Sampling for the diagnosis of orthopaedic surgical infections.

Orthopaedic surgical infections, in Denmark, are managed heterogeneously, both within the orthopaedic surgical and the clinical microbiological specialty. More uniform guidelines for sampling and clinical microbiological diagnostics for suspected orthopedic surgical infections would be appropriate. The purpose of this review is therefore to initiate a process aiming for consensus on sampling methods of tissue materials and fluids and clinical microbiological sample handling.

Impact of systematic diabetes screening on peri-operative infections in patients undergoing cardiac surgery.

Detection of high glycated hemoglobin (A1c) is associated with worse postoperative outcomes, including predisposition to develop systemic and local infectious events. Diabetes and infectious Outcomes in Cardiac Surgery (DOCS) study is a retrospective case-control study aimed to assess in DM and non-DM cardiac surgery patients if a new screening and management model, consisting of systematic A1c evaluation followed by a specialized DM consult, could reduce perioperative infections and 30-days mortality. Effective July 2021, all patients admitted to the cardiac surgery of IRCCS ISMETT were tested for A1c. According to the new protocol, glucose values of patients with A1c ≥ 6% or with known diabetes were monitored. The diabetes team was activated to manage therapy daily until discharge or provide indications for the diagnostic-therapeutic process. Propensity score was used to match 573 patients managed according to the new protocol (the Screen+ Group) to 573 patients admitted before July 2021 and subjected to the traditional management (Screen-). Perioperative prevalence of infections from any cause, including surgical wound infections (SWI), was significantly lower in the Screen+ as compared with the Screen- matched patients (66 [11%] vs. 103 [18%] p = 0.003). No significant difference was observed in 30-day mortality. A1c analysis identified undiagnosed DM in 12% of patients without known metabolic conditions. In a population of patients undergoing cardiac surgery, systematic A1c evaluation at admission followed by specialist DM management reduces perioperative infectious complications, including SWI. Furthermore, A1c screening for patients undergoing cardiac surgery unmasks unknown DM and enhances risk stratification.

Logistic regression model predicts early surgical site infection after spinal fusion: a retrospective cohort study.

OBJECTIVE: This study aimed to develop a diagnostic model for predicting early surgical site infection (SSI) based on postoperative inflammatory markers after spinal fusion surgery. METHODS: In this retrospective study, we analysed the trends of inflammatory markers between SSI and non-SSI groups. The data were randomly divided into training cohort and validation cohort (ratio 7:3). The variables for SSI were analysed using stepwise logistic regression to develop the prediction model. To evaluate the model, we analysed its sensitivity, specificity, positive predictive value, negative predictive value, as well as the area under the curve in the validation cohort. Calibration plots and decision curve analysis were employed to assess the calibration and clinical usefulness of the model. FINDINGS: We observed significant changes in inflammatory markers on the seventh day after surgery. The prediction model included four variables on the seventh day after surgery: body temperature, C-reactive protein, erythrocyte sedimentation rate and neutrophil counts. After binary processing of these data, the simplified model achieved an area under the curve of 0.86 (95% confidence interval (CI): 0.81-0.92) in the training cohort and 0.9 (95% CI: 0.82-0.98) in the validation cohort. Calibration plots and decision curve analysis demonstrated that the proposed model was effective for the diagnosis of SSI. CONCLUSION: We developed and validated a prediction model for diagnosing early infection after spinal fusion.

Accuracy of the Wound Healing Questionnaire in the diagnosis of surgical-site infection after abdominal surgery in low- and middle-income countries.

INTRODUCTION: Telemedicine is being adopted for postoperative surveillance but requires evaluation for efficacy. This study tested a telephone Wound Healing Questionnaire (WHQ) to diagnose surgical site infection (SSI) after abdominal surgery in low- and middle-income countries. METHOD: A multi-centre, international, prospective study was embedded in the FALCON trial; a factorial RCT testing measures to reduce SSI in seven low- and middle-income countries (NCT03700749). It was conducted according to a pre-registered protocol (SWAT126) and reported according to STARD guidelines. The reference test was in-person review by a trained clinician at 30 postoperative days according to US Centres for Disease Control criteria. The index test was telephone administration of an adapted WHQ at 27 to 30 postoperative days by a researcher blinded to the outcome of in-person review. The sum of item response scores generated an overall score between 0 and 29. The primary outcome was the diagnostic accuracy of the WHQ, defined as the proportion of SSI correctly identified by the telephone WHQ, and summarized using the area under the receiving operator characteristic curve (AUROC) and diagnostic test accuracy statistics. RESULTS: Patients were included from three upper-middle income (396 patients, 13 hospitals), three lower-middle income (746 patients, 19 hospitals), and one low-income country (54 patients, 4 hospitals). 90.3% (1088 of 1196) patients were successfully contacted. Those with non-midline incisions (adjusted odds ratio: 0.36, 95% c.i. 0.17 to 0.73, P=0.005) or a confirmed diagnosis of SSI on in-person assessment (odds ratio: 0.42, 95% c.i. 0.20 to 0.92, P=0.006) were harder to reach. The questionnaire correctly discriminated between most patients with and without SSI (AUROC 0.869, 95% c.i. 0.824 to 0.914), which was consistent across subgroups. A representative cut-off score of ≥4 displayed a sensitivity of 0.701 (0.610-0.792), specificity of 0.911 (0.878-0.943), positive predictive value of 0.723 (0.633-0.814) and negative predictive value of 0.901 (0.867-0.935). CONCLUSION: SSI can be diagnosed using a telephone questionnaire (obviating in-person assessment) in low resource settings.

A wound infection happens when germs enter the cut made in your body by a doctor when you are operated on. Germs are small organisms that cannot be seen by your eyes, but they can cause problems in the healing of the cut. Infection is the most common problem after surgery and can delay you getting out of hospital and back to normal life. The current way to check whether you have an infection is for a doctor or nurse to look at the cut made on your tummy and see how it is healing. For example, a doctor may check if the cut has a green liquid oozing from it or if the area of the wound is red or swollen. A month after you leave hospital, a doctor may ask you to come back for a follow-up visit. However, this will require you to travel to hospital and take a day off work or away from your family, and can be expensive and time-consuming if you travel far. We wanted to find out if talking to a doctor over the phone would work as well as you travelling to hospital to show the wound to a doctor or nurse in person. To do this, we asked over 1000 patients who had recently undergone surgery to be checked using both methods­to take a phone call from one doctor and be checked in person by a different doctor. We were able to compare the phone follow-up and in-person check to see if the doctors came to a different conclusion. We also looked at whether patients were able to receive a phone call at home and their experience of the process. For most patients, the phone call from a doctor was just as good at seeing if a patient had an infection as a face-to-face check-up by a doctor. However, the phone call was not perfect all the time, particularly for patients with very mild infections. Most patients were able to receive the phone call after a few tries and all patients were very happy with the process. As an international research team, we are now trying new ways to improve the phone call, including looking at the wound over video if possible. A phone call to check how your wound is healing can now be used as a substitute for a face-to-face check-up by a doctor. If you have any worries about your wound after the phone call you should still seek help from a doctor or nurse. We hope that the phone call will be more convenient for patients like you to avoid travelling back to hospital and taking time away from your work and family.

-A machine learning model to predict surgical site infection after surgery of lower extremity fractures.

PURPOSE: This study aimed to develop machine learning algorithms for identifying predictive factors associated with the risk of postoperative surgical site infection in patients with lower extremity fractures. METHODS: A machine learning analysis was conducted on a dataset comprising 1,579 patients who underwent surgical fixation for lower extremity fractures to create a predictive model for risk stratification of postoperative surgical site infection. We evaluated different clinical and demographic variables to train four machine learning models (neural networks, boosted generalised linear model, naïve bayes, and penalised discriminant analysis). Performance was measured by the area under the curve score, Youdon's index and Brier score. A multivariate adaptive regression splines (MARS) was used to optimise predictor selection. RESULTS: The final model consisted of five predictors. (1) Operating room time, (2) ankle region, (3) open injury, (4) body mass index, and (5) age. The best-performing machine learning algorithm demonstrated a promising predictive performance, with an area under the ROC curve, Youdon's index, and Brier score of 77.8%, 62.5%, and 5.1%-5.6%, respectively. CONCLUSION: The proposed predictive model not only assists surgeons in determining high-risk factors for surgical site infections but also empowers patients to closely monitor these factors and take proactive measures to prevent complications. Furthermore, by considering the identified predictors, this model can serve as a reference for implementing preventive measures and reducing postoperative complications, ultimately enhancing patient outcomes. However, further investigations involving larger datasets and external validations are required to confirm the reliability and applicability of our model.

Nocardia keratitis after small incision lenticule extraction (SMILE).

We report the case of a female patient in her late 20s who visited the clinic with concerns about poor vision, redness, watering and a burning sensation in her left eye 2 weeks after undergoing a small incision lenticule extraction. She had no history of systemic illness or immunosuppressed status. On slit lamp examination, she was found to have corneal stromal infiltrates in the interface at multiple locations. Given the clinical diagnosis of microbial keratitis, corneal scraping of the interface infiltrate was performed and sent for microbiological examination revealing gram-positive, thin, beaded filaments that were acid-fast positive and later identified by growth in culture media as Nocardia species. This case was managed successfully with the use of topical amikacin and systemic trimethoprim-sulfamethoxazole with complete resolution of infection.

Is there a role of calprotectin testing in the diagnosis of surgical site infections after total hip and knee arthroplasty? A preliminary study.

BACKGROUND: Recent studies have revealed the usefulness of synovial calprotectin (CLP) in diagnosing chronic periprosthetic joint infections (PJIs). However, there is still a lack of evidence to support the use of serum CLP in the diagnosis of early PJIs and surgical site infections (SSIs) after total joint arthroplasties (TJAs). OBJECTIVES: The primary aim of this study is to investigate the standard kinetics of CLP concentrations in the blood during the very early postoperative period after non-complicated total hip arthroplasty (THA) and total knee arthroplasty (TKA). The secondary aim was to perform a preliminary comparison of CLP concentrations between non-infected patients and patients with recognized SSIs. MATERIAL AND METHODS: A total of 64 consecutive patients who underwent primary THA and TKA were included in this prospective research. Sixty patients (30 THA and 30 TKA) were scheduled to determine the standard shape of the blood CLP curve and the expected concentrations during the first 5 postoperative days after non-complicated TJAs. In 4 additonal patients, early SSI was confirmed, and they were included in a separate SSI subgroup. RESULTS: Calprotectin demonstrated a linear increase during the first 5 postoperative days. Statistically significant differences in CLP concentrations between non-infected cases and SSIs were not observed. The preoperative median results with interquartile range (Q1-Q3) were 0.52 (0.39-0.64) mg/dL and 0.5 (0.47-0.52) mg/dL (p = 0.77), while post operation they were as follows: on postoperative day 1: 0.88 (0.53-1.3) mg/dL and 0.86 (0.62-1.1) mg/dL (p = 0.84), on postoperative day 3: 1.77 (1.29-2.08) mg/dL and 1.85 (1.70-1.95) mg/dL (p = 0.72), and on postoperative day 5: 2.32 (1.79-2.67) mg/dL and 2.56 (2.25-2.83) mg/dL (p = 0.55), respectively. CONCLUSION: Serial CLP measurements during the early postoperative period revealed a linear (statistically significant) increase in concentration to postoperative day 5 without an evident point of decrease. A significant difference in median values and the course of curve patterns between the non-complicated and SSI groups was not observed.

Quality check: concordance between two monitoring systems for postoperative organ/space-surgical site infections in rectal cancer surgery. Linkage of data from the Catalan Cancer Plan and the VINCat infection surveillance programme.

BACKGROUND: The Catalan Cancer Plan (CCP) undertakes periodic audits of cancer treatment outcomes, including organ/space surgical site infections (O/S-SSI) rates, while the Catalan Healthcare-associated Infections Surveillance Programme (VINCat) carries out standardized prospective surveillance of surgical site infections (SSI) in colorectal surgery. This cohort study aimed to assess the concordance between these two monitoring systems for O/S-SSI following primary rectal cancer surgery. METHODS: The study compared O/S-SSI incidence data from CCP clinical audits versus the VINCat Programme in patients undergoing surgery for primary rectal cancer, in 2011-12 and 2015-16, in publicly funded centres in Spain. The main outcome variable was the incidence of O/S-SSI in the first 30 days after surgery. Concordance between the two registers was analysed using Cohen's kappa. Discordant cases were reviewed by an expert, and the main reasons for discrepancies evaluated. RESULTS: Pooling data from both databases generated a sample of 2867 patients. Of these, O/S-SSI was detected in 414 patients-235 were common to both registry systems, with satisfactory concordance (κ = 0.69, 95% confidence interval 0.65-0.73). The rate of discordance from the CCP (positive cases in VINCat and negative in CCP) was 2.7%, and from VINCat (positive in CCP and negative in VINCat) was 3.6%. External review confirmed O/S-SSI in 66.2% of the cases in the CCP registry and 52.9% in VINCat. CONCLUSIONS: This type of synergy shows the potential of pooling data from two different information sources with a satisfactory level of agreement as a means to improving O/S-SSI detection. CLINICALTRIALS: gov Identifier: NCT06104579. Registered 30 November 2023.

An explainable long short-term memory network for surgical site infection identification.

BACKGROUND: Currently, surgical site infection surveillance relies on labor-intensive manual chart review. Recently suggested solutions involve machine learning to identify surgical site infections directly from the medical record. Deep learning is a form of machine learning that has historically performed better than traditional methods while being harder to interpret. We propose a deep learning model, a long short-term memory network, for the identification of surgical site infection from the medical record with an attention layer for explainability. METHODS: We retrieved structured data and clinical notes from the University of Utah Health System's electronic health care record for operative events randomly selected for manual chart review from January 2016 to June 2021. Surgical site infection occurring within 30 days of surgery was determined according to the National Surgical Quality Improvement Program definition. We trained the long short-term memory model along with traditional machine learning models for comparison. We calculated several performance metrics from a holdout test set and performed additional analyses to understand the performance of the long short-term memory, including an explainability analysis. RESULTS: Surgical site infection was present in 4.7% of the total 9,185 operative events. The area under the receiver operating characteristic curve and sensitivity of the long short-term memory was higher (area under the receiver operating characteristic curve: 0.954, sensitivity: 0.920) compared to the top traditional model (area under the receiver operating characteristic curve: 0.937, sensitivity: 0.736). The top 5 features of the long short-term memory included 2 procedure codes and 3 laboratory values. CONCLUSION: Surgical site infection surveillance is vital for the reduction of surgical site infection rates. Our explainable long short-term memory achieved a comparable area under the receiver operating characteristic curve and greater sensitivity when compared to traditional machine learning methods. With explainable deep learning, automated surgical site infection surveillance could replace burdensome manual chart review processes.

A rare case of postoperative Metamycoplasma hominis surgical site infection in a patient after bilateral lung transplantation.

Following the COVID-19 infection, the sternum dislocation and wound dehiscence resulted in an infection complicating the recovery of an immunosuppressed patient after bilateral lung transplantation. Anaerobic culture (96 h) of milky cloudy wound secretion resulted in the growth of pinpoint haemolytic colonies identified as Metamycoplasma hominis (formerly Mycoplasma hominis). The search for the endogenous source of the infection found the bacterium exclusively in the patient's sputum, making a possible link to donor lung M. hominis colonization. Unfortunately, the donor samples were no longer available. The wound infection was successfully treated with 17 days of clindamycin despite the continuous PCR detection of M. hominis in the sputum after the end of the treatment.

A woman in her fifties with a post-operative infection, generalised rash and organ failure. / En kvinne i 50-årene med postoperativ infeksjon, generalisert utslett og organsvikt.

Background: Toxic shock syndrome (TSS) is a rare but potentially life-threatening disease caused by superantigen-producing Gram-positive bacteria such as Staphylococcus aureus and Streptococcus pyogenes. Staphylococcal TSS received special attention from 1978 to 1981, when an epidemic was observed associated with the use of hyper-absorbent tampons. Today the disease is rare and generally not related to menstruation, but can occur postpartum or in post-surgical wounds, intrauterine devices (IUDs), burns or other soft tissue injuries, mastitis or other focal infections. The annual incidence of staphylococcal TSS is around 0.5/100 000 and around 0.4/100 000 for streptococcal TSS. The mortality in menstrual-related cases is < 5 % and up to 22 % in non-menstrual related cases. Case presentation: This article presents a case of a middle-aged woman who developed symptoms of toxic shock syndrome five days after elective breast cancer surgery, with high fever, multiorgan failure and a characteristic desquamation of the palms. Interpretation: Toxic shock syndrome is a potentially lethal, toxin-mediated disease. Symptoms develop quickly, within hours. Early recognition and appropriate surgical management, intensive care and antibiotics are therefore important to reduce mortality and sequelae.

Recurrent sternal wound infection caused by Gordonia bronchialis after open heart surgery.

Gordonia bronchialis is an aerobic gram-positive bacilli and also weakly acid fast. It requires a long incubation time and extensive biochemical reactions for identification. Therefore, use of broad-range polymerase chain reaction (PCR) for amplification of genes such as 16S rRNA or hsp65 followed by sequencing or advanced techniques like MALDI-TOF MS is needed for identification. Here, we present a case of persistent sternal wound infection following open heart surgery, caused by G. bronchialis in a 58 years old male, identified using MALDI-TOF MS-based system. The patient improved with oral Cefpodoxime 200 mg BD for four weeks.

Nomogram for predicting surgical site infections in elderly patients after open lumbar spine surgery: A retrospective study.

The aim of this study is to develop a nomogram to assess the risk of surgical site infection in elderly patients undergoing open lumbar spine surgery and explore related risk factors. We reviewed the records of 578 elderly patients who had undergone open lumbar spine surgery. The clinical parameters were subjected to lasso regression and logistic regression analyses. Subsequently, a nomogram was constructed to predict the risk of postoperative surgical site infection and validated using bootstrap resampling. A total of 578 patients were included in the analysis, of which 17 were diagnosed as postoperative surgical site infection. Following the final logistic regression analysis, obesity, hypoalbuminemia and drinking history were identified as independent risk factors and subsequently incorporated into the nomogram. The nomogram demonstrated excellent discrimination, with an area under the receiver-operating characteristic curve of 0.879 (95% CI 0.769 ~ 0.989) after internal validation. The calibration curve exhibited a high level of consistency. Decision curve analysis revealed that this nomogram had greater clinical value when the risk threshold for surgical site infection occurrence was >1% and <89%. We had developed a nomogram for predicting the risk of postoperative surgical site infection in elderly patients who had undergone open lumbar spine surgery. Validation using bootstrap resampling demonstrated excellent discrimination and calibration, indicating that the nomogram may hold potential clinical utility as a simple predictive tool for healthcare professionals.

Incidence and healing times of postoperative sternal wound infections: a retrospective observational single-centre study.

Objectives: Analyses of incidence and time required to heal sternal wound infections after heart surgery performed via a median sternotomy between 2020 and 2022. Results: Superficial wound infections (SWI) were five times more common (2.7%) than mediastinitis (0.5%) among 2693 patients. The median time between the operation and diagnosis of SWI was 26 (interquartile range [IQR] 15-33) days vs. 16 (IQR 9-25) days for mediastinitis (p = .12). Gram-negative bacteria caused 44% of the 85 infections. Sternal wound infection correlated to higher body mass index, female sex, smoking, diabetes mellitus, previous myocardial infarction, coronary artery bypass grafting, use of internal mammary graft, and re-entry for postoperative bleeding. Eight of 59 patients (13.6%) with sternal wound infections had bilateral mammary grafts, compared to 102 of 1191 patients (8.6%) without wound infections (p = .28). Negative pressure wound therapy was always used to treat mediastinitis and applied in 63% of patients with SWI. Two of 13 patients with mediastinitis (15%) and none of 72 patients with SWI died within 90 days after the operation. The median time until the wound healed was 1.9 (IQR 1.3-3.7) months after SWI vs. 1.7 (IQR 1.3-5.3) months after mediastinitis (p = .63). Six patients (7%) required longer than one year to treat the infection. Conclusions: Postoperative sternal wound infections usually appeared several weeks after surgery and were associated with factors as high body mass index, diabetes mellitus and coronary artery bypass. SWI were more common than mediastinitis and often required negative pressure wound therapy and similar treatment time as mediastinitis.

Effectiveness of HealthTracker for post-caesarean section surgical site infection surveillance: An intervention study.

This intervention study aimed to implement and evaluate the effectiveness of HealthTracker, a post-discharge surgical site infection surveillance system. Participants were 730 women birthing by caesarean section at a large hospital over a 6-month period. Data were downloaded from clinical data systems and HealthTracker. Receiver operating characteristics were used to assess HealthTracker. Over a 6-month period, 382 women completed HealthTracker, with 83 scoring ≥6, indicating signs and symptoms of surgical site infection. Of this 83, 58 sought advice from health professionals, 29 returned to hospital, and 45 received antibiotics. A total of 20 infections from a total population of 730 were confirmed, with 14 out of 382 respondents confirmed via HealthTracker. Receiver operating characteristics identified HealthTracker as an excellent indicator of surgical site infection. HealthTracker is a feasible mHealth option for monitoring post-discharge surgical site infection post-caesarean section. In addition, by providing alerts, advising women to monitor their symptoms and seek treatment if necessary, HealthTracker has the potential to enhance self-efficacy for surgical wound monitoring at home.

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.

[Pay attention to the prevention and treatment of deep sternal wound infection after sternotomy].

Deep sternal wound infection (DSWI) is one of the potential and catastrophic complications after cardiac surgery. Despite the use of smaller incisions, routine application of prophylactic antibiotic and optimized blood glucose management, the incidence rate of DSWI still fluctuates between 1% and 5%. The early symptoms and signs of DSWI are not often obvious, making it too late for the clinicians to intervene in the process. Once left untreated, DSWI carries a very high mortality rate. Therefore, early prevention, diagnosis, and appropriate management of DSWI are crucial in preventing its progression to life-threatening outcomes. Considering the clinical severity and treatment complexity of DSWI, this article focuses on preventive experiences in each stage of DSWI, and reconstructive strategies after DSWI happens, raising attention among the medical community regarding DSWI.

Predictive value of C-reactive protein for postoperative liver-specific surgical site infections.

BACKGROUND: C-reactive protein is a useful biological tool to predict infectious complications, but its predictive value in detecting organ-specific surgical site infection after liver resection has never been studied. We aimed to evaluate the predictive value of c-reactive protein and determine the cut-off values to detect postoperative liver resection-surgical site infection. METHODS: A multicentric analysis of consecutive patients with liver resection between 2018 and 2021 was performed. The predictive value of postoperative day 1, postoperative day 3, and postoperative day 5 C-reactive protein levels was evaluated using the area under the receiver operating characteristic curve. Cut-off values were determined using the Youden index in a 500-fold bootstrap resampling of 500 patients treated at 3 centers, who comprised the development cohort and were tested in an external independent validation cohort of 166 patients at a fourth center. RESULTS: Among the 500 patients who underwent liver resection of the development cohort, liver resection-surgical site infection occurred in 66 patients (13.2%), and the median time to diagnosis was 6.0 days (interquartile range, 4.0-9.0) days. Median C-reactive protein levels were significantly higher on postoperative day 1, postoperative day 3, and postoperative day 5 in the liver resection-surgical site infection group compared with the non-surgical site infection group (50.5 vs 34.5 ng/mL, 148.0 vs 72.5 ng/mL, and 128.4 vs 35.2 ng/mL, respectively; P < .001). Postoperative day 3 and postoperative day 5 C-reactive protein-level area under the curve values were 0.76 (95% confidence interval, 0.64-0.88, P < .001) and 0.82 (95% confidence interval, 0.72-0.92, P < .001), respectively. Postoperative day 3 and postoperative day 5 optimal cut-off values of 100 mg/L and 87.0 mg/L could be used to rule out liver resection-surgical site infection, with a negative predictive value of 87.0% (interquartile range, 70.2-93.8) and 76.0% (interquartile range, 65.0-88.0), respectively, in the validation cohort. CONCLUSION: Postoperative day 3 and postoperative day 5 C-reactive protein levels may be valuable predictive tools for liver resection-surgical site infection and aid in hospital discharge decision-making in the absence of other liver-related complications.

Effectiveness of Closed Incision Negative Pressure Wound Therapy for Infrainguinal Bypass in the Vascular Quality Initiative.

BACKGROUND: To analyze surgical site infections (SSIs) after infrainguinal bypass for standard dressings versus closed incision negative pressure wound therapy (ciNPWT) in the Society for Vascular Surgery's Vascular Quality Initiative (VQI). METHODS: We retrospectively analyzed SSI after infrainguinal bypass procedures in the VQI from December 2019 to December 2021 comparing ciNPWT and standard dressings. The primary outcome of any superficial or deep wound infection at 30 days was analyzed in a subset of procedures with 30-day follow-up data (cohort A, n = 1,575). Secondary outcomes including in-hospital SSI, return to the operating room (OR) for infection, and length of stay (LOS) were analyzed for all procedures (cohort B, n = 9,288). Outcomes were analyzed in propensity-matched cohorts. RESULTS: Patients who received ciNPWT (n = 1,389) were more likely to be female (34% vs. 32%, P = 0.04) with a higher rate of smoking history (90% vs. 86%, P = 0.003), diabetes (54% vs. 50%, P = 0.007), obesity (34% vs. 26%, P < 0.001), prior peripheral vascular intervention (57% vs. 51%, P < 0.001), and to prosthetic conduit (55% vs. 48%, P < 0.001) compared to patients with standard dressings (n = 7,899). After propensity matching of cohort A (n = 1,256), the 30-day SSI rate was 4% (12/341) in the ciNPWT and 6% (54/896) in the standard dressing group (P = 0.07, 95% CI 0.03-1.06). In the propensity-matched in-hospital cohort B (n = 5,435), SSI was 3% (35/1,371) in the ciNPWT group and 2% (95/4,064) in the standard dressing group (P = 0.66). There was no difference in the rate of return to the OR for infection, 1% (36/4,064) vs. 1% (19/1,371) (P = 0.13) or LOS, 9.0 vs. 9.0 days (P = 0.86) for the standard versus ciNPWT groups. CONCLUSIONS: In this analysis of the VQI registry, the use of ciNPWT after infrainguinal bypass did not result in a statistically significant decrease in 30-day SSI. We recommend that surgeons consider the use of ciNPWT as part of a bundled process of care for high risk rather than all patients, as it may reduce SSI after infrainguinal bypass.