Burbank Kimberly M, Schauer Steven G, De Lorenzo Robert A, Wenke Joseph C
US Army Institute of Surgical Research.
Brooke Army Medical Center, JBSA Fort Sam Houston.
OTA Int. 2020 Oct 12;3(4):e091. doi: 10.1097/OI9.0000000000000091. eCollection 2020 Dec.
Despite meticulous surgical care and systemic antibiotics, open fracture wounds have high rates of infection leading to increased morbidity. To reduce infection rates, orthopaedic surgeons may administer local antibiotics using various carriers that may be ineffective due to poor antibiotic release from carriers, subsequent surgery to remove nondegradable carriers, and mismatch between release kinetics and material degradation. Biofilms form rapidly as bacteria that are within the wound multiply quickly and transform from the antibiotic-susceptible planktonic phenotype to the antibiotic-tolerant biofilm phenotype. This tolerance to antibiotics can occur within hours. Currently, local antibiotics are placed in the wounds using a carrier such as polymethylmethacrylate beads; however, this occurs after surgical debridement that can be hours to even a day after initial injury allowing bacteria enough time to form a biofilm that makes the antibiotic containing polymethylmethacrylate beads less effective. In contrast, emerging practices in elective surgical procedures, such as spine fusion, place antibiotic powder (e.g. vancomycin) in the wound at the time of closure. This has been shown to be extremely effective, presumably because of the very small-time period between potential contamination and local antibiotic application. There is evidence that suggests that the ineffectiveness of local antibiotic use in open fractures is primarily due to the delay in application of local antibiotics from the time of injury and propose a concept of topical antibiotic powder application in the prehospital or emergency department setting.
尽管进行了细致的手术护理并使用了全身性抗生素,但开放性骨折伤口的感染率仍然很高,导致发病率增加。为了降低感染率,骨科医生可能会使用各种载体局部应用抗生素,但由于载体对抗生素的释放不佳、后续需要手术移除不可降解的载体以及释放动力学与材料降解之间不匹配,这些方法可能无效。随着伤口内的细菌迅速繁殖并从对抗生素敏感的浮游表型转变为对抗生素耐受的生物膜表型,生物膜会迅速形成。这种对抗生素的耐受性可能在数小时内就会出现。目前,局部抗生素是使用诸如聚甲基丙烯酸甲酯珠等载体放置在伤口中的;然而,这是在手术清创后进行的,而手术清创可能在初始损伤后数小时甚至一天才进行,这使得细菌有足够的时间形成生物膜,从而使含抗生素的聚甲基丙烯酸甲酯珠效果降低。相比之下,在诸如脊柱融合等择期手术中的新兴做法是在伤口闭合时放置抗生素粉末(如万古霉素)。事实证明这非常有效,大概是因为在潜在污染和局部应用抗生素之间的时间间隔非常短。有证据表明,开放性骨折中局部使用抗生素无效主要是由于从受伤时起局部抗生素应用的延迟,并提出了在院前或急诊科环境中应用局部抗生素粉末的概念。