Development of a Risk Prediction Model to Individualize Risk Factors for Surgical Site Infection After Mastectomy

Development and validation of a nomogram to predict postsurgical intra-abdominal infection in blunt abdominal trauma patients: A multicenter retrospective study

BACKGROUND

Intra-abdominal infection is a common complication of blunt abdominal trauma. Early detection and intervention can reduce the incidence of intra-abdominal infection and improve patients' prognoses. This study aims to construct a clinical model predicting postsurgical intra-abdominal infection after blunt abdominal trauma.

METHODS

This study is a retrospective analysis of 553 patients with blunt abdominal trauma from the Department of General Surgery of 7 medical centers (2011-2021). A 7:3 ratio was used to assign patients to the derivation and validation cohorts. Patients were divided into 2 groups based on whether intra-abdominal infection occurred after blunt abdominal trauma. Multivariate logistic regression and least absolute shrinkage and selection operator regression were used to select variables to establish a nomogram. The nomogram was evaluated, and the validity of the model was further evaluated by the validation cohort.

RESULTS

A total of 113 were diagnosed with intra-abdominal infection (20.4%). Age, prehospital time, C-reactive protein, injury severity score, operation duration, intestinal injury, neutrophils, and antibiotic use were independent risk factors for intra-abdominal infection in blunt abdominal trauma patients (P < .05). The area under the receiver operating curve (area under the curve) of derivation cohort and validation cohort was 0.852 (95% confidence interval, 0.784-0.912) and 0.814 (95% confidence interval, 0.751-0.902). The P value for the Hosmer-Lemeshow test was .135 and .891 in the 2 cohorts. The calibration curve demonstrated that the nomogram had a high consistency between prediction and practical observation. The decision curve analysis also showed that the nomogram had a better potential for clinical application. To facilitate clinical application, we have developed an online at https://nomogramcgz.shinyapps.io/IAIrisk/.

CONCLUSION

The nomogram is helpful in predicting the risk of postoperative intra-abdominal infection in patients with blunt abdominal trauma and provides guidance for clinical decision-making and treatment.

Timing of autologous fat grafting in implant-based breast reconstruction: Best practices based on systematic review and meta-analysis

BACKGROUND

Fat grafting is commonly undertaken as a third-stage procedure in patients with staged implant-based breast reconstruction (IBR). However, fat grafting performed during second-stage expander/implant exchange provides faster results without an additional procedure and associated risks (Patel et al., 2020). We previously demonstrated that fat grafting during second-stage expander/implant exchange did not increase clinical complications (Patel et al., 2020). As a corollary, this study investigates patients' satisfaction with second- versus third-stage fat grafting to help establish a set of best practices for the timing of fat grafting in such patients.

METHODS

A review of PubMed/MEDLINE databases (2010-2022) was performed to identify articles investigating the quality of life in patients undergoing second- or third-stage fat grafting after IBR. BREAST-Q scores were pooled using random-effects modeling and the DerSimonian-Laird method. Post-hoc sensitivity analyses were completed using the Hartung-Knapp-Sidik-Jonkman method. The Haldane-Anscombe correction was used for outcomes with low counts. All study analyses adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Six studies (216 patients) were included. Pooled random-effects modeling demonstrated no significant changes in BREAST-Q satisfaction with outcome scores when comparing patients who received second- versus third-stage fat grafting (p = 0.178) with results robust to sensitivity analyses. In addition, pooled analyses of the available data demonstrated that second-stage fat grafting did not increase downstream revision surgery needs compared to third-stage fat grafting.

CONCLUSIONS

In combination with our prior work, this meta-analysis suggests that second-stage fat grafting provides not only equivalent but improved clinical and quality of life outcomes with fewer procedures in patients undergoing expander/IBR.

External Validation of the Breast Cancer Surgery Risk Calculator (BCSRc): A Predictive Model for Postoperative Complications

BACKGROUND

The breast cancer surgical risk calculator (BCSRc) is a prognostic tool that determines a breast cancer patient's unique risk of acute complications following each possible surgical intervention. When used in the preoperative setting, it can help to stratify patients with an increased complication risk and enhance the patient-physician informed decision-making process. The objective of this study was to externally validate the four models used in the BCSRc on a large cohort of patients who underwent breast cancer surgery.

METHODS

The BCSRc was developed by using a retrospective cohort from the National Surgical Quality Improvement Program database from 2005 to 2018. Four models were built by using logistic regression methods to predict the following composite outcomes: overall, infectious, hematologic, and internal organ complications. This study obtained a new cohort of patients from the National Surgical Quality Improvement Program by utilizing participant user files from 2019 to 2020. The area under the curve, brier score, and Hosmer-Lemeshow goodness of fit test measured model performance, accuracy, and calibration, respectively.

RESULTS

A total of 192,095 patients met inclusion criteria in the development of the BCSRc, and the validation cohort included 60,144 women. The area under the curve during external validation for each model was approximately 0.70. Accuracy, or Brier scores, were all between 0.04 and 0.003. Model calibration using the Hosmer-Lemeshow statistic found all p-values > 0.05. All of these model coefficients will be updated on the web-based BCSRc platform: www.breastcalc.org .

CONCLUSIONS

The BCSRc continues to show excellent external-validation measures. Collectively, this prognostic tool can enhance the decision-making process, help stratify patients with an increased complication risk, and improve expectant management.

Individualized Risk Prediction Tool for Serious Wound Complications After Mastectomy With and Without Immediate Reconstruction

BACKGROUND

A greater proportion of patients with surgical risk factors are undergoing immediate breast reconstruction after mastectomy, resulting in the need for better risk prediction to inform decisions about the procedure. The objective of this study was to leverage clinical data to restructure a previously developed risk model to predict serious infectious and noninfectious wound complications after mastectomy alone and mastectomy plus immediate reconstruction for use during a surgical consultation.

METHODS

The study established a cohort of women age 21 years or older treated with mastectomy from 1 July 2010 to 31 December 2015 using electronic health records from two hospitals. Serious infectious and non-infectious wound complications, defined as surgical-site infection, dehiscence, tissue necrosis, fat necrosis requiring hospitalization, or surgical treatment, were identified within 180 days after surgery. Risk factors for serious wound complications were determined using modified Poisson regression, with discrimination and calibration measures. Bootstrap validation was performed to correct for overfitting.

RESULTS

Among 2159 mastectomy procedures, 1410 (65.3%) included immediate implant or flap reconstruction. Serious wound complications were identified after 237 (16.8%) mastectomy-plus-reconstruction and 30 (4.0%) mastectomy-only procedures. Independent risk factors for serious wound complications included immediate reconstruction, bilateral mastectomy, higher body mass index, depression, and smoking. The optimism-corrected C statistic of the risk prediction model was 0.735.

CONCLUSIONS

Immediate reconstruction, bilateral mastectomy, obesity, depression, and smoking were significant risk factors for serious wound complications in this population of women undergoing mastectomy. Our risk prediction model can be used to counsel women before surgery concerning their individual risk of serious wound complications after mastectomy.

National Outcomes of Prophylactic Lymphovenous Bypass during Axillary Lymph Node Dissection

BACKGROUND

 Breast cancer treatment, including axillary lymph node excision, radiation, and chemotherapy, can cause upper extremity lymphedema, increasing morbidity and health care costs. Institutions increasingly perform prophylactic lymphovenous bypass (LVB) at the time of axillary lymph node dissection (ALND) to reduce the risk of lymphedema but reports of complications are lacking. We examine records from the American College of Surgeons (ACS) National Surgery Quality Improvement Program (NSQIP) database to examine the safety of these procedures.

METHODS

 Procedures involving ALND from 2013 to 2019 were extracted from the NSQIP database. Patients who simultaneously underwent procedures with the Current Procedural Terminology (CPT) codes 38999 (other procedures of the lymphatic system), 35201 (repair of blood vessel), or 38308 (lymphangiotomy) formed the prophylactic LVB group. Patients in the LVB and non-LVB groups were compared for differences in demographics and 30-day postoperative complications including unplanned reoperation, deep vein thrombosis (DVT), wound dehiscence, and surgical site infection. Subgroup analysis was performed, controlling for extent of breast surgery and reconstruction. Multivariate logistic regression was performed to identify predictors of reoperation.

RESULTS

 The ALND without LVB group contained 45,057 patients, and the ALND with LVB group contained 255 (0.6%). Overall, the LVB group was associated with increased operative time (288 vs. 147 minutes, p < 0.001) and length of stay (1.7 vs. 1.3 days, p < 0.001). In patients with concurrent mastectomy without immediate reconstruction, the LVB group had a higher rate of DVTs (3.0 vs. 0.2%, p = 0.009). Reoperation, wound infection, and dehiscence rates did not differ across subgroups. Multivariate logistic regression showed that LVB was not a predictor of reoperations.

CONCLUSION

 Prophylactic LVB at time of ALND is a generally safe and well-tolerated procedure and is not associated with increased reoperations or wound complications. Although only four patients in the LVB group had DVTs, this was a significantly higher rate than in the non-LVB group and warrants further investigation.

Does the Duration of Perioperative Antibiotic Prophylaxis Influence the Incidence of Postoperative Surgical-Site Infections in Implant-Based Breast Reconstruction in Women with Breast Cancer? A Retrospective Study

BACKGROUND

Perioperative antibiotic prophylaxis is an established concept to reduce the risk of surgical-site infections; however, the optimal treatment duration in prosthetic breast reconstruction is still controversial. This study evaluated a potential association between the perioperative antibiotic prophylaxis duration (≤24 hours versus >24 hours) and incidence of postoperative surgical-site infections in immediate implant-based breast reconstruction in breast cancer patients.

METHODS

A descriptive, retrospective analysis of surgical-site infections after immediate implant-based breast reconstruction in breast cancer patients between January of 2011 and December of 2018 was performed. The incidence of postoperative surgical-site infections in patients with more than 24 hours of perioperative antibiotic prophylaxis was compared to patients treated for 24 hours or less.

RESULTS

A total of 240 patients who met criteria were included. There were no relevant epidemiologic, clinical, or histopathologic differences between groups. Surgical-site infections as defined by the Centers for Disease Control and Prevention criteria occurred in 25.8 percent. A risk factor-adjusted analysis by a prespecified multiple logistic regression model showed that 24 hours or less of perioperative antibiotic prophylaxis was not inferior to treatment for more than 24 hours. The upper limit of the one-sided 95 percent confidence interval of the risk difference was 9.4 percent (below the prespecified noninferiority margin of 10 percent leading to statistical significance). Risk factors for a surgical-site infection included obesity and postoperative wound complications.

CONCLUSIONS

The study found no association between short-course perioperative antibiotic prophylaxis (≤24 hours) and an increased rate of postoperative surgical-site infection. This is of high clinical relevance because short-course treatment can help reduce side effects and the emergence of antimicrobial resistance and prevent surgical-site infections as effectively as a prolonged perioperative antibiotic prophylaxis course.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Complication Differences Between the Tumescent and Non-Tumescent Dissection Techniques for Mastectomy: A Meta-Analysis

Purpose

We conducted a systematic literature search and pooled data from studies to compare the incidence of complications between the tumescent and non-tumescent techniques for mastectomy.

Methods

We searched PubMed, Embase, BioMed Central, Ovid, and CENTRAL databases for studies comparing the two mastectomy techniques up to November 1^st, 2020. We used a random-effects model to calculate odds ratios (OR) with 95% confidence intervals (CI).

Results

Nine studies were included with one randomized controlled trial (RCT). Meta-analysis indicated no statistically significant difference in the incidence of total skin necrosis (OR 1.18 95% CI 0.71, 1.98 I² = 82% p=0.52), major skin necrosis (OR 1.58 95% CI 0.69, 3.62 I² = 71% p=0.28), minor skin necrosis (OR 1.11 95% CI 0.43, 2.85 I² = 72% p=0.83), hematoma (OR 1.19 95% CI 0.80, 1.79 I² = 4% p=0.39), and infections (OR 0.87 95% CI 0.54, 1.40 I² = 54% p=0.56) between tumescent and non-tumescent groups. Analysis of studies using immediate alloplastic reconstruction revealed no statistically significant difference in the incidence of explantation between the two groups (OR 0.78 95% CI 0.46, 1.34 I² = 62% p=0.37). Multivariable-adjusted ORs on total skin necrosis were available from three studies. Pooled analysis indicated no statistically significant difference between tumescent and non-tumescent groups (OR 1.72 95% CI 0.72, 4.13 I² = 87% p=0.23).

Conclusion

Low-quality evidence derived mostly from non-randomized studies is indicative of no difference in the incidence of skin necrosis, hematoma, seroma, infection, and explantation between the tumescent and non-tumescent techniques of mastectomy. There is a need for high-quality RCTs to further strengthen the evidence.

Do Preoperative Prophylactic Antibiotics Reduce Surgical Site Infection Following Wire-Localized Lumpectomy? A Single-Blind Randomized Clinical Trial

BACKGROUND

Data on the benefits of preoperative prophylactic antibiotics for breast surgery are conflicting, and there is no specific guideline for their use in wire-localized lumpectomy.

PATIENTS AND METHODS

This is a proof-of-concept, single-blind randomized controlled trial carried out from April 2018 to June 2019 at the Centre des Maladies du Sein du CHU de Québec - Université Laval. The objectives were to determine whether a single dose of preoperative antibiotics reduces surgical site infection (SSI) after wire-localized lumpectomy and to identify the risk factors for SSI. The patients were randomized to receive preoperative prophylactic antibiotics or not. SSI was defined by positive breast wound cultures, abscess drainage, and/or antibiotics given for clinical signs of breast infection within 30 days of the operation. This study was registered with ClinicalTrials.gov, NCT04818931.

RESULTS

A total of 330 patients were enrolled. Eighteen patients were excluded. The SSI rate was 3.1% (5/160) in the antibiotic group versus 5.9% (9/152) in the control group (p = 0.28). Only obesity was a significant risk factor for SSI. All cases of SSI were treated routinely with antibiotics; one patient required wound re-opening. None of the SSIs delayed the adjuvant treatment.

CONCLUSION

Preoperative antibiotic prophylaxis does not significantly decrease the occurrence of breast SSI. It is safe to omit prophylactic antibiotics for a wire-localized lumpectomy. This could also decrease the treatment costs and avoid unnecessary side effects.

Surgical Predictive Model for Breast Cancer Patients Assessing Acute Postoperative Complications: The Breast Cancer Surgery Risk Calculator

BACKGROUND

Prognostic tools, such as risk calculators, improve the patient-physician informed decision-making process. These tools are limited for breast cancer patients when assessing surgical complication risk preoperatively.

OBJECTIVE

In this study, we aimed to assess predictors associated with acute postoperative complications for breast cancer patients and then develop a predictive model that calculates a complication probability using patient risk factors.

METHODS

We performed a retrospective cohort study using the National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2017. Women diagnosed with ductal carcinoma in situ or invasive breast cancer who underwent either breast conservation or mastectomy procedures were included in this predictive modeling scheme. Four models were built using logistic regression methods to predict the following composite outcomes: overall, infectious, hematologic, and internal organ complications. Model performance, accuracy and calibration measures during internal/external validation included area under the curve, Brier score, and Hosmer-Lemeshow statistic, respectively.

RESULTS

A total of 163,613 women met the inclusion criteria. The area under the curve for each model was as follows: overall, 0.70; infectious, 0.67; hematologic, 0.84; and internal organ, 0.74. Brier scores were all between 0.04 and 0.003. Model calibration using the Hosmer-Lemeshow statistic found all p-values to be > 0.05. Using model coefficients, individualized risk can be calculated on the web-based Breast Cancer Surgery Risk Calculator (BCSRc) platform ( www.breastcalc.org ).

CONCLUSION

We developed an internally and externally validated risk calculator that estimates a breast cancer patient's unique risk of acute complications following each surgical intervention. Preoperative use of the BCSRc can potentially help stratify patients with an increased complication risk and improve expectations during the decision-making process.

Higher age, female gender, osteoarthritis and blood transfusion protect against periprosthetic joint infection in total hip or knee arthroplasties: a systematic review and meta-analysis

PURPOSE

The goal of this systematic review and meta-analysis was to identify the main risk factors for periprosthetic joint infection (PJI) in patients undergoing total hip or knee arthroplasties.

METHODS

A systematic review was conducted of the potential risk factors for PJI in total hip or total knee arthroplasty. Risk factors were compared and grouped according to demographics, comorbidities, behavior, infections, native joint diseases and other patient-related and procedure-related factors. Meta-analysis (random-effects models) was conducted using odds ratio (OR) and mean difference (MD). Risk of bias (ROBBINS-I) and strength of the evidence (GRADE) were assessed.

RESULTS

The study included 37 studies (2,470,827 patients). Older age was a protective factor (MD = - 1.18). Male gender (OR 1.34), coagulopathy (3.05), congestive heart failure (2.36), diabetes mellitus (1.80), obesity (1.61), systemic neoplasia (1.57), chronic lung disease (1.52), and hypertension (1.21) increased the risk for PJI. Behavioral risk factors comprised alcohol abuse (2.95), immunosuppressive therapy (2.81), steroid therapies (1.88), and tobacco (1.82). Infectious risk factors included surgical site infections (6.14), postoperative urinary tract infections (2.85), and prior joint infections (2.15). Rheumatoid arthritis, posttraumatic native joint disease, high National Nosocomial Infections Surveillance (NNIS) system surgical patient index score, prior joint operation, American Society of Anesthesiologists score ≥ 3 and obesity were also significantly associated with higher risk of PJI. Osteoarthritis and blood transfusion were protective factors.

CONCLUSIONS

The main risk factors for PJI in each category were male gender, coagulopathy, alcohol abuse, surgical site infection (highest score) and high NNIS system surgical patient index score. Protective factors were age, female gender in TKA, osteoarthritis and blood transfusion. Optimization of modifiable risk factors for PJI should be attempted in clinical practice.

LEVEL OF EVIDENCE

II.

Antibiotic prophylaxis in breast cancer surgery. A randomized controlled trial

Purpose

To assess the effect of antibiotic prophylaxis on surgical site infection (SSI) rates in women undergoing breast cancer surgery in two tertiary hospitals in Brazil.

Methods

This was a randomized, double-blind, placebo-controlled, parallel-group clinical trial. A total of 124 women without independent risk factors for SSI were randomly assigned to receive either cefazolin (antibiotic group, n = 62) or placebo (control group, n = 62) as preoperative prophylaxis. After surgery, all surgical wounds were examined once a week, for four weeks, according to the Centers for Disease Control and Prevention definitions and classifications for SSI.

Results

Baseline characteristics were homogeneous between the two groups. Only one patient in the antibiotic group developed SSI, which was classified as superficial incisional. The overall SSI rate was low, with no significant difference between groups.

Conclusion

Antibiotic prophylaxis had no significant effect on reducing SSI rates in women without independent risk factors for SSI undergoing breast cancer surgery.

Oncological safety and complication risks of mastectomy with or without breast reconstruction: A Bayesian analysis

BACKGROUND

Currently, breast cancer patients undergoing mastectomy (MA) have three surgical options: MA only and reconstruction at the time of MA ("immediate," IBR) or at a later time ("delayed," DBR). To assess the oncological safety and complication risks associated with different surgical choices, a systematic review with Bayesian network analysis was conducted.

METHODS

Cochrane library, PubMed/MEDLINE, EMBASE, and the China National Knowledge Infrastructure were systematically searched in November 2019. The odds ratios [OR] were estimated for oncological safety (including disease-free survival, overall survival, local recurrence, and distant metastases) and complication risks (including overall complications, surgical site infection, and lymphedema) among MA, IBR, and DBR groups.

RESULTS

In the included 51 studies (265,522 patients), reconstruction after MA for IBR or DBR was associated with increased overall survival compared to simple MA (DBR vs. MA: OR 4.12, 95% credible interval [CrI] 1.80-10.01; IBR vs. MA: OR 1.75, 95% CrI 1.32-2.32). Additionally, IBR was associated with a decreased distant metastasis rate compared to MA (IBR vs. MA: OR 0.67, 95% CrI 0.51-0.90). However, the risk of overall complications and surgical site infection was higher in the IBR group than in the other two groups (complications, IBR vs. DBR: OR 1.40, 95% CrI 1.01-1.93; surgical site infection, IBR vs. MA: OR 1.77, 95% CrI 1.03-3.13).

CONCLUSIONS

Evidence suggested that breast reconstruction, whether IBR or DBR, does not adversely affect oncological safety in the setting of breast cancer. IBR is associated with an increased risk of overall complications and surgical site infection, but technical advances in this surgical procedure have cumulated over time.

WITHDRAWN: Analysis of Infection Factors after Radical Mastectomy for Breast Cancer by CT Image and AUTO-plan Intelligent Analysis under Regional Nerve Block

This article has been withdrawn at the request of the Editor-in-Chief. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

A Randomized Controlled Trial Evaluating the BREASTChoice Tool for Personalized Decision Support About Breast Reconstruction After Mastectomy

OBJECTIVE

To evaluate a web-based breast reconstruction decision aid, BREASTChoice.

SUMMARY AND BACKGROUND DATA

Although postmastectomy breast reconstruction can restore quality of life and body image, its morbidity remains substantial. Many patients lack adequate knowledge to make informed choices. Decisions are often discordant with patients' preferences.

METHODS

Adult women with stages 0-III breast cancer considering postmastectomy breast reconstruction with no previous reconstruction were randomized to BREASTChoice or enhanced usual care (EUC).

RESULTS

Three hundred seventy-six patients were screened; 120 of 172 (69.8%) eligible patients enrolled. Mean age = 50.7 years (range 25-77). Most were Non-Hispanic White (86.3%) and had a college degree (64.3%). Controlling for health literacy and provider seen, BREASTChoice users had higher knowledge than those in EUC (84.6% vs. 58.2% questions correct; P < 0.001). Those using BREASTChoice were more likely to know that reconstruction typically requires more than 1 surgery, delayed reconstruction lowers one's risk, and implants may need replacement over time (all ps < 0.002). BREASTChoice compared to EUC participants also felt more confident understanding reconstruction information (P = 0.009). There were no differences between groups in decisional conflict, decision process quality, shared decision-making, quality of life, or preferences (all ps > 0.05). There were no differences in consultation length between BREASTChoice and EUC groups (mean = 29.7 vs. 30.0 minutes; P > 0.05). BREASTChoice had high usability (mean score = 6.3/7). Participants completed BREASTChoice in about 27 minutes.

CONCLUSIONS

BREASTChoice can improve breast reconstruction decision quality by improving patients' knowledge and providing them with personalized risk estimates. More research is needed to facilitate point-of-care decision support and examine BREASTChoice's impact on patients' decisions over time.

The Impact of Delaying Breast Reconstruction on Patient Expectations and Health-Related Quality of Life: An Analysis Using the BREAST-Q

Purpose

An understanding of patient expectations predicts better health outcomes following breast reconstruction. No study to date has examined how patient expectations for breast reconstruction and preoperative health-related quality of life vary with time since breast cancer diagnosis.

Methods

Women consulting for breast reconstruction to a single surgeon's practice over a 13-month period were enrolled in this cross-sectional study. Patients were asked to prospectively complete the BREAST-Q expectations and preoperative reconstruction modules. A retrospective chart review was then performed on eligible patients, and patient demographics, cancer-related factors, and comorbidities were collected. BREAST-Q scores were transformed using the equivalent Rasch method. Multivariate linear regression models were constructed to assess the association between BREAST-Q scores and time since cancer diagnosis.

Results

Sixty-five patients met inclusion criteria for analysis and are characterized by a mean age of 53 ± 11 (34-79) years and a mean body mass index of 28 ± 6 (19-49). Most patients were treated by mastectomy (58%) or lumpectomy (23%). At the time of retrospective chart review, 29 (43%) patients had undergone reconstruction, most of which were delayed (59%). The mean latency from cancer diagnosis to reconstruction was 685 ± 867 days (range: 28-3322 days). Latency from cancer diagnosis to reconstruction was associated with a greater expectation of pain (β = 0.5; standard error [SE] = 0.005; 95% confidence interval [CI]: 0.003-0.027; P < .05), and a slower expectation for recovery (β = -0.5; SE = 0.004; 95% CI: -0.021 to -0.001; P < .05) after breast reconstruction. Latency from cancer diagnosis to reconstruction was associated with an increase in preoperative psychosocial well-being (β = 0.578; SE 0.009; 95% CI: 0.002-0.046; P < .05).

Conclusion

Delaying breast reconstruction may negatively impact patient expectations of postoperative pain and recovery. Educational interventions aimed at understanding and managing patient expectations in the preoperative period may improve health-related quality of life and patient-related outcomes following initial breast cancer surgery.

Validation of predictive factors for infection in adults with chronic leg ulcers: A prospective longitudinal study

AIMS AND OBJECTIVES

To validate the ability of factors to predict infection in adults with chronic leg ulcers over a 12-week period.

BACKGROUND

Leg ulcers affect ~3% of older adults and are often hard to heal. Infection is a leading contributor for delayed healing, causing delayed wound healing, increased hospitalisation, increased healthcare costs and reduced patient quality of life. The importance of early identification of infection has been highlighted for decades, yet little is known about factors that are associated with increased risk of infection in this specific population.

DESIGN

A longitudinal, prospective observational study in a single centre.

METHODS

Between August 2017 and May 2018, a total of 65 adults with chronic leg ulcers were prospectively observed for a 12-week period. Patients were recruited from an outpatient wound clinic at a tertiary hospital in Australia. Data were collected from recruitment (baseline) and each visit (weekly or fortnightly) up until 12 weeks. Descriptive statistics were calculated for all variables. A Cox proportional hazards regression model was used to identify predictive factors for infection. The TRIPOD guidelines for reporting were followed (See Data S1).

RESULTS

The sample consisted of 65 adults with chronic leg ulcers, and 9.2% of these had their ulcer infected at baseline. Two predictive factors, using walking aids and gout, were found to be significantly related to increased likelihood of developing infection within 12 weeks.

CONCLUSION

The present study showed that patients who either used walking aids or were diagnosed with gout were at greater risk of infection compared to those without these factors.

RELEVANCE TO CLINICAL PRACTICE

These findings provide new information for clinicians in early identification of patients at risk of infection, and for patients in enhancing their awareness of their own risk.

Can We Improve Prediction of Adverse Surgical Outcomes? Development of a Surgical Complexity Score Using a Novel Machine Learning Technique

BACKGROUND

An optimal method to quantify surgical complexity using patient comorbidities derived from administrative billing data is lacking. We sought to develop a novel, easy-to-use surgical Complexity Score to accurately predict adverse outcomes among patients undergoing elective surgery.

STUDY DESIGN

A novel surgical Complexity Score was developed using 100% Medicare Inpatient and Outpatient Standard Analytic Files (SAFs) from years 2012 to 2016 (n = 1,049,160). Comorbid conditions were entered into a machine learning algorithm to assign weights to maximize the correlation with multiple postoperative outcomes including morbidity, readmission, mortality, and postoperative super-use. Predictive ability was compared against 3 of the most commonly used risk adjustment indices: the Charlson Comorbidity Index (CCI), Elixhauser Comorbidity Index (ECI), and the Centers for Medicare and Medicaid Service's Hierarchical Condition Category (CMS-HCC).

RESULTS

Patients underwent colectomy (12.6%), abdominal aortic aneurysm repair (4.4%), coronary artery bypass grafting (13.0%), total hip replacement (22.0%), total knee replacement (43.0%), or lung resection (5.0%). The Complexity Score had a good to very good predictive ability for all adverse outcomes. The Complexity Score had the highest accuracy in predicting perioperative morbidity (area under the curve [AUC]: 0.868, 95% CI 0.866 to 0.869); this performed better than the CCI (AUC: 0.717, 95% CI 0.715 to 0.719), ECI (AUC: 0.799, 95% CI 0.797 to 0.800), and similar to the CMS-HCC (AUC: 0.862, 95% CI 0.861 to 0.863). Similarly, the Complexity Score outperformed each of the 3 other comorbidity indices in predicting 90-day readmission (AUC: 0.707, 95% CI 0.705 to 0.709), 30-day readmission (AUC: 0.717, 95% CI 0.715 to 0.720), and postoperative super-use (AUC: 0.817, 95% CI 0.814 to 0.820).

CONCLUSIONS

Compared with the most commonly used comorbidity and surgical risk scores, the novel surgical Complexity Score outperformed the CCI, ECI, and CMS-HCC in predicting postoperative morbidity, 30-day readmission, 90-day readmission, and postoperative super-use.

Immediate Implant-Based Breast Reconstruction with Acellular Dermal Matrix: A Comparison of Sterile and Aseptic AlloDerm in 2039 Consecutive Cases

BACKGROUND

Sterile ready-to-use acellular dermal matrix, introduced as an alternative to aseptic freeze-dried acellular dermal matrix for implant-based breast reconstruction, has been investigated in a limited number of studies. This study compared outcomes in implant-based breast reconstruction with ready-to-use and freeze-dried acellular dermal matrix.

METHODS

The authors analyzed patients undergoing implant-based breast reconstruction with either freeze-dried or ready-to-use acellular dermal matrix, including demographics, clinical variables, and outcomes. An a priori power analysis was performed and logistic regression modeling was used to quantify the effect of acellular dermal matrix on outcomes while controlling for potential confounders.

RESULTS

A total of 1285 consecutive patients undergoing 2039 immediate prosthetic breast reconstructions constituted the population: 612 (n = 910 breasts) with freeze-dried matrix and 673 (n = 1129 breasts) with ready-to-use acellular dermal matrix. The freeze-dried matrix cohort had a significantly higher rate of explantation compared with the ready-to-use matrix cohort (18.0 percent versus 12.0 percent; p = 0.0036), but surgical-site infection, wound dehiscence, mastectomy flap necrosis, seroma, and hematoma did not differ significantly between groups. On multivariate regression, patients undergoing reconstruction with freeze-dried matrix, compared to ready-to-use matrix, did not have higher odds of experiencing surgical-site infections (OR, 1.064; p = 0.7455), but did have higher odds of explantation (OR, 1.570; p = 0.0161). Tobacco use (OR, 2.809; p = 0.0002) and body mass index (OR, 1.054; p < 0.0001) were also independent predictors of explantation.

CONCLUSION

Immediate implant-based breast reconstruction with sterile ready-to-use acellular dermal matrix has a comparable overall safety profile and a lower rate of prosthetic explantations compared with aseptic freeze-dried acellular dermal matrix.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Predicting nosocomial lower respiratory tract infections by a risk index based system

Although belonging to one of the most common type of nosocomial infection, there was currently no simple prediction model for lower respiratory tract infections (LRTIs). This study aims to develop a risk index based system for predicting nosocomial LRTIs based on data from a large point-prevalence survey. Among the 49328 patients included, the prevalence of nosocomial LRTIs was 1.70% (95% confidence interval [CI], 1.64% to 1.76%). The areas under the receiver operating characteristic (ROC) curve for logistic regression and fisher discriminant analysis were 0.907 (95% CI, 0.897 to 0.917) and 0.902 (95% CI, 0.892 to 0.912), respectively. The constructed risk index based system also displayed excellent discrimination (area under the ROC curve: 0.905 [95% CI, 0.895 to 0.915]) to identify LRTI in internal validation. Six risk levels were generated according to the risk score distribution of study population, ranging from 0 to 5, the corresponding prevalence of nosocomial LRTIs were 0.00%, 0.39%, 3.86%, 12.38%, 28.79% and 44.83%, respectively. The sensitivity and specificity of prediction were 0.87 and 0.79, respectively, when the best cut-off point of risk score was set to 14. Our study suggested that this newly constructed risk index based system might be applied to boost more rational infection control programs in clinical settings.

Comparison of Wound Complications After Immediate, Delayed, and Secondary Breast Reconstruction Procedures

Importance

Few data are available concerning surgical site infection (SSI) and noninfectious wound complications (NIWCs) after delayed (DR) and secondary reconstruction (SR) compared with immediate reconstruction (IR) procedures in the breast.

Objective

To compare the incidence of SSI and NIWCs after implant and autologous IR, DR, and SR breast procedures after mastectomy.

Design, Setting, and Participants

This retrospective cohort study included women aged 18 to 64 years undergoing mastectomy from January 1, 2004, through December 31, 2011. Data were abstracted from a commercial insurer claims database in 12 states and analyzed from January 1, 2015, through February 7, 2017.

Exposures

Reconstruction within 7 days of mastectomy was considered immediate. Reconstruction more than 7 days after mastectomy was considered delayed if the mastectomy did not include IR or secondary if the mastectomy included IR.

Main Outcomes and Measures

International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes for SSI and NIWCs.

Results

Mastectomy was performed in 17 293 women (mean [SD] age, 50.4 [8.5] years); 61.4% of women had IR or DR. Among patients undergoing implant reconstruction, the incidence of SSI was 8.9% (685 of 7655 women) for IR, 5.7% (21 of 369) for DR, and 3.2% (167 of 5150) for SR. Similar results were found for NIWCs. In contrast, the incidence of SSI was similar after autologous IR (9.8% [177 of 1799]), DR (13.9% [19 of 137]), and SR (11.6% [11 of 95]) procedures. Compared with women without an SSI after implant IR, women with an SSI after implant IR were significantly more likely to have another SSI (47 of 412 [11.4%] vs 131 of 4791 [2.7%]) and an NIWC (24 of 412 [5.8%] vs 120 of 4791 [2.5%]) after SR. The incidence of SSI (24 of 379 [6.3%] vs 152 of 5286 [2.9%]) and NIWC (22 of 379 [5.8%] vs 129 of 5286 [2.4%]) after implant SR was higher in women who had received adjuvant radiotherapy. Wound complications after IR were associated with significantly more breast surgical procedures (mean of 1.92 procedures [range, 0-9] after implant IR and 1.11 [range, 0-6] after autologous IR) compared with women who did not have a complication (mean of 1.37 procedures [range, 0-8] after implant IR and 0.87 [range, 0-6] after autologous IR).

Conclusions and Relevance

The incidence of SSI and NIWCs was slightly higher for implant IR compared with delayed or secondary implant reconstruction. Women who had an SSI or NIWC after implant IR had a higher risk for subsequent complications after SR and more breast operations. The risk for complications should be carefully balanced with the psychosocial and technical benefits of IR. Select high-risk patients may benefit from consideration of delayed rather than immediate implant reconstruction to decrease breast complications after mastectomy.

Prevalence and Predictors of Postdischarge Antibiotic Use Following Mastectomy

OBJECTIVE Survey results suggest that prolonged administration of prophylactic antibiotics is common after mastectomy with reconstruction. We determined utilization, predictors, and outcomes of postdischarge prophylactic antibiotics after mastectomy with or without immediate breast reconstruction. DESIGN Retrospective cohort. PATIENTS Commercially insured women aged 18-64 years coded for mastectomy from January 2004 to December 2011 were included in the study. Women with a preexisting wound complication or septicemia were excluded. METHODS Predictors of prophylactic antibiotics within 5 days after discharge were identified in women with 1 year of prior insurance enrollment; relative risks (RR) were calculated using generalized estimating equations. RESULTS Overall, 12,501 mastectomy procedures were identified; immediate reconstruction was performed in 7,912 of these procedures (63.3%). Postdischarge prophylactic antibiotics were used in 4,439 procedures (56.1%) with immediate reconstruction and 1,053 procedures (22.9%) without immediate reconstruction (P.05). CONCLUSIONS Prophylactic postdischarge antibiotics are commonly prescribed after mastectomy; immediate reconstruction is the strongest predictor. Stewardship efforts in this population to limit continuation of prophylactic antibiotics after discharge are needed to limit antimicrobial resistance. Infect Control Hosp Epidemiol 2017;38:1048-1054.

Surveillance and Prevention of Surgical Site Infections in Breast Oncologic Surgery with Immediate Reconstruction

Surgical site infection (SSI) after immediate breast reconstruction is much more common than would be expected after a clean surgical procedure. Although the SSI rates reported in individual studies are quite variable, there are no obvious explanations for the variation in infection rates between institutions. The microbiology of these SSIs is unusual, with higher proportions of infections caused by atypical Myobacterium species and Gram-negative bacilli than would be expected for this anatomic site. In an effort to prevent SSIs, many surgeons use a variety of different practices including irrigation and soaking of implants with antibiotic solutions and prolonged duration of prophylactic antibiotics, although the literature to support these practices is very sparse. In particular, prolonged use of antibiotics post-discharge is concerning due to the potential for harm, including increased risk of Clostridium difficile infection, development of antibiotic resistant organisms, and drug-related allergic reactions. With higher rates of mastectomy and breast implant reconstruction in women with early-stage breast cancer, including greater utilization of reconstruction in higher-risk individuals, the number of women suffering from infection after oncologic reconstruction will likely continue to increase. It is imperative that more research be done to identify modifiable factors associated with increased risk of infection. It is also essential that larger studies with rigorous study designs be performed to identify optimal strategies to decrease the risk of SSI in this vulnerable population.

Patients at High-Risk for Surgical Site Infection

BACKGROUND

Surgical site infections (SSIs) are a significant healthcare quality issue, resulting in increased morbidity, disability, length of stay, resource utilization, and costs. Identification of high-risk patients may improve pre-operative counseling, inform resource utilization, and allow modifications in peri-operative management to optimize outcomes.

METHODS

Review of the pertinent English-language literature.

RESULTS

High-risk surgical patients may be identified on the basis of individual risk factors or combinations of factors. In particular, statistical models and risk calculators may be useful in predicting infectious risks, both in general and for SSIs. These models differ in the number of variables; inclusion of pre-operative, intra-operative, or post-operative variables; ease of calculation; and specificity for particular procedures. Furthermore, the models differ in their accuracy in stratifying risk. Biomarkers may be a promising way to identify patients at high risk of infectious complications.

CONCLUSIONS

Although multiple strategies exist for identifying surgical patients at high risk for SSIs, no one strategy is superior for all patients. Further efforts are necessary to determine if risk stratification in combination with risk modification can reduce SSIs in these patient populations.

Diagnosis and management of skin and soft tissue infections in the intensive care unit: a review

PURPOSE

To review the salient features of the diagnosis and management of the most common skin and soft tissue infections (SSTI). This review focuses on severe SSTIs that require care in an intensive care unit (ICU), including toxic shock syndrome, myonecrosis/gas gangrene, and necrotizing fasciitis.

METHODS

Guidelines, expert opinion, and local institutional policies were reviewed.

RESULTS

Severe SSTIs are common and their management complex due to regional variation in predominant pathogens and antimicrobial resistance patterns, as well as variations in host immune responses. Unique aspects of care for SSTIs in the ICU are discussed, including the role of prosthetic devices, risk factors for bacteremia, and the need for surgical consultation. SSTI mimetics, the role of dermatologic consultation, and the unique features of SSTIs in immunocompromised hosts are also described.

CONCLUSIONS

We provide recommendations for clinicians regarding optimal SSTI management in the ICU setting.