Antibiotic Prophylaxis of Surgical Site Infections in Cutaneous Surgery: A Prospective Observational Study.

The use of perioperative antibiotic prophylaxis in cutaneous surgery is controversial due to unclear efficacy and, thus, potentially unnecessary side-effects. This prospective observational study analysed the efficacy of oral perioperative antibiotic prophylaxis in preventing surgical site infections. Adult patients undergoing cutaneous surgery between August 2020 and May 2021 at Ludwig-Maximilian University Hospital Munich, Germany, without prior signs of infection were eligible. Propensity score weighting was used for covariate adjustment to account for non-randomized treatment assignment. Of 758 included patients, 23 received perioperative antibiotic prophylaxis (3.0%). In this group, a surgical site infection occurred in 1 of 45 lesions (2.2%) compared with 76 of 1,189 lesions (6.5%) in the group without perioperative antibiotic prophylaxis (735 patients, 97.0%). With covariate adjustment, the odds ratio for the occurrence of a surgical site infection in patients receiving perioperative antibiotic prophylaxis was 0.114 (95% confidence interval 0.073-0.182; p <0.001) on a per lesion level. The number of lesions needed to treat to prevent 1 surgical site infection was 17.6 (95% confidence interval 16.8-19.2). This prospective observational study shows a reduction in the incidence of surgical site infection in cutaneous surgery performed with perioperative antibiotic prophylaxis. The large size difference between the 2 study groups limits the study.

Surgical site infection in skin surgery-An observational study.

BACKGROUND: Surgical site infection (SSI) has a significant impact on patients' morbidity and aesthetic results. OBJECTIVE: To identify risk factors for SSI in dermatologic surgery. PATIENTS AND METHODS: This prospective, single-centre, observational study was performed between August 2020 and May 2021. Patients that presented for dermatologic surgery were included and monitored for the occurrence of SSI. For statistical analysis, we used a mixed effects logistic regression model. RESULTS: Overall, 767 patients with 1272 surgical wounds were included in the analysis. The incidence of SSI was 6.1%. Significant risk factors for wound infection were defect size over 10cm2 (OR 3.64, 95% confidence interval [CI] 1.80-7.35), surgery of cutaneous malignancy (OR 2.96, CI 1.41-6.24), postoperative bleeding (OR 4.63, CI 1.58-13.53), delayed defect closure by local skin flap (OR 2.67, CI 1.13-6.34) and localisation of surgery to the ear (OR 7.75, CI 2.07-28.99). Wound localisation in the lower extremities showed a trend towards significance (OR 3.16, CI 0.90-11.09). Patient-related factors, such as gender, age, diabetes, or immunosuppression, did not show a statistically significant association with postoperative infection. CONCLUSION: Large defects, surgery of cutaneous malignancy, postoperative bleeding, and delayed flap closure increase the risk for SSI. High-risk locations are the ears and lower extremities.

Are Specific Body Sites Prone for Wound Infection After Skin Surgery? A Systematic Review and Meta-Analysis.

INTRODUCTION: Identifying risk factors for wound infection may guide clinical practice for optimal use of perioperative antibiotic prophylaxis in dermatologic surgery. OBJECTIVE: To summarize the current evidence whether specific body sites have higher risks for surgical site infections (SSI). METHODS: The systematic literature search included MEDLINE, Embase, CENTRAL, and trial registers. Only observational studies qualified for inclusion and meta-analysis. We assessed the risk of bias according to the Newcastle-Ottawa Scale. RESULTS: Eighteen studies with 33,086 surgical wounds were eligible. Eight studies were of good, 4 of fair, and 6 of poor quality. The mean infection rate was 4.08%. Meta-analysis showed that the lips had significantly higher infection rates. The lower extremity and ears had or tended toward a higher risk for infection, but studies were clinically heterogeneous. A large prospective trial found that surgical wounds on the hands were at higher risk for infection. The trunk showed the lowest infection rate. The risk for SSI in other body locations was not different or remained uncertain because of substantial heterogeneity among studies. CONCLUSION: Lips, lower extremities, and probably ears and hands may have a higher risk for wound infection after skin surgery. The trunk showed the lowest infection rate.

Procedure-Related Risk Factors for Surgical Site Infection in Dermatologic Surgery.

BACKGROUND: Identifying risk factors is essential for preventing surgical site infections (SSIs) in dermatologic surgery. OBJECTIVE: To analyze whether specific procedure-related factors are associated with SSI. METHODS: This systematic review of the literature included MEDLINE, EMBASE, CENTRAL, and trial registers. The Newcastle-Ottawa Scale was used for risk bias assessment. If suitable, the authors calculated risk factors and performed meta-analysis using random effects models. Otherwise, data were summarized narratively. RESULTS: Fifteen observational studies assessing 25,928 surgical procedures were included. Seven showed good, 2 fair, and 6 poor study quality. Local flaps (risk ratio [RR] 3.26, 95% confidence intervall [CI] 1.92-5.53) and skin grafting (RR 2.95, 95% CI 1.37-6.34) were associated with higher SSI rates. Simple wound closure had a significantly lower infection risk (RR 0.34, 95% CI 0.25-0.46). Second intention healing showed no association with SSI (RR 1.82, 95% CI 0.40-8.35). Delayed wound closure may not affect the SSI rate. The risk for infection may increase with the degree of preoperative contamination. There is limited evidence whether excisions >20 mm or surgical drains are linked to SSI. CONCLUSION: Local flaps, skin grafting, and severely contaminated surgical sites have a higher risk for SSI. Second intention healing and probably delayed wound closure are not associated with postoperative wound infection.

Patient-dependent risk factors for wound infection after skin surgery: A systematic review and meta-analysis.

Postoperative wound infection in dermatologic surgery causes impaired wound healing, poor cosmetic outcome and increased morbidity. Patients with a high-risk profile may benefit from perioperative antibiotic prophylaxis. The objective of this systematic review was to identify risk factors for surgical site infection after dermatologic surgery. In this article, we report findings on patient-dependent risk factors. The literature search included MEDLINE, EMBASE, CENTRAL and trial registers. We performed meta-analysis, if studies reported sufficient data to calculate risk ratios with 95% confidence intervals. Study quality was assessed according to the Newcastle-Ottawa-Scale. Seventeen observational studies that analysed 31213 surgical wounds were eligible for inclusion. Fourteen studies qualified for meta-analysis. Nine studies showed good, three fair and five poor methodological quality. The reported incidence of surgical site infection ranged from 0.96% to 8.70%. Meta-analysis yielded that male gender and immunosuppression were significantly associated with higher infection rates. There was a tendency towards a higher infection risk for patients with diabetes, without statistical significance. Meta-analysis did not show different infection rates after excision of squamous cell carcinoma or basal cell carcinoma, but studies were substantially heterogenous. There was no significant association between risk for wound infection and smoking, age over 60 years, oral anti-aggregation or anti-coagulation or excision of malignant melanoma. In conclusion, the risk for surgical site infection in dermatologic surgery is low. Infection rates were increased significantly in male as well as immunosuppressed patients and non-significantly in diabetics.

Machine Learning Based Prediction of Squamous Cell Carcinoma in Ex Vivo Confocal Laser Scanning Microscopy.

Image classification with convolutional neural networks (CNN) offers an unprecedented opportunity to medical imaging. Regulatory agencies in the USA and Europe have already cleared numerous deep learning/machine learning based medical devices and algorithms. While the field of radiology is on the forefront of artificial intelligence (AI) revolution, conventional pathology, which commonly relies on examination of tissue samples on a glass slide, is falling behind in leveraging this technology. On the other hand, ex vivo confocal laser scanning microscopy (ex vivo CLSM), owing to its digital workflow features, has a high potential to benefit from integrating AI tools into the assessment and decision-making process. Aim of this work was to explore a preliminary application of CNN in digitally stained ex vivo CLSM images of cutaneous squamous cell carcinoma (cSCC) for automated detection of tumor tissue. Thirty-four freshly excised tissue samples were prospectively collected and examined immediately after resection. After the histologically confirmed ex vivo CLSM diagnosis, the tumor tissue was annotated for segmentation by experts, in order to train the MobileNet CNN. The model was then trained and evaluated using cross validation. The overall sensitivity and specificity of the deep neural network for detecting cSCC and tumor free areas on ex vivo CLSM slides compared to expert evaluation were 0.76 and 0.91, respectively. The area under the ROC curve was equal to 0.90 and the area under the precision-recall curve was 0.85. The results demonstrate a high potential of deep learning models to detect cSCC regions on digitally stained ex vivo CLSM slides and to distinguish them from tumor-free skin.