Department of Orthopedics, The General Hospital of People's Liberation Army, Beijing, China.
Department of Orthopedics, Chinese PLA General Hospital and Hainan Branch, Sanya, China.
Int Wound J. 2019 Oct;16(5):1214-1221. doi: 10.1111/iwj.13197. Epub 2019 Sep 4.
The use of negative-pressure wound therapy (NPWT) has displayed significant clinical benefits in the healing of infected wounds. However, the effects of NPWT on bacterial colonisation and infection of traumatic wounds has been controversial. The aim of this study is to evaluate the impact of NPWT treatment in rabbits with a contaminated full-thickness wound on bacterial behaviour, including colony morphology, spatial distribution, fissional proliferation, and bacterial bioburden. Full-thickness wounds were created on the back of rabbits, and were inoculated with bioluminescent Staphylococcus aureus. The wounds were treated with sterile gauze dressings and NPWT with continuous negative pressure (-125 mm Hg). Wound samples were harvested on days 0 (6 hours after bacterial inoculation), 2, 4, 6, and 8 at the centre of wound beds before irrigation. Scanning electron microscopy and transmission electron microscopy (TEM) analyses were performed to determine the characteristic bacteriology. Laser scanning confocal microscopy was performed to obtain bioluminescent images, which were used to observe spatial distribution of the GFP-labelled S. aureus within the tissue and quantify the bacterial bioburden. NPWT resulted in sparse amounts of scattered bacteria on the wound surface or as sparsely spaced single colonies within the tissue. Wound bioburden on day 8 in the NPWT and gauze groups was 34.6 ± 5.5% and 141.9 ± 15.4% of the baseline values (N = 6), respectively (P < .0001). TEM showed a lack of S. aureus active fission within NPWT-treated tissue. NPWT can impact S. aureus colony morphology and spatial distribution both on the surface and within wound tissue, and reduce S. aureus as early as 48 hours after therapy initiation. Additionally, NPWT inhibits bacterial fissional proliferation in microcolonies.
负压伤口治疗（NPWT）在感染性伤口的愈合中显示出显著的临床益处。然而，NPWT 对创伤性伤口细菌定植和感染的影响一直存在争议。本研究旨在评估 NPWT 治疗对污染全层兔伤口细菌行为的影响，包括菌落形态、空间分布、分裂增殖和细菌生物负荷。在兔子背部创建全层伤口，并接种生物发光金黄色葡萄球菌。用无菌纱布敷料和持续负压（-125mmHg）对伤口进行 NPWT 治疗。在冲洗前，于第 0 天（细菌接种后 6 小时）、第 2、4、6 和 8 天，在伤口床中心采集伤口样本。进行扫描电子显微镜和透射电子显微镜（TEM）分析以确定细菌学特征。进行激光扫描共聚焦显微镜以获得生物发光图像，用于观察组织内 GFP 标记的金黄色葡萄球菌的空间分布并量化细菌生物负荷。NPWT 导致伤口表面上稀疏的散在细菌或组织内稀疏分布的单个菌落。NPWT 和纱布组第 8 天的伤口生物负荷分别为基线值的 34.6%±5.5%和 141.9%±15.4%（N=6）（P<.0001）。TEM 显示 NPWT 治疗组织内金黄色葡萄球菌无活跃分裂。NPWT 可影响表面和伤口组织内金黄色葡萄球菌的菌落形态和空间分布，并在治疗开始后 48 小时即可减少金黄色葡萄球菌。此外，NPWT 抑制微菌落中细菌的分裂增殖。
