Propensity Score-Weighted Analysis of Postoperative Infection in Patients With and Without Preoperative Urine Culture.

Importance: Although recent guidelines recommend against performance of preoperative urine culture before nongenitourinary surgery, many clinicians still order preoperative urine cultures and prescribe antibiotics for treatment of asymptomatic bacteriuria in an effort to reduce infection risk. Objective: To assess the association between preoperative urine culture testing and postoperative urinary tract infection (UTI) or surgical site infection (SSI), independent of baseline patient characteristics or type of surgery. Design, Setting, and Participants: This cohort study analyzed surgical procedures performed from January 1, 2017, to December 31, 2019, at any of 112 US Department of Veterans Affairs (VA) medical centers. The cohort comprised VA enrollees who underwent major elective noncardiac, nonurological operations. Machine learning and inverse probability of treatment weighting (IPTW) were used to balance the characteristics between those who did and did not undergo a urine culture. Data analyses were performed between January 2023 and January 2024. Exposures: Performance of urine culture within 30 days prior to surgery. Main Outcomes and Measures: The 2 main outcomes were UTI and SSI occurring within 30 days after surgery. Weighted logistic regression was used to estimate odds ratios (ORs) for postoperative infection based on treatment status. Results: A total of 250 389 VA enrollees who underwent 288 858 surgical procedures were included, with 88.9% (256 753) of surgical procedures received by males and 48.9% (141 340) received by patients 65 years or older. Baseline characteristics were well balanced among treatment groups after applying IPTW weights. Preoperative urine culture was performed for 10.5% of surgical procedures (30 384 of 288 858). The IPTW analysis found that preoperative urine culture was not associated with SSI (adjusted OR [AOR], 0.99; 95% CI, 0.90-1.10) or postoperative UTI (AOR, 1.18; 95% CI, 0.98-1.40). In analyses limited to orthopedic surgery and neurosurgery as a proxy for prosthetic implants, the adjusted risks for UTI and SSI were also not associated with preoperative urine culture performance. Conclusions and Relevance: This cohort study found no association between performance of a preoperative urine culture and lower risk of postoperative UTI or SSI. The results support the deimplementation of urine cultures and associated antibiotic treatment prior to surgery, even when using prosthetic implants.

EUS-guided management of anastomotic stricture: A case report.

INTRODUCTION AND IMPORTANCE: Anastomotic stenosis after low anterior resection is a serious complication and at times even requires surgical revision of the anastomosis. CASE PRESENTATION AND CLINICAL DISCUSSION: The patient presented with a 4.0 cm tubulovillous adenoma of the proximal rectum and underwent low anterior resection with loop ileostomy and subsequent reversal. The case was complicated by complete anastomotic stenosis. A novel technique was utilized to create an Endoscopic Ultrasound (EUS)-guided neo-anastomosis endoscopically. CONCLUSION: EUS-guided creation of a neo-colorectal anastomosis is a safe and effective alternative to surgical anastomosis revision of a completely stenosed anastomosis.

Estimated Risk of Adverse Surgical Outcomes Among Patients With Recent COVID-19 Infection Using Target Trial Emulation Methods.

This cohort study emulates a trial within a large national veteran population to assess the risk of adverse postoperative outcomes among patients with recent COVID-19 infection.

Events, care, and outcomes after hernia mesh explantation for infection.

BACKGROUND: Mesh explantation for infection after hernia surgery sets a cascade of events that has not been previously described. The purpose of this study is to review the care of these patients and outcomes. METHODS: We obtained data on all Veterans Health Administration enrollees undergoing hernia repair during 2008-2015. All mesh explantation cases were identified and manually reviewed through December 2020 to identify surgical site occurrences, re-repairs, and subsequent explantations. RESULTS: We identified 332 index explantations due to infection. A first subsequent repair was performed in 82.5% (274/332); a second repair in 18.2% (50/274); a third repair in 16.0% (8/50); and a fourth repair in 25% (2/8). Overall recurrence rate over a 12 year-period was 160/332 (48.1%). CONCLUSIONS: Mesh explantation due to infection sets a cascade of complications and hernia recurrences necessitating re-operation. Complications resulting from mesh explantation suggest that resolution of the initial abdominal wall infection is crucial to prevent future mesh infections.

Risk of Hernia Mesh Explantation following Early Versus Late Onset Skin and Soft Tissue Infection.

To estimate the relative risk of explantation in patients with skin and soft tissue infection onset within 90 days of hernia surgery, compared with days 91-365 and after 1 year. BACKGROUND: Infectious complications occurring after hernia repair with synthetic mesh require prolonged treatment, and eventual mesh explantation. Little is known whether early versus late onset infection is associated with differential risk of mesh removal, and whether treatment with long-term antibiotics or debridement are associated with mesh salvage. METHODS: This was a retrospective observational cohort study. We obtained data on all inguinal, umbilical, and ventral hernia repairs with implanted synthetic mesh performed in Veterans Affairs hospitals during 2008-2015. Participants without a 5-year infection after hernia surgery were excluded. Logistic regression estimated the association of mesh explantation with exposure to mesh-related infection during postoperative days 0-90, versus days 91-365 versus after 1 year. Additional covariates included any subsequent abdominal operation, antibiotic administration, and incision and drainage (I&D) or debridement procedures. RESULTS: One thousand eight hundred eighty-five patients underwent index hernia repair and developed a skin and soft tissue infection within 5 years. Infection onset during days 91-365 was associated with increased explantation risk (OR, 1.62; 95% CI, 1.04-2.48), as was increased antibiotic use (OR, 1.04; 95% CI, 1.03-1.05) and surgical treatments (OR, 3.74; 95% CI, 3.02-4.67). Subsequent abdominal operation was associated with lower explantation risk (OR, 0.46; 95% CI, 0.33-0.61). CONCLUSIONS: Early infections may be more suitable for conservative management. Later-onset infections have lower probability of mesh salvage and should be considered for earlier explantation to save the patients prolonged courses of antibiotics and surgical interventions.

Re-Infection after Explantation of Infected Hernia Mesh: Are the Same Micro-Organisms Involved?

Background: It is unclear if a history of mesh explantation for infection is predictive of future microbiology after subsequent hernia operations. We investigated how often the same causative organism is cultured in the initial explantation and subsequent repairs. Patients and Methods: We obtained data on patients undergoing ventral/incisional, umbilical, and inguinal hernia repairs from the Veterans Affairs Surgical Quality Improvement Program during 2008-2015. Manual review was performed for all patients with an administrative code indicative of mesh explantation and those with explantation for infection were retained. We then obtained data on cultured organisms from the mesh site at the time of index explantation and at any re-repair or subsequent explantation during a follow-up period ending in December 2020. Results: We identified 332 patients undergoing mesh explantation because of infection (64.8% ventral, 18.7% umbilical, 16.6% inguinal). Mean age was 60.3 years (standard deviation [SD], 9.7) and 93.9% were male. The same organism was cultured at re-infection in 23 of 59 (39%) cases. Gram-positive micro-organisms were the most prevalent in 20 of 23 (87%). Among the gram-positive, Staphylococcus aureus was the most common pathogen and was cultured in 18 of 20 (90%) cases, of which 14 of 18 (77.8%) were methicillin-susceptible Staphylococcus aureus (MSSA) and 4 of 18 (22.2%) were methicillin-resistant Staphylococcus aureus (MRSA). Three of 23 (13%) gram-negative organisms were the same at both re-infection and index explantation consisting of Escherichia coli in 2 of 3 (66.7%), and Pseudomonas aeruginosa in one of three (33.3%). Conclusions: Identification of organisms at time of prosthetic infection is helpful not only in treating the initial infection, but also in prevention of infection with the same organisms after subsequent repairs. Same organism re-infection should not be underestimated, particularly when Staphylococcus aureus is isolated.

Incidence and Risk Factors for Long-Term Mesh Explantation Due to Infection in More than 100,000 Hernia Operation Patients.

BACKGROUND: Infectious complications after hernia operation are potentially disastrous, often requiring long-term antibiotic administration, debridement, and mesh explantation. Our objective was to describe the long-term incidence and risk factors for synthetic mesh explantation due to infection after hernia operation in a large cohort. STUDY DESIGN: Retrospective database study using Veterans Affairs Surgical Quality Improvement Program and chart review of veterans undergoing abdominal or groin hernia repair with synthetic mesh implantation during 2008-2015. The main outcome was mesh explantation due to infection within 5 years. RESULTS: The study population consisted of 103,869 hernia operations, of which 74.3% were inguinal, 10.7% umbilical, and 15.0% ventral. Explantation incidence was highest among ventral (1.5%). Median explantation interval overall was 208 days. In multivariable logistic regression, all obesity levels from pre-obesity to obesity class III were associated with higher explantation risk. American Society of Anesthesiology physical status classification of 3 to 5 was associated with odds ratio (OR) of 1.7 (95% CI, 1.28 to 2.26), as was longer operative duration (OR 1.83; 95% CI, 1.51 to 2.21), and contaminated or dirty surgical wound classification (OR 2.27; 95% CI, 1.11 to 4.64). Umbilical repair (OR 6.11; 95% CI, 4.14 to 9.02) and ventral repair (OR 14.35; 95% CI, 10.39 to 19.82) were associated with higher risk compared with inguinal. Open repair was associated with a higher risk compared with laparoscopic (OR 3.57; 95% CI, 2.52 to 5.05). Deep incisional surgical site infection within 30 days of operation was more likely to result in long-term mesh explantation (29.2%) than either superficial (6.4%) or organ space infection (22.4%). CONCLUSIONS: Mesh explantation for infection is most common after ventral hernia repair. Risk factor optimization is crucial to minimize such an end point.

Interaction of Alpha-Crystallin with Phospholipid Membranes.

Purpose/Aim: The amount of membrane-bound α-crystallin increases significantly with age and cataract formation, accompanied by a corresponding decline in the level of α-crystallin in the lens cytoplasm. The purpose of this research is to evaluate the binding affinity of α-crystallin to the phospholipid membranes as well as the physical properties of the membranes after α-crystallin binding. Materials and Methods: The continuous wave and saturation recovery electron paramagnetic resonance (EPR) methods were used to obtain the information about the binding affinity and the physical properties of the membrane. In this approach, the cholesterol analog spin label CSL was incorporated in the membrane and the binding of α-crystallin to the membrane was monitored by this spin label. Small uni-lamellar vesicles were prepared from 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) with 1% of CSL. The measured membrane properties included the mobility parameter, fluidity, and the oxygen transport parameter. Results: The binding affinity (Ka ) of α-crystallin with the POPC membrane was estimated to be 4.9 ± 2.4 µM-1. The profiles of mobility parameter showed that mobility parameter decreased with an increase in the binding of α-crystallin. The profiles of spin-lattice relaxation rate showed that the spin-lattice relaxation rate decreased with an increase in binding. These results show that the binding of α-crystallin makes the membrane more immobilized near the head group region of the phospholipids. Furthermore, the profiles of the oxygen transport parameter indicated that the oxygen transport parameter decreased with an increase of binding, indicating the binding of α-crystallin forms a barrier for the passage of non-polar molecules which supports the barrier hypothesis. Conclusions: The binding of α-crystallin to the membrane alters the physical properties of the membranes, and this plays a significant role in modulating the integrity of the membranes. EPR techniques are useful in studying α-crystallin membrane interactions.

Neural Network Model to Detect Long-Term Skin and Soft Tissue Infection after Hernia Repair.

Background: Skin and soft tissue infection (SSTI) after hernia surgery is infrequent yet catastrophic and is associated with mesh infection, interventions, and hernia recurrence. Although hernia repair is one of the most common general surgery procedures, uncertainty persists regarding incidence of long-term infections. Our goal is to develop a machine learning regression model that detects the occurrence of long-term hernia-associated SSTI. Patients and Methods: The data set consisted of veterans receiving hernia repair with implanted synthetic mesh during 2008-2015. The outcome of interest was occurrence of SSTI related to the index hernia surgery over a five-year follow-up. A neural network regression was fit on a medical record reviewed sample, then applied to the study population. Results: The study population was 96,435 surgeries, of which 76,886 (79.7%) were inguinal, 11,177 (11.6%) were umbilical, and 8,372 (8.7%) were ventral. In the training set, 40 patients had SSTI probability ≥90%, of whom 38 (95%) had a true SSTI. In 249 patients with SSTI probability <10%, only five (2%) patients had a true SSTI. In the testing set, nine patients were assigned a probability >90% and all were true-positives. In 100 patients with probability <10%, only two (2%) patients had a true infection. C-statistics were 0.929 in the training set and 0.901 in the testing set. Conclusions: The model showed excellent discrimination between those with and without infection and had good calibration. The model could be used to reduce the cost of detecting long-term infections.

Comparing cataract surgery complication rates in veterans receiving VA and community care.

OBJECTIVES: To compare 90-day postoperative complication rates between Veterans receiving cataract surgery in VA vs Community Care (CC) during the first year of implementation of the Veterans Choice Act. DATA SOURCES: Fiscal Year (FY) 2015 VA and CC outpatient data from VA's Corporate Data Warehouse (CDW) 10/01/14-9/30/15). FY14 data were used to obtain baseline clinical information prior to surgery. STUDY DESIGN: Retrospective one-year study using secondary data to compare 90-day complication rates following cataract surgery (measured using National Quality Forum (NQF) criteria) in VA vs CC. NQF defines major complications from a specified list of Current Procedural Terminology (CPT) codes. We ran a series of logistic regression models to predict 90-day complication rates, adjusting for Veterans' sociodemographic characteristics, comorbidities, preoperative ocular conditions, eye risk group, and type of cataract surgery (classified as routine vs complex). DATA COLLECTION: We linked VA and CC users through patient identifiers obtained from the CDW files. Our sample included all enrolled Veterans who received outpatient cataract surgery either in the VA or through CC during FY15. Cataract surgeries were identified through CPT codes 66 984 (routine) and 66 982 (complex). PRINCIPAL FINDINGS: Of the 83,879 cataract surgeries performed in FY15, 31 percent occurred through CC. Undergoing complex surgery and having a high-risk eye (based on preoperative ocular conditions) were the strongest clinical predictors of 90-day postoperative complications. Overall, we found low complication rates, ranging from 1.1 percent in low-risk eyes to 3.6 percent in high-risk eyes. After adjustment for important confounders (eg, race, rurality, and preoperative ocular conditions), there were no statistically significant differences in 90-day complication rates between Veterans receiving cataract surgery in VA vs CC. CONCLUSIONS: As more Veterans seek care through CC, future studies should continue to monitor quality of care across the two care settings to help inform VA's "make vs buy decisions."

Association of Postoperative Infection With Risk of Long-term Infection and Mortality.

Importance: Surgical site infection has been shown to decrease survival in veterans by up to 42%. The association of 30-day postoperative infections with long-term infections in the overall surgical population remains unknown. Objective: To determine whether exposure to 30-day postoperative infection is associated with increased incidence of infection and mortality during postoperative days 31 to 365. Design, Setting, and Participants: In this retrospective observational cohort study, veterans undergoing major surgery through the Veterans Health Administration from January 2008 to December 2015 were included. Stabilized inverse probability of treatment weighting was used to balance baseline characteristics of the control and exposure groups. Cox proportional hazards regression was used to estimate hazard ratios of long-term infection and mortality. Data were analyzed from September 2018 to May 2019. Exposures: Any 30-day postoperative infection (exposure group) vs no 30-day infection (control group). Main Outcomes and Measures: Number of days between index surgery and the occurrence of death or the patient's first infection during postoperative days 31 to 365. Patients who died before having a long-term infection were censored for the infection outcome. Results: Of the 659 486 included patients, 604 534 (91.7%) were male, and the mean (SD) age was 59.7 (13.6) years. Among these patients, 23 815 (3.6%) had a 30-day infection, 43 796 (6.6%) had a long-term infection, and 24 810 (3.8%) died during follow-up. The most frequent 30-day infections were surgical site infection (9574 [40.2%]), urinary tract infection (6545 [27.5%]), pneumonia (3515 [14.8%]), and bloodstream infection (1906 [8.0%]). Long-term infection types included urinary tract infection (21 420 [48.7%]), skin and soft tissue infection (14 348 [32.6%]), bloodstream infection (3862 [8.8%]), and pneumonia (2543 [5.8%]). Patients in the exposure group had a higher observed incidence of long-term infection (5187 of 23 815 [21.8%]) and mortality (3067 of 23 815 [12.9%]) compared with those without 30-day infection (38 789 of 635 671 [6.1%] and 21 743 of 635 671 [3.4%], respectively). The estimated hazard ratio for long-term infection was 3.17 (95% CI, 3.05-3.28) and for mortality was 1.89 (95% CI, 1.79-1.99). Conclusions and Relevance: At any given point during the follow-up period, patients with 30-day postoperative infection had a 3.2-fold higher risk of 1-year infection and a 1.9-fold higher risk of mortality compared with those who had no 30-day infection. Cost-benefit calculations for surgical infection prevention programs should include the increased risk and costs of long-term infection and death. Preventive efforts in the first 30 days postoperatively may improve long-term patient outcomes.

Data on highway maintenance, rehabilitation, and mobility projects for integrated planning in Texas.

State Highway Agencies (SHAs) have different functional groups that work towards improving the functional and physical performance of highway assets. These functional groups often propose multiple inter-related highway projects on the same network. However, the respective information systems of such functional groups lack interoperability capabilities between them. This data article is related to an earlier study by France-Mensah et al. (France-Mensah et al., 2017) that explored the integrated visualization of highway projects proposed by different functional groups working in the same highway agency. This dataset provides a spatially integrated set of maintenance and capital planning projects which is rarely available due to organizational silos which often exist in highway agencies. The data includes approximately 700 highway projects with over 16 attributes that includes spatial, temporal, cost, and description attributes. The highway projects are located in the Fort Worth District of the Texas Department of Transportation (TxDOT) which is responsible for a large network (approximately 9000 lane miles) of highway assets. The agency currently oversees around $4 billion in construction projects and spends around $120 million annually for asset preservation. An analysis of the fund allocations categorized by different project types for pavement and bridge assets is presented. The data presented can be used to compare competing approaches or policies for cross-asset allocation, spatial-temporal projects coordination, and safety planning in the infrastructure management domain.

A Longitudinal Study of S. aureus Infection in a National Cohort of Surgical Patients.

BACKGROUND: Postoperative infections are a common and often preventable complication of surgery. S. aureus is a prevalent organism cultured in these infections and is associated with morbidity, mortality, and increased healthcare utilization. However, the long-term burden of S. aureus infection in surgical patients is not well studied. The purpose of this retrospective observational study is to assess the incidence, time trend, and burden of S. aureus infection up to 1 year after surgery. METHODS: We obtained manually-reviewed data from the VA Surgical Quality Improvement Program (VASQIP) to identify surgeries in all major specialties. These were combined with laboratory microbiology and pharmacy data to identify pneumonia and infections of the urinary tract, surgical site, and blood. RESULTS: In the study population of 559,550 patients, S. aureus incidence decreased each year, from 2.1% in 2008 to 1.1% in 2015. Among these, incidence of methicillin-resistant S. aureus (MRSA) infection decreased from 0.7% to 0.4%, and methicillin-susceptible S. aureus (MSSA) decreased from 1.4% to 0.7%. S. aureus infection was associated with increased length of stay, ED utilization, inpatient admissions, as well as a 4-fold increase in mortality. CONCLUSIONS: This is one of the largest studies describing the long-term incidence of S. aureus in the surgical population of a national integrated healthcare system. We conclude that the burden of S. aureus infection extends well beyond the conventional 30-day postoperative window, and late infection should be included in assessing the effects of interventions.

Detection of cholesterol bilayer domains in intact biological membranes: Methodology development and its application to studies of eye lens fiber cell plasma membranes.

Four purported lipid domains are expected in plasma membranes of the eye lens fiber cells. Three of these domains, namely, bulk, boundary, and trapped lipids, have been detected. The cholesterol bilayer domain (CBD), which has been detected in lens lipid membranes prepared from the total lipids extracted from fiber cell plasma membranes, has not yet been detected in intact fiber cell plasma membranes. Here, a saturation-recovery electron paramagnetic resonance spin-labeling method has been developed that allows identification of CBDs in intact fiber cell plasma membranes of eye lenses. This method is based on saturation-recovery signal measurements of the cholesterol-analog spin label located in the lipid bilayer portion of intact fiber cell membranes as a function of the partial pressure of molecular oxygen with which the samples are equilibrated. The capabilities and limitations of this method are illustrated for intact cortical and nuclear fiber cell plasma membranes from porcine eye lenses where CBDs were detected in porcine nuclear intact membranes for which CBDs were also detected in lens lipid membranes. CBDs were not detected in porcine cortical intact and lens lipid membranes. CBDs were detected in intact membranes isolated from both cortical and nuclear fiber cells of lenses obtained from human donors. The cholesterol content in fiber cell membranes of these donors was always high enough to induce the formation of CBDs in cortical as well as nuclear lens lipid membranes. The results obtained for intact membranes, when combined with those obtained for lens lipid membranes, advance our understanding of the role of high cholesterol content and CBDs in lens biology, aging, and/or cataract formation.

Differences in Risk Scores of Veterans Receiving Community Care Purchased by the Veterans Health Administration.

OBJECTIVE: To assess differences in risk (measured by expected costs associated with sociodemographic and clinical profiles) between Veterans receiving outpatient services through two community care (CC) programs: the Fee program ("Fee") and the Veterans Choice Program ("Choice"). DATA SOURCES/STUDY SETTING: Administrative data from VHA's Corporate Data Warehouse in fiscal years (FY) 2014-2015. STUDY DESIGN: We compared the clinical characteristics of Veterans across three groups (Fee only, Choice only, and Fee & Choice). We classified Veterans into risk groups based on Nosos risk scores and examined the relationship between type of outpatient utilization and risk within each CC group. We also examined changes in utilization of VHA and CC in FY14-FY15. We used chi-square tests, t tests, and ANOVAs to identify significant differences between CC groups. PRINCIPAL FINDINGS: Of the 1,400,977 Veterans using CC in FY15, 91.4 percent were Fee-only users, 4.4 percent Choice-only users, and 4.2 percent Fee & Choice users. Mean concurrent risk scores were higher for Fee only and Fee & Choice (1.9, SD = 2.7; 1.8, SD = 2.2) compared to Choice-only users (1.0, SD = 1.2) (p < .0001). Most CC users were "dual users" of both VHA and CC in FY14-FY15. CONCLUSIONS: As care transitions from VHA to CC, VHA should consider how best to coordinate care with community providers to reduce duplication of efforts, improve handoffs, and achieve the best outcomes for Veterans.

Factors Associated with Hospital Admission after Outpatient Surgery in the Veterans Health Administration.

OBJECTIVE: To examine factors associated with 0- to 7-day admission after outpatient surgery in high-volume specialties: general surgery, orthopedics, urology, ear/nose/throat, and podiatry. STUDY DESIGN: We calculated rates and assessed diagnosis codes for 0- to 7-day admission after outpatient surgery for Centers for Medicare and Medicaid Services (CMS) and Veterans Health Administration (VA) dually enrolled patients age 65 and older. We also estimated separate multilevel logistic regression models to compare patient, procedure, and facility characteristics associated with postoperative admission. DATA COLLECTION: 2011-2013 surgical encounter data from the VA Corporate Data Warehouse; geographic data from the Area Health Resources File; CMS enrollment and hospital admission data. PRINCIPAL FINDINGS: Among 63,585 outpatient surgeries in 124 facilities, 0- to 7-day admission rates ranged from 5 percent (podiatry) to 28 percent (urology); nearly 66 percent of the admissions occurred on the day of surgery. Only 97 admissions were detected in the CMS data (1 percent). Surgical complications were diagnosed in 4 percent of admissions. Procedure complexity, measured by relative value units or anesthesia risk score, was associated with admission across all specialties. CONCLUSION: As many as 20 percent of VA outpatient surgeries result in an admission. Complex procedures are more likely to be followed by admission, but more evidence is required to determine how many of these reflect potential safety or quality problems.