in surgical masks worn by patients infected with different respiratory viruses warrants further investigation.

Background: The impact of universal masking on transmission of endemic respiratory viruses in children’s hospitals is unknown. Our objective was to measure the association between universal masking by healthcare personnel and the incidence of non-SARS-CoV-2 healthcare-associated viral respiratory infections (HA-VRIs) in a free-standing academic pediatric medical center during the COVID-19 pandemic. Methods: In this quasi-experimental study, we measured the incidence rate of non-SARS-CoV-2 HA-VRIs (VRI diagnosed on or after hospital day 3 by one of several molecular assays) during three time periods: prior to the COVID-19 pandemic (pre-intervention: September 2013 - February 2020); during universal masking (intervention: May 2021 - March 2023); and after universal masking was lifted (post-intervention: April 2023 - November 2023). Although universal masking was implemented in late March 2020, we exclude the lockdown period of strict COVID-19-related public health mitigations (i.e., school closures and shelter-in-place advisories) during which community prevalence of non-SARS-CoV-2 respiratory viruses was minimal in our region (March 2020 to April 2021). By negative binomial regression analysis, we compared the level and trend of HA-VRIs between the pre-intervention and intervention periods. Results: Figure 1 illustrates the incidence rate of non-SARS-CoV-2 HA-VRI during the pre-intervention, lockdown, intervention, and post-intervention periods. The aggregate non-SARS-CoV-2 HA-VRI incidence rate during the pre-intervention, intervention, and post-intervention periods was 1.25, 1.84, and 1.96 HA-VRIs per 1000 patient days, respectively. There was no significant difference in the level (p = 0.96) or trend (p = 0.67) of HA-VRI incidence rate between the pre-intervention and intervention periods. Conclusion: Universal masking was not associated with a decrease in the incidence rate of non-SARS-CoV-2 HA-VRIs at our children’s hospital during the COVID-19 pandemic. These findings suggest that universal masking may not be an effective infection prevention measure in children’s hospitals during periods of increased endemic respiratory viral transmission in the community.

Disclosure: Larry Kociolek: Research Support - Merck

Background: Antimicrobial resistance is a growing public health threat. To alleviate selective pressure which leads to the emergence and proliferation of resistance, and to preserve the utility of treatments where they are needed the most, antimicrobial stewardship programs (ASPs) could consider revising surgical antibacterial prophylaxis protocols for low-risk procedures such as laparoscopic cholecystectomy. Methods: Publicly available data was used from a well-powered randomized controlled trial conducted by Matsui and colleagues during 2007-2013 in Japan on the effectiveness of prophylactic antibacterial treatment on reducing post-operative infections following laparoscopic cholecystectomy in low-risk patients. A total of 1037 patients were randomized to receive treatment or no treatment. After randomization, laparoscopic cholecystectomies were converted to open procedures in 28 patients, 14 in each arm, constituting a deviation from the protocol and the administration of additional antibacterial treatment. The original study included both intention-to-treat and per-protocol analyses, finding statistically significant reductions in post-operative infections in the treatment vs no treatment arm (1.2% vs 6.7%, p<0.0001; 1.0% vs 5.9%, p<0.0001, respectively). In the present analysis I assessed the extent to which type of procedure modified the effect of antibacterial prophylaxis on post-operative infection using both additive and multiplicative interaction. Risk and risk differences were estimated using a linear-binomial model and risk ratios were estimated using a log-binomial model. Alpha was set to 0.10. The lowest risk categories for each variable, being assigned to treatment and receiving a laparoscopic procedure, defined the common reference category. Results: A 35 percentage point (pp) increase in the risk of post-op infections relative to the reference category was attributable to the joint effects of omitting prophylaxis and conversion to an open procedure (90% CI 14, 56), compared to a 5 pp increase attributable to omission of prophylaxis (90% CI 3, 7) or a 6 pp increase attributable to conversion to an open procedure (90% CI -5, 18) by themselves. The interaction contrast capturedthis super-additive 24 pp increase in risk (90% CI -1, 47). The relative excess risk due to interaction was 23.81 (90% CI -5.56, 53.19), suggesting a departure from additivity as well. Conclusions: Patients undergoing open cholecystectomies stand to benefit the most from antibacterial prophylaxis compared to patients who have laparoscopic cholecystectomies. ASPs could consider reducing or eliminating surgical prophylaxis in low-risk procedures such as laparoscopic cholecystectomy to alleviate selection pressure for antibacterial resistant organisms and preserve its effectiveness for people undergoing higher risk procedures.

Although the National Healthcare Safety Network (NHSN) recommends the reporting of superficial incisional SSIs, the standardized infection ratio (SIR) models used by the NSHN exclude superficial incisional SSIs cases. Yet, some superficial incisional SSIs may lead to serious adverse patient outcomes. We previously proposed a new category of such infections: serious superficial incisional surgical site infections (SSISSIs), defined as a superficial incisional SSI that (1) required debridement in an operating room and/or (2) led to a hospital readmission within 30 days of surgery. The objective of our study was to determine the prevalence of SSISSIs in a large network of community hospitals and compare hospital rankings of SSI rates of organ/space and deep SSIs (complex SSIs) with and without SSISSIs. We performed a retrospective descriptive analysis of prospectively collected data on 35 NHSN surgical categories in 47 community hospitals within the Duke Infection Control Outreach Network (DICON) from 1/1/2013-12/31/2022. All hospitals used standardized surveillance and data collection strategies throughout the study period. The Wilcoxon rank-sum was used to test for differences in performance rankings of hospitals sorted by rates of complex SSIs alone compared to complex and SSISSI rates. A two-tailed P value of .05 or less was considered significant. Overall, 11,617 SSIs occurred after 1,272,257 surgeries (0.91 SSIs/100 procedures). Out of 3,996 superficial SSIs, 2,038 (17.5% overall, 51.0% of superficial incisional) met criteria for SSISSI. 112 (5.5%) were diagnosed during the current admission and required takeback to the OR for infection; 1,926 (94.5%) were diagnosed during a readmission; and 3841 (33.1%) were diagnosed during readmission and returned to the OR. (Table1) The highest proportion of SSISSIs was diagnosed in patients who underwent gastrointestinal surgery (32.0%) or orthopedic surgery (24.0%). (Table2) Performance ranking of individual hospitals based on rates of complex SSIs, differed significantly when including SSISSIs (p= 0.02). (Table3) Discussion Our findings suggest that SSISSIs make up a moderate but important proportion of SSIs in community hospitals. SSISSIs can be identified through established database surveillance looking at objective measures of returning to the OR for debridement and/or readmission within 30 days. Hospital rankings differed significantly when SSISSIs were added to complex SSIs to calculate SSI rates. As such, including SSISSIs likely provides a more accurate depiction of SSIs with important outcomes and is not as subjective to surveillance bias. Next steps would be specifically to look at outcomes data for complex SSIs compared to SSISSIs to fully evaluate the

Disclosure: Jessica Seidelman: UptoDate- Section Editor; BoneSupport- Consultant

Background: Immediate use steam sterilization (IUSS) shortens the time from sterilization to the aseptic transfer onto the surgical sterile field. Published data incompletely defines the extent to which IUSS increases risk of surgical site infection (SSI), compared to standard sterile reprocessing methods. We aimed to measure the association between IUSS use for surgical instrument reprocessing and SSI risk in a facility where IUSS use increased due to staffing constraints and case volumes. Methods: In this retrospective observational study at a tertiary care hospital with a diverse mix of surgery types, we used sterile reprocessing logs and SSI outcomes defined using National Health and Safety Network definitions to compare SSI rates among surgeries using surgical devices sterilized using IUSS compared to standard terminal sterilization methods. We calculated a risk ratio (RR) and 95% confidence interval (95%CI), including stratification by eleven high-volume service lines. Results: Among 23,919 surgical procedures, 416 (1.74%) developed SSIs. IUSS was used to sterilize instruments prior to 1,524 (6.37%) surgical procedures, and of these procedures 39 (2.56%) developed an SSI, compared to 1.68% of non-IUSS procedures (377 SSI in 22,395 procedures; risk ratio [RR] 1.52, 95% confidence interval [95%CI] 1.10-2.11). Two surgical services had statistically significant RRs for SSI development after IUSS: transplant surgery (RR 2.47, 95%CI 1.32-4.60] and plastic surgery (RR 3.64, 95%CI 1.13-11.74; Figure). Conclusion: IUSS is associated with a significant increase in SSIs, including among varied surgery types. IUSS utilization should be minimized.

Background: Use of a combination of parenteral and oral antimicrobial prophylaxis prior to colorectal surgery is recommended to reduce risk of surgical site infection (SSI). Parenteral antibiotic selection is complicated by the need to target organisms likely to cause infection at the surgery site, while mitigating risk of antimicrobial resistance caused by overuse of broad spectrum agents. This study aimed to evaluate microbiologic data from colorectal surgical site infections across an 11-hospital health system. Microbiologic data from SSI events were used to assess continued appropriateness of health system standard recommendations for parenteral antibiotic prophylaxis in colorectal surgery, consisting of either cefazolin with metronidazole or cefoxitin monotherapy. Methods: This multicenter, retrospective, observational study was conducted from January 1, 2019 to March 31, 2023, using data extracted from the National Healthcare Safety Network (NHSN). Microbiologic data from colorectal SSIs from 2019 to 2022 were evaluated for a descriptive review of pathogen and phenotype trends. SSI data excluded patients age < 18 years, those identified as infection present at time of surgery (PATOS), or outpatient procedures. Results: A total of 8059 colorectal procedures were evaluated. Most SSIs were polymicrobial, with at least one pathogen detected in 65% of cases. The most commonly identified organisms were E. coli (22.5%), Enterococcus spp. (19.7%), P. aeruginosa (6.5%), Streptococcus spp. (4.9%), and C. albicans (4.7%). Change over time in antimicrobial-resistant phenotypes from 2019 to 2022 was not statistically significant for extended-spectrum cephalosporin-resistant E. coli (p=0.335), extended-spectrum cephalosporin-resistant K. oxytoca/pneumoniae (p=0.189), multi-drug resistant P. aeruginosa (0.058), methicillin-resistant S. aureus (p=0.906), or among isolates with no identified antimicrobial-resistance phenotype (p=0.096). Among E. coli, change from 2019 to 2022 in cefazolin non-susceptible, ceftriaxone susceptible isolates was not statistically significant (p=0.177). No carbapenem-resistant Enterobacterales isolates were identified among non-PATOS cases. Conclusions: Data does not support a change to broader spectrum agents for colorectal surgery parenteral antimicrobial prophylaxis. Continued use of cefazolin with metronidazole or cefoxitin as IV antibiotic prophylaxis in colorectal surgery is recommended, with ongoing tracking of microbiologic trends and antimicrobial susceptibility.

Background: Guidelines recommend bundles with multiple infection control elements to prevent surgical site infections (SSI). Although effective in multiple research studies, little is known about the implementation of such complex bundles in the real-world clinical setting. Methods: A survey was distributed to the SHEA Research Network (SRN) hospitals during November 2022 – December 2023, to assess processes related to the implementation of SSI prevention bundles in colorectal surgery. Results: Of the 93 US and international hospitals within SRN, 49 completed the survey (53% response rate). The mean volume of colorectal surgeries per year was 377 (median 400). Figure 1 shows the individual elements of SSI prevention bundle reported as consistently used in most surgeries. There were no significant differences between hospitals with high vs. low volume (cut-off 400 surgeries), except for wound protectors or retractors, more likely to be used in high-volume hospitals (P = 0.047). A formal process for auditing adherence was reported by 71% of respondents for antibiotic prophylaxis, and 51% for skin prep, with the remaining elements audited < 50% of the time. Feedback of audited adherence to surgeons occurred < 50% of the time for all bundle elements, except antibiotic prophylaxis (59%). Table 1 shows the most common barriers reported as either successfully mitigated or still persistent at the time of the survey. High-volume hospitals were more likely to report persistent clinicians’ low bundle adherence (P = 0.016) and inadequate bundle adherence audit and feedback (P = 0.0016). Conclusion: Implementation of guideline-recommended colorectal SSI Prevention bundles remains highly variable. Further research aiming to develop strategies that optimize implementation and adherence is needed.

Background: Administration of antimicrobial prophylaxis close to incision time is recommended as an essential practice to prevent surgical site infections (SSI). Despite guideline recommendations, adherence to preoperative intravenous antibiotic guidelines is variable. We aim to assess perioperative factors associated with guideline concordant (GC), guideline second line (GSL) and non-guideline concordant (NGC) antibiotic choice and timing and impact on odds of SSI. Methods: 3173 patients at 9 hospitals with National Health Safety Network (NHSN) procedure codes for colon surgery and abdominal hysterectomy between January 1, 2023, and October 31, 2023, were identified from the electronic medical record. Data on preoperative intravenous antibiotic choice and timing, history of allergy and methicillin resistant staphylococcus aureus (MRSA) history was collated. SSI were identified using NHSN definitions by trained infection preventionists. SSI identified as present at the time of surgery were excluded. Antibiotic choice and timing were compared to institutional guidelines and patients were categorized as having received GC, GSL or NGC antibiotic choice, and GC or NGC antibiotic timing. Descriptive statistics were used to describe clinical data for patient population and subgroups who received GC, GSL and NGC antibiotics. Univariate logistic regression was performed to assess the association of procedural and clinical factors with the likelihood of an SSI. Results: GC was high overall for both antibiotic choice (94%) and timing (94%). (Table 1) NGC and GSL antibiotic choice were more common in colon surgery, urgent/emergent cases, patients with beta lactam allergies and those with a recent history of MRSA. GSL antibiotic choice was more frequent in inpatients. (Table 2). GC antibiotic timing was more common with GC antibiotic choice (98%) than with NGC (37%) or GSL (51$) antibiotic choice. Odds of SSI were lower in patients who were GC for both antibiotic choice and timing (OR 0.4, p < 0 .001) and increased in patients who received GSL antibiotic choice (OR 5.7 compared to GC, p < 0 .001), underwent urgent/emergent surgeries (OR 4.6, p < 0 .001) or had a history of MRSA in the past year (OR 8.4, p < 0 .001). We found a non-significant trend toward lower infections in patients with GC antibiotic timing (OR 0.5, p 0.08). (Table 3) Conclusion: Combined GC for antibiotic choice and timing was high and associated with lower odds of SSI. NGC and GSL antibiotic choice were associated with patient level factors such as history of MRSA and emergent procedures which may also impact risk of SSI.

Background: Frequent use of delayed sternal closure and prolonged stays in critical care units contribute to surgical site infections among pediatric patients undergoing cardiothoracic (CT) procedures. Bundled interventions to prevent or reduce surgical site infections (SSIs) have shown prior success, but limited data exist on sustainability of these efforts especially during the Coronavirus Disease 2019 (COVID-19) pandemic. Here, we re-examine the SSI rates for pediatric CT procedures after the onset of the pandemic. Methods: In a single academic center providing regional quaternary care, we created a multidisciplinary CT-surgery SSI Prevention workgroup in response to rising CT SSI rates. Bundle elements focused on daily chlorhexidine bathing, environmental cleaning, monthly room changes, linen management, antimicrobial prophylaxis, and sterile techniques for beside and operating room procedures. CDC surveillance definitions were used to identify superficial, deep or organ space SSIs. To assess the bundle’s sustainability, we compared SSI rates during years impacted by the COVID-19 pandemic (2021–2023, period 2) to pre-pandemic rates (2017–2019, period 1). Data from 2020 were excluded to account for bundle implementation, pandemic restrictions, and a minor decrease in surgical volumes. Rates were calculated as surgical site infection cases per 100 procedures. Mean rates across both periods were compared using paired t-tests (Stata/SE version 14.2). Results: Excluding the year 2020, the average SSI rate per 100 CT procedures increased from 1.07 in period 1 to 1.56 in period 2(p=0.55). Concurrently, the average SSI rate per 100 CT procedures with delayed closures increased from 1.49 in period 1 to 1.97 in period 2(p=0.67). Figure 1 shows SSI rates and procedure counts for 2017–2023. Coagulase negative Staphylococci most frequently caused SSIs in period 1 while methicillin-susceptible Staphylococcus aureus (MSSA) was most frequently identified in period 2. During period 2, the estimated compliance with SSI prevention bundle remained stable and reached 95% for pre-operative chlorhexidine baths and use of appropriate antimicrobial prophylaxis. Monthly room changes with dedicated environmental cleaning reached 100% compliance. Conclusion: Despite staffing shortages and resource limitations (e.g., discontinuation of contact isolation for MRSA colonization) during the COVID-19 pandemic, SSI rates for pediatric CT surgeries showed a slight, but non-statistically significant, increase in post-pandemic years as compared to pre-pandemic years. implementation of bundled interventions and improved surveillance methods may have sustainably impacted these SSI rates. Reinforcing bundle adherence as well as identifying additional prevention interventions to incorporate in pre-, intra-, and post-operative periods may improve patient outcomes.

Background: Traditional manual surveillance of healthcare-associated infections often neglects certain hospital areas. This study investigated the potential of automated hospital-onset bacteremia (HOB) detection to enhance surveillance comprehensiveness. Our focus was on assessing baseline HOB levels across a large university hospital and demonstrating the algorithm’s ability to discern infection patterns in different hospital areas. Method: Conducted at one of the three sites of Charité university hospital in Berlin, Germany, our study employed an automated HOB detection algorithm, collaboratively developed with the PRAISE (Providing a Roadmap for Automated Infection Surveillance in Europe) network. HOB was defined as a positive blood culture (BC) with a recognized pathogen or two positive BC with common commensals, occurring two days post-admission or later. A retrospective data analysis spanned 2018-2022, with data extraction in January 2024. HOB rates were calculated per 1,000 patient-days and correlated with BC sampling frequency. Trends over time were examined. A comparison was made between intensive care units (ICU) and non-ICU. Result: Data from 58 wards (10 ICU, 48 non-ICU) with 262,058 in-patient admissions and 1,634,793 patient-days were included. Baseline characteristics of the hospital site are summarized in Table 1. Aggregated HOB rates over a 5-year period (Table 2) were substantially higher in ICU compared to non-ICU, applicable to all HOB, HOB with common commensals, and HOB with pathogens. A scatterplot (Figure 1) illustrates a strong correlation between BC sampling frequency and HOB rates in ICU, while Figure 2 displays HOB rates and BC sampling frequency in ICU over time. Notably, HOB rates were higher in the years 2020 and 2021, followed by a decrease in 2022, despite a continually high BC sampling rate. Discussion: The algorithm consistently detected HOB, providing insights into distinctions between ICU and non-ICU. While fewer HOB occurred in non-ICU, continuous monitoring remains crucial, given that the total number of HOB in non-ICU was higher than in ICU, and HOB in non-ICU might currently be overlooked by established surveillance activities. The automated system also demonstrated its effectiveness in identifying trends over time. Although speculative, it appears likely that the higher HOB rates in 2020 and 2021 were at least partially attributable to the COVID-19 pandemic and accompanying factors. There was a notable correlation between HOB and BC sampling frequency. However, the fact that HOB incidence in ICU decreased in 2022 despite persistently high BC sampling frequency rates, indicates the influence of other factors on HOB rates.

Background: Candida auris infection is associated with high morbidity and mortality. C. auris can persist in the healthcare environment and is associated with outbreaks. We compare screening strategies for C. auris in two high-risk patient populations. Methods: Our center is a tertiary, 865-bed hospital. In the context of known regional outbreaks of C. auris in post-acute care (PAC) facilities, we experienced extended clusters of apparent C. auris acquisition across several hospital units. Hospital acquisition was defined as new C. auris in clinical cultures in patients with no known history of C. auris colonization/infection. We performed point prevalence surveys (PPS) on affected units weekly until all tests were negative for two consecutive weeks. We also initiated admission screening for C. auris for patients admitted from PAC. All screening swabs were collected per CDC’s procedure. Tests were performed either by RT-PCR or Chromagar C. auris media, depending on availability. We compared the overall positivity rates of exposure PPS versus PAC admission screenings using Z-test for two proportions with statistical significance set at p < 0 .05 Results: From 2/2023-12/2023, a total of 533 tests on 367 unique patients were processed during PPS; 512 tests were negative and 21 were positive (3.9% positivity rate). Three additional samples were either unable to be processed or indeterminate. There were 68 patients who had repeat testing weekly for ≥2 weeks. Most remained negative, but 5 tested positive after variable amounts of negative-week intervals: 3 patients at week 2, 1 patient at week 4 and 1 patient at week 5. From 8/2023 to 12/2023, a total of 89 patients admitted from 35 different PAC facilities underwent admission screening for C. auris. Only three patients were positive (3.4%), each from a different facility. The difference in the positivity rates between PPS and PAC was not statistically significant (Z-score 0.25, p = 0.79). Discussion: Our C. auris screening strategies found similar positivity rates for patients admitted to the hospital from PACs compared to targeted PPS in the setting of apparent hospital acquisition events. These strategies may be considered as complementary. Facilities experiencing apparent acquisition events should consider screening high-risk admissions to identify and isolate colonized patients, particularly if standard infection prevention practices are being performed with high fidelity.

Epidemiology of carbapenem-resistant organisms (CRO) has focused on transmission in acute care hospital or long-term care facility (LTCF) settings. Few investigations have examined community-associated (CA)-CRO, with no consensus about common exposures. To explore possible exposures, the New York City (NYC) Department of Health and Mental Hygiene investigated suspected CA-CRO cases through routine surveillance among NYC residents with specimens collected during December 2020-May 2023. CA-CRO cases were defined as urine or skin specimens with bacterial cultures exhibiting carbapenem resistance, among individuals aged ≤70 years with no international travel, hospitalization, or LTCF stays within 12 months before specimen collection. Inclusion was determined by reviewing data from health information exchanges, when available electronic medical records, and telephone screening for those not excluded through record review. We identified 426 suspected cases for review, those not meeting the case definition were excluded; 44 individuals were not reached for screening. A preliminary questionnaire was fielded with 12 individuals and then refined to capture additional potential exposures. Analyses were completed with 23 individuals interviewed with the refined questionnaire. Of the 23, 70% were female; 39% were Hispanic, 17% Black, and 17% White; their median age was 60 years (range: 26-70 years). Further, 83% reported an outpatient appointment, 48% reported an outpatient procedure/surgery, and 9% reported having a hospitalized household member, all within 12 months before specimen collection; 26% had a urinary catheter or indwelling device within 2 days of specimen collection. Additionally, 30% reported taking antibiotics within 3 months of specimen collection, 52% denied taking antibiotics, 9% were unsure about antibiotic use, and 9% did not answer the question. Whole genome sequencing (WGS) was performed on 14 available isolates from CA-CRO cases by the NYC Public Health Laboratory or Wadsworth Center (WC), of which only 7 could be compared with isolates previously sequenced at WC (2017-2023). Six isolates were separated by >50 mutation events, suggesting no close genomic relationship. One isolate from 2021 was 11 mutation events from a 2018 isolate from the same individual, consistent with the expected evolutionary rate. While infrequent, CA-CRO cases occur in NYC. Outpatient healthcare, antibiotic use, and urinary catheters or indwelling devices were common self-reported exposures. Analyses were limited by screening non-response. Increased specimen availability for WGS could enhance investigation of CA-CRO exposure patterns. Health information exchange data were often incomplete and future surveillance could benefit from healthcare and public health partnerships and better documentation for more complete electronic medical histories.

Background: Infection preventionists (Ips) have self-reported surveillance as the most time-consuming job task (1,2). APIC’s MegaSurvey 2020 reported that 60% of Ips consider themselves proficient or expert within this competency domain (2). Accurate coding of health care acquired infections is critical to identifying epidemiologically significant events, using data to improve practice, and compliance with state and federal mandated CMS reporting (3,4). Validated case study scenarios were distributed to infection preventionists to better understand how experience level and time spent performing surveillance affects interrater reliability (IRR) in applying the National Healthcare Safety Network (NHSN) surveillance definitions (5,6). Methods: Case study scenarios determined to have high item discrimination were added to an online test bank and distributed annually to Ips of varying experience levels and care settings as part of a mandatory training program (5). The test bank currently consists of forty-two validated questions. Each year, the participants receive approximately thirty questions, including twenty randomly selected from the test bank and ten beta scenarios under development. Only validated test bank scenarios are used to calculate the passing score of 85%. Participants are blinded to which questions are test bank scenarios versus beta scenarios. Additional information was gathered at the beginning of the test to determine CIC status, years of experience, and weekly hours spent doing surveillance. Data was analyzed for passing score on the first attempt for testing years 2019, 2021, 2022, and 2023. Results: Thirty-six Ips passed the IRR test on the first attempt (33%). Of those who passed on the first attempt, twenty-nine (81%) were certified and twenty-two (61%) reported at least nine hours a week performing surveillance. Of the seventy-three Ips (67%) who did not pass on the first attempt, thirty were certified (41%) and sixty (82%) reported performing surveillance for 8 hours or less per week. Conclusion: The first-time pass rate for certified and non-certified Ips was 33%, markedly lower than the self-reported proficiency rate of 60%. The majority of Ips who passed on the first attempt were certified and spent at least nine hours per week performing surveillance. certified and non-certified Ips who did not regularly perform surveillance as part of their weekly job tasks were less likely to pass the test on the first attempt. Given the first-time pass rate among all participants is below optimal, establishing inter-rater reliability systems and ongoing surveillance education for Ips is crucial to ensure accuracy of publicly reported data.