Mismatch Rate of Empirical Antimicrobial Treatment in Fracture-Related Infections.

OBJECTIVES: To evaluate the current standard of care regarding empirical antimicrobial therapy in fracture-related infections (FRIs). DESIGN: Retrospective cohort study. SETTING: Level I Trauma Center. PATIENT SELECTION CRITERIA: Adult patients treated for FRI with surgical debridement and empirical antibiotics between September 1, 2014, and August 31, 2022. Patients were excluded if less than 5 tissue samples for culture were taken, culture results were negative, or there was an antibiotic-free window of less than 3 days before debridement. OUTCOME MEASURES AND COMPARISONS: FRI microbial etiology, antimicrobial resistance patterns (standardized antimicrobial panels were tested for each pathogen), the mismatch rate between empirical antimicrobial therapy and antibiotic resistance of causative microorganism(s), and mismatching risk factors. RESULTS: In total, 75 patients were included [79% (59/75) men, mean age 51 years]. The most prevalent microorganisms were Staphylococcus aureus (52%, 39/75) and Staphylococcus epidermidis (41%, 31/75). The most frequently used empirical antibiotic was clindamycin (59%, 44/75), followed by combinations of gram-positive and gram-negative covering antibiotics (15%, 11/75). The overall mismatch rate was 51% (38/75) [95% confidence interval (CI), 0.39-0.62] and did not differ between extremities [upper: 31% (4/13) (95% CI, 0.09-0.61), lower: 55% (33/60) (95% CI, 0.42-0.68, P = 0.11)]. Mismatching empirical therapy occurred mostly in infections caused by S. epidermidis and gram-negative bacteria. Combination therapy of vancomycin with ceftazidime produced the lowest theoretical mismatch rate (8%, 6/71). Polymicrobial infections were an independent risk factor for mismatching (OR: 8.38, 95% CI, 2.53-27.75, P < 0.001). CONCLUSIONS: In patients with FRI, a mismatching of empirical antibiotic therapy occurred in half of patients, mainly due to lack of coverage for S. epidermidis , gram-negative bacteria, and polymicrobial infections. Empirical therapy with vancomycin and ceftazidime produced the lowest theoretical mismatch rates. This study showed the need for the consideration of gram-negative coverage in addition to standard broad gram-positive coverage. Future studies should investigate the effect of the proposed empirical therapy on long-term outcomes. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

An innovative assessment tool for evaluating narrative feedback quality among Medicine and Biomedical Sciences students.

Objectives: To develop a reliable instrument to objectively assess feedback quality, to use it for assessment of the quality of students' narrative feedback and to be used as a self-assessment instrument for students in their learning process. Methods: In a retrospective cohort study, 635 feedback narratives, provided by small groups of Medicine and Biomedical Sciences undergraduate students, have been extracted from available quarterly curriculum evaluation surveys. A rubric was developed based on literature and contents of our feedback education. It consists of seven subitems and has a maximum score of 20 points (sufficient score: >10 points). Rubric reliability was evaluated using intra-class correlation. The rubric was tested by analysing the feedback narratives. To test progression, we compared rubric scores between study years with a Kruskal-Wallis analysis and Dunn's post-hoc testing with Bonferroni correction. Results: The rubric has an intra-class correlation of 0.894. First year students had a mean rubric score of 11.5 points (SD 3.6), second year students 12.4 (SD 3.4) and third year students 13.1 (SD 3.6). Kruskal-Wallis testing showed significant differences in feedback quality between study years (χ2(2, N=635) = 17.53, p<0.001). Dunn's post-hoc test revealed significant differences between study years one and two (p=0.012) and one and three (p<0.001). Conclusions: The developed rubric is a reliable instrument to assess narrative feedback quality. Students were able to provide feedback of sufficient quality and quality improved across study years. The instrument will allow students to assess themselves and learn where there is still room for improvement.