C. Prada, S. Bzovsky, B. Petrisor, M. Bhandari, S. Sprague, Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, Ontario, Canada.
S. L. Tanner, K. Jeray, Department of Orthopaedic Surgery, Prisma Health-Upstate, Greenville, SC, USA.
Clin Orthop Relat Res. 2020 Dec;478(12):2846-2855. doi: 10.1097/CORR.0000000000001293.
Although many studies report the incidence and prevalence of surgical site infections (SSIs) after open fractures, there is limited information on the treatment and subsequent outcomes of superficial SSIs in patients with open fractures. Additionally, clinical studies describing the factors that are associated with persistent infection after nonoperative treatment with antibiotics for patients with superficial SSIs are lacking.
QUESTIONS/PURPOSES: Therefore, we asked: (1) What proportion of patients with superficial SSIs after open fracture treatment developed persistent infection after nonoperative treatment (that is, treatment with antibiotics alone)? (2) What risk factors are associated with SSIs that do not resolve with nonoperative (antibiotic) treatment? As a secondary objective, we planned to analyze the microbiological information about participants wound cultures, when these were available, and the proportion of positive cultures for patients whose SSIs were not resolved by antibiotics alone.
This is a secondary analysis of the Fluid Lavage of Open Wounds (FLOW) trial dataset. The FLOW trial included 2445 patients with operatively managed open fractures. FLOW participants who had a nonoperatively managed superficial SSI diagnosed in the 12 months post-fracture were included in this analysis. Superficial SSIs were diagnosed in 168 participants within 12 months of their fracture. Of these, 83% (139) had their superficial SSI treated with antibiotics alone. Participants were grouped into two categories: (1) 97 participants whose treatment with antibiotics alone resolved the superficial SSI and (2) 42 participants whose treatment with antibiotics alone did not resolve the SSI (defined as undergoing surgical management or the SSI being unresolved at latest follow-up [12-months post-fracture for the FLOW trial]). Of the participants whose treatment with antibiotics alone resolved the SSI, 92% (89 of 97) had complete follow-up, 6% (6 of 97) were lost to follow-up before 12 months, 1% (1 of 97) withdrew consent from the study before 12 months, and 1% (1 of 97) experienced mortality before 12 months. Of the participants whose treatment with antibiotics alone did not resolve the SSI, 90% (38 of 42) had complete follow-up, 7% (3 of 42) were lost to follow-up before 12 months, and 2% (1 of 42) withdrew consent from the study before 12 months. A logistic binary regression analysis was conducted to identify factors associated with persistent infection despite superficial SSI antibiotic treatment. Based on biologic rationale and previous evidence, we identified a priori 13 potential factors (corresponding to 14 levels) to be included in the regression model.
The antibiotic treatment resolved the superficial SSI in 70% (97 of 139) of patients and did not resolve the SSI in 30% (42 of 139). After controlling for potential confounding variables, such as age, fracture severity, and time from injury to initial surgical irrigation and débridement, superficial SSIs diagnosed later in follow-up were associated with antibiotics not resolving the SSI (odds ratio 1.05 [95% CI 1.004 to 1.009] for every week of follow-up; p = 0.03). Sex, fracture pattern, and wound size were not associated with antibiotics not resolving the SSI.
Our secondary analysis of prospectively collected FLOW data suggests that antibiotics alone can be an appropriate treatment option when treating superficial SSIs after an open fracture wound, especially when promptly diagnosed. Further research with longer follow-up time is needed to better identify the natural history of superficial SSIs and possibly some dormant or subclinical infections to help clinicians in the treatment decision-making process.
Level III, therapeutic study.
尽管许多研究报告了开放性骨折后手术部位感染（SSI）的发生率和流行率，但关于开放性骨折患者浅表性 SSI 的治疗和后续结果的信息有限。此外，缺乏描述抗生素非手术治疗浅表性 SSI 患者持续性感染相关因素的临床研究。
问题/目的：因此，我们提出了以下问题：（1）开放性骨折治疗后发生浅表性 SSI 的患者中，有多少比例在接受非手术治疗（即单独使用抗生素治疗）后发生持续性感染？（2）哪些危险因素与非手术（抗生素）治疗后无法解决的 SSI 相关？作为次要目标，我们计划分析参与者伤口培养物的微生物学信息，当这些信息可用时，以及抗生素单独治疗无法解决 SSI 的患者的阳性培养物比例。
这是 Fluid Lavage of Open Wounds（FLOW）试验数据集的二次分析。FLOW 试验纳入了 2445 例接受手术治疗的开放性骨折患者。在骨折后 12 个月内诊断为非手术治疗的浅表性 SSI 的 FLOW 参与者被纳入本分析。在骨折后 12 个月内，168 名参与者被诊断为浅表性 SSI。其中，83%（139 名）接受单独使用抗生素治疗浅表性 SSI。参与者分为两组：（1）97 名参与者单独使用抗生素治疗后浅表性 SSI 得到解决，（2）42 名参与者单独使用抗生素治疗后 SSI 未得到解决（定义为接受手术治疗或 SSI 在最晚随访时未得到解决[FLOW 试验为骨折后 12 个月]）。在单独使用抗生素治疗后 SSI 得到解决的参与者中，92%（89/97）完成了随访，6%（6/97）在 12 个月前失访，1%（1/97）在 12 个月前退出研究，1%（1/97）在 12 个月前死亡。在单独使用抗生素治疗后 SSI 未得到解决的参与者中，90%（38/42）完成了随访，7%（3/42）在 12 个月前失访，2%（1/42）在 12 个月前退出研究。我们进行了逻辑二元回归分析，以确定尽管对浅表性 SSI 进行了抗生素治疗但仍存在持续性感染的相关因素。基于生物学原理和先前的证据，我们确定了 13 个潜在因素（对应 14 个水平）预先纳入回归模型。
抗生素治疗在 70%（97/139）的患者中解决了浅表性 SSI，在 30%（42/139）的患者中未解决 SSI。在控制年龄、骨折严重程度和从受伤到初始冲洗和清创的时间等潜在混杂变量后，在随访后期诊断的浅表性 SSI 与抗生素无法解决 SSI 相关（每增加一周随访，优势比为 1.05[95%CI 1.004 至 1.009]；p=0.03）。性别、骨折模式和伤口大小与抗生素无法解决 SSI 无关。
我们对前瞻性收集的 FLOW 数据的二次分析表明，当治疗开放性骨折伤口的浅表性 SSI 时，单独使用抗生素可能是一种合适的治疗选择，尤其是在及时诊断的情况下。需要进行更长时间随访的进一步研究，以更好地了解浅表性 SSI 的自然病史，并可能发现一些休眠或亚临床感染，以帮助临床医生在治疗决策过程中做出决策。
III 级，治疗性研究。
