Department of Orthopaedic Surgery & Biomedical Engineering, University of Tennessee-Campbell Clinic, Memphis TN.
Division of Epidemiology, Biostatistics, and Environmental Health, School of Public Health, University of Memphis, Memphis TN.
J Orthop Trauma. 2018 Jul;32(7):322-326. doi: 10.1097/BOT.0000000000001171.
To determine the frequency and effect of under-dosing prophylactic weight-based antibiotics in patients with open tibial fractures. We hypothesized that patients who did not receive appropriate weight-based dosing of prophylactic antibiotics would have higher rates of infection.
Retrospective cohort study.
Level 1 Trauma Center.
PATIENTS/PARTICIPANTS: Patients 18 years of age or older with high-grade (Gustilo-Anderson type IIIA or IIIB) open extraarticular tibial fractures over a 5-year period.
The primary outcome was deep infection within one year of initial injury. Appropriate weight-based dosing of cefazolin was defined as: at least 1 g for patients <80 kg, 2 g for patients between 80 and 120 kg, and 3 g for patients >120 kg.
Sixty-three patients met the inclusion criteria; 21 (33%) were under-dosed with cefazolin at the time of initial presentation. Among the 20 patients who subsequently developed deep infection, only 55% were appropriately dosed with cefazolin; of the patients who did not develop deep infection, 72% were appropriately dosed with cefazolin (P = 0.18). Univariate analysis revealed that hypertension was associated with infection (P = 0.049). Multivariable logistic regression analysis of infection due to all organisms did not reveal a statistically significant reduction in the odds of infection with appropriate weight-based dosing of cefazolin [Odds ratio = 0.42 (95% confidence interval, 0.12-1.48), P = 0.177]. Five of 7 (71%) of the gram positive, non-methicillin-resistant Staphylococcus aureus, infections occurred in patients who were under-dosed with cefazolin. Five (23.8%) of 21 patients who were under-dosed with cefazolin had gram-positive, non-methicillin-resistant S. aureus infections, compared to 2 (4.8%) of 42 patients who were appropriately dosed (P = 0.036).
Under-dosing of weight-based antibiotics in the treatment of open fractures is common. Appropriate weight-based dosing of cefazolin for prophylaxis in high-grade open tibial fractures reduces the frequency of infection due to cefazolin-sensitive organisms. Interestingly, organisms not susceptible to cefazolin were responsible for the majority of infections. The effect of under-dosing of cefazolin and other weight-based antibiotics deserves further investigation in larger studies.
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
确定开放性胫骨骨折患者预防性基于体重的抗生素剂量不足的频率和影响。我们假设未接受适当基于体重的预防性抗生素剂量的患者感染率会更高。
回顾性队列研究。
1 级创伤中心。
患者/参与者：5 年内，18 岁及以上的高分级（Gustilo-Anderson 型 IIIA 或 IIIB）开放性关节外胫骨骨折患者。
主要结局是初始损伤后 1 年内深部感染。头孢唑林的适当基于体重剂量定义为：<80kg 的患者至少 1g，80-120kg 的患者 2g，>120kg 的患者 3g。
63 名患者符合纳入标准；21 名（33%）在初次就诊时头孢唑林剂量不足。在随后发生深部感染的 20 名患者中，仅有 55%的患者接受了头孢唑林的适当剂量；未发生深部感染的患者中，72%接受了头孢唑林的适当剂量（P=0.18）。单变量分析显示，高血压与感染相关（P=0.049）。对所有病原体感染的多变量逻辑回归分析并未显示头孢唑林适当基于体重剂量可显著降低感染的可能性[优势比=0.42（95%置信区间，0.12-1.48），P=0.177]。7 株（71%）革兰阳性、非耐甲氧西林金黄色葡萄球菌感染发生在头孢唑林剂量不足的 5 名患者中。21 名头孢唑林剂量不足的患者中有 5 名（23.8%）发生革兰阳性、非耐甲氧西林金黄色葡萄球菌感染，而 42 名剂量适当的患者中有 2 名（4.8%）发生感染（P=0.036）。
开放性骨折治疗中基于体重的抗生素剂量不足很常见。在高分级开放性胫骨骨折中预防性使用头孢唑林进行适当基于体重的剂量可降低头孢唑林敏感菌引起的感染频率。有趣的是，对头孢唑林不敏感的病原体是导致大多数感染的原因。头孢唑林和其他基于体重的抗生素剂量不足的影响值得在更大规模的研究中进一步探讨。
治疗学 3 级。有关证据水平的完整描述，请参见作者指南。
