Antibiotic Prophylaxis for Breast Oncosurgery in a Setting With a High Prevalence of Multidrug-Resistant Bacteria: Common Sense Infection Control Measures Are More Important Than Prolonged Antibiotics

Beyond CDC-Defined Surgical Site Infection: Factors Associated with Antibiotic Prescription After Breast Operation

Background: Most studies on surgical site infections (SSIs) use the US Centers for Disease Control and Prevention (CDC) guidelines, which excludes inflammation or cellulitis without fever. The aim of this study was to evaluate antibiotic prescription trends in the post-operative period among patients undergoing breast operation. We explore the outcomes of patients receiving antibiotic agents outside of the CDC-defined SSI. Patients and Methods: A retrospective review of patients undergoing breast operation from January 2021 to May 2021 was conducted. Solely reconstructive and cosmetic cases were excluded. The primary outcome was the prevalence of antibiotic prescription in the absence of CDC-defined SSI, excluding routine prophylactic antibiotic agents, with analysis of associated factors. Results: A total of 754 breast surgical procedures were included. Seventy-seven patients (10.2%) were prescribed outpatient antibiotic agents. CDC-defined SSI occurred in 5.3% (n = 40), mostly involving tissue expander/implant-based reconstruction (47.5%, n = 19). However, 37 (4.9%) did not progress to meet the CDC criteria for SSI. Patients prescribed outpatient antibiotic agents without CDC-defined SSI did not have increased rates of diabetes mellitus, obesity, or current smoking. These patients were more likely to have a surgical drain (48.6% vs. 28.4%, p = 0.02), plastic surgery involvement (32.4% vs. 18.0%, p = 0.048), and a post-operative seroma (32.4% vs. 8.1%, p < 0.001) and or or cellulitis (18.9% vs. 0%, p < 0.001). Conclusion: Patients are prescribed antibiotic agents after breast operation based on clinical judgment for indications other than CDC-defined SSI. Post-operative wound morbidity including seroma and cellulitis could be contributing to these antibiotic prescriptions. Further study is needed to determine whether providers are preemptively treating SSIs appropriately or over-treating non-infectious wound complications.

Establishment and Validation of Models for the Risk of Multi-Drug Resistant Bacteria Infection and Prognosis in Elderly Patients with Pulmonary Infection: A Multicenter Retrospective Study

Purpose

The aim of this study was to establish risk prediction and prognosis models for multidrug-resistant bacterial infections (MDRB) in elderly patients with pulmonary infections in a multicenter setting.

Patients and Methods

This study is a retrospective cohort analysis in Anhui province of China. Data dimension reduction and feature selection were performed using the lasso regression model. Multifactorial regression analysis to identify risk factors associated with MDRB infection and prognosis. The relevant risks of each patient in the prognostic training cohort were scored based on prognostic independent risk factors. Subsequently, patients were classified into high-risk and low-risk groups, and survival differences were compared between them. Finally, models were established based on independent risk factors for infection, risk groups, and independent prognostic factors, and were presented on nomograms. The predictive accuracy of the model was assessed using corresponding external validation set data.

Results

The study cohort comprised 994 elderly patients with pulmonary infection. Multivariate analysis revealed that endotracheal intubation, previous antibiotic use beyond 2 weeks, and concurrent respiratory failure or cerebrovascular disease were independent risk factors associated with the incidence of MDRB infection. Cox regression analysis identified respiratory failure, malnutrition, an APACHE II score of at least 20, and higher blood creatinine levels as independent prognostic risk factors. The models were validated using an external validation dataset from multiple centers, which demonstrated good diagnostic ability and a good fit with a fair benefit.

Conclusion

In conclusion, our study provides an appropriate and generalisable assessment of risk factors affecting infection and prognosis in patients with MDRB, contributing to improved early identification of patients at higher risk of infection and death, and appropriately guiding clinical management.