【作者】 杨勇；

【导师】 鲁晓波；

【作者基本信息】 泸州医学院 ， 外科学， 2010， 硕士

【摘要】 目的：探讨一种实用、有效、副作用少的具有自身预防感染的外固定螺钉,并通过致病菌污染动物模型感染预防实验进行比较分析,论证此方法的可行性和优越性,以及可能的抗菌机理,为后期临床应用提供了客观依据与理论支持。方法：1.材料：不锈钢外固定螺钉、HA粉末、FumatT200-4抗菌粉体、金黄色葡萄球菌悬液(ATCC 25923标准菌株),实验动物为健康新西兰大白兔,3-6个月龄。2.抑菌试验及动物预防感染实验标本分组：实验组：载银羟基磷灰石涂层外固定螺钉组,对照组：不锈钢外固定螺钉组3.实验模型制备：将95wt%羟基磷灰石粉末与5wt%FumatT200-4抗菌粉体混合,应用真空等离子喷涂设备对不锈钢外固定螺钉行等离子喷涂。实验组对照组外固定针予以消毒处理备用,健康新西兰大耳大白兔,共24只制作污染模型,平均体重2.32±0.06Kg,雌性13只,雄性11只,按随机排列表法随机分为2组,每组12只,大白兔予氯胺酮50mg/kg行肌肉麻醉。分别置入不锈钢外固定螺钉及载银羟基磷灰石涂层外固定螺钉,后注入金黄色葡萄球菌悬液。普通食养环境食养。比较两种外固定螺钉对兔外固定针道金葡菌污染模型的预防作用。4.标本采集和资料收集方法：术后第1、3、7天，14、28天测量兔体温、体重,留取血液标本,进行血常规、C反应蛋白检测。术后第1、3、7、14、28天取针道周围组织进行病理学检查。组织进行细菌普通培养。结果1.24只股骨置入外固定针并制备金葡菌污染模型兔。实验过程中发生兔死亡补足24只。最后共26只完成实验,每组12只,雌性15只,雄性11只。2.实验组感染2只,对照组感染对照组11只,实验组与对照组感染率有明显区别(P<0.05)。3.实验组和对照组大白兔的体重在术后第1、3、7、14和28天比较(P>0.05),差异无统计学意义。4.实验组和对照组大白兔的肛温在术后第1、3、7、14和28天比较(P>0.05),差异无统计学意义。5.实验组大白兔的静脉血白细胞计数和CRP含量在术后第3、7、14天均明显低于对照组(P<0.05),差异有统计学意义。但是在术后第1天和第28天,两组之间对照(P<0.05)差异无统计学意义。发生感染的大白兔部分脓肿形成,周围皮肤红肿,部分伴有脓液外溢。外固定钢针周围有黄白色脓液附着,周围部分坏死组织。感染大白兔取分泌物、脓液行细菌培养,均培养出金葡菌。外固定针周围组织病理学检查(HE染色)可见：发生感染的大白兔外固定针周围组织有坏死,大量中性粒细胞、淋巴细胞、单核细胞聚集。后期见纤维组织增生和炎性坏死病灶并存。结论载银羟基磷灰石涂层外固定针可以有效预防兔外固定针道金黄色葡萄球菌污染模型发生感染。为下一步过渡到临床应用提供充分的实践依据。更多还原

【Abstract】 Abstract:Objective:To explore external fixation pins that is effective, practical, less side effects, prevention of infection with itself, and demonstrate the feasibility, superiority and the possible antibacterial mechanism of this method through the animals experiment that compared infection rate, which can provide an objective basis and theoretical support for late-stage clinical application. Method:1. Materials:Stainless steel external fixation pins、HA powder、FumatT200-4 anti-bacterial powder、Suspension of Staphylococcus aureus (ATCC 25923 Standard Strain), New Zealand white rabbits as experimental animals, healthy 3-6 months old.2. Antimicrobial testing and prevention of infection in animal samples were sub-groups:the experimental group containing silver screw fixation of hydroxyapatite coated and control groups of stainless steel screw fixation group.3. Preparation of experimental model:Take 95wt% of hydroxyapatite powder and 5wt% FumatT200-4 anti-bacterial powder mixed, and stainless steel fixation screws for plasma sprayed. Control groups were to be disinfected with external fixation pin spare, rabbits made a total of 24 pollution model, the average weight of 2.32±0.06Kg, female 11, male 13, a list of random row were randomly divided into 2 groups,12 in each group, rabbits were anesthetized for ketamine 50mg/kg line muscle. Fixation pins were placed in femur, Staphylococcus aureus suspension was injected into the pin tract. Compared effect of infection prevention between two kinds of fixation pin hole on the rabbit model of S. aureus.4. Specimen collection and data collection techniques:measured of rabbit body temperature, body weight daily. Phlebotomize blood samples for blood, C-reactive protein test on1,3,7,14,28 days after operation. Take soft tissue surrounding pin tract for pathological examination and bacteria culture on 1,3,7,14,28 days after surgery. Results 1.24 external fixation pins placed in femur and raised rabbit model of Staphylococcus aureus contamination. Rabbit died during the experiment, make up 24,26 completed the final test, female 15, and male 11.2. Two rabbits infected in experimental group, the control group infected 11.Infection rates between experimental group and control group are significantly different (P<0.05).3. Compared body weight of rabbits between experimental group and control group in 1,3,7,14 and 28 days after surgery (P> 0.05), the difference was not statistically significant.4. Compared rectal temperature of rabbits between experimental group and control group at 1,3,7,14 and 28 days after surgery compared (P> 0.05), the difference was not statistically significant. 5. Experimental rabbits the blood leukocyte count and CRP levels were significantly lower than the control group in 3,7,14 days (P<0.05), the difference was statistically significant. However, (P>0.05) difference was not statistically significant between the two groups control on 1 and 28 days after surgery. The rabbits that were infected had abscess in the incision, skin irritation surrounding, some associated with sinus formation and pus spills. External fixation pin cohered around the yellow-white pus and some necrotic tissue. Secretions of infected rabbits were taken pus bacterial culture, S. aureus was cultured. Histopathologic examination of soft tissue that around external fixation pin (HE stain) shows:there are necrotic tissues, a large number of neutrophils, lymphocytes, monocots, plasma cells. Fibrosis and inflammatory necrosis lesions coexist the late. Conclusion external fixation pins of Ag-HA coating can be effective in preventing pin tract infection in rabbit model which infected by Staphylococcus aureus. And provide adequate practical basis for clinical applications.更多还原