Division of Gastroenterology, Brigham and Women's Hospital, 75 Francis St., Boston, MA 02115, USA.
Dig Dis Sci. 2012 Aug;57(8):2130-6. doi: 10.1007/s10620-012-2126-3. Epub 2012 Mar 24.
NOTES via the gastrointestinal tract raises the specter of intra-peritoneal infection. Various anti-microbial techniques have been employed in animal and human survival studies, including saline lavage, intravenous and topical antibiotics, and povidone-iodine, although there is a paucity of data regarding their general effectiveness.
To assess the effectiveness of existing sterilization techniques for NOTES by quantifying and speciating colony-forming units (CFUs) before and after treatment.
Ex vivo animal studies; bacteriological study.
Stomachs and distal colons were harvested en bloc from ten fasted adult white pigs following euthanasia. Half received cefazolin 1 g intravenously prior to killing. Multiple tissue samples were obtained from each resected organ. Each tissue sample was then assigned to one of five treatment arms: (1) normal saline, (2) Betadine, (3) cefazolin/metronidazole suspension, (4) chlorhexidine, (5) no treatment. Fifteen samples were used per arm. After treatment, the mucosal surface of each sample was swabbed and inoculated in normal saline, followed by serial dilutions, which were then plated onto sheep's blood agar plates and incubated under aerobic and anaerobic conditions. CFUs were quantified and speciated.
Median bacterial density was estimated to be 8.0 × 10(5) CFUs/ml (stomach) and 1.9 × 10(6) CFUs/ml (colon). The predominant organisms were Escherichia coli (stomach) and both E. coli and Enterococcus sp. (colon). Saline and antibiotic suspension lavages caused a 1-log reduction in stomach and colon. Betadine/chlorhexidine lavage resulted in a 4-log reduction. Intravenous antibiotics alone resulted in a 4-log reduction. Combining intravenous antibiotics and either Betadine or chlorhexidine decreased counts to the 10(1) level. By Kruskal-Wallis method, differences were statistically significant (p = 0.001).
The use of intravenous antibiotics in addition to topical Betadine or chlorhexidine effectively reduced microbial burden in both gastric and colonic mucosa in this porcine model to the 10(1) level.
经胃肠道NOTES 会引起腹腔内感染的担忧。在动物和人类生存研究中，已经采用了各种抗菌技术，包括生理盐水灌洗、静脉内和局部应用抗生素以及聚维酮碘，尽管关于它们的总体有效性的数据很少。
通过在治疗前后量化和鉴定集落形成单位 (CFU) 来评估NOTES 中现有灭菌技术的有效性。
离体动物研究；细菌学研究。
在安乐死后，从 10 只禁食成年白猪中整块采集胃和远端结肠。一半在处死前静脉内给予头孢唑林 1g。从每个切除的器官中获取多个组织样本。然后将每个组织样本分配到以下五个治疗组之一：（1）生理盐水，（2）Betadine，（3）头孢唑林/甲硝唑混悬液，（4）洗必泰，（5）无处理。每个组使用 15 个样本。治疗后，用拭子擦拭每个样本的黏膜表面并接种于生理盐水，然后进行连续稀释，再将其接种于绵羊血琼脂平板，并在需氧和厌氧条件下孵育。定量并鉴定 CFU。
中位细菌密度估计为胃 8.0×10(5)CFU/ml 和结肠 1.9×10(6)CFU/ml。主要病原体为大肠埃希菌（胃）和大肠埃希菌和肠球菌属（结肠）。生理盐水和抗生素混悬液灌洗可使胃和结肠的细菌数量减少 1 个对数级。洗必泰/氯己定灌洗可使细菌数量减少 4 个对数级。单独静脉内给予抗生素可使细菌数量减少 4 个对数级。静脉内给予抗生素并联合使用洗必泰或氯己定可将细菌计数减少至 10(1)水平。采用 Kruskal-Wallis 方法，差异具有统计学意义（p = 0.001）。
在本猪模型中，静脉内给予抗生素联合局部使用洗必泰或氯己定可有效将胃和结肠黏膜的微生物负荷减少至 10(1)水平。
