Abstract

Biofilm formation on endotracheal tubes (ETT) is an important factor in the development of ventilator-associated pneumonia (VAP). This work aimed to investigate the effectiveness of colistin (COL) against the early stages of biofilm formation by Pseudomonas aeruginosa. Two strategies were used: pre-conditioning the adhesion surfaces with COL before biofilm formation and growing biofilms in its presence. The combined effect of treating P. aeruginosa 24-hours old biofilms with Ciprofloxacin (CIP) or colistin (COL) on clean and COL-conditioned surfaces was also assessed. Random deposition of COL residues altered the physico-chemical properties of the adhesion surfaces and impaired biofilm formation. Moreover, as a consequence of the reduced amount of biofilms attached to COL conditioned surfaces, adhered cells became more exposed to the subsequent action of CIP or COL, suggesting a combined outcome of prophylactic and therapeutic COL-based strategies. Results highlighted the promising use of COL to prevent the establishment of biofilms on ETT.

摘要

气管导管 (ETT) 上的生物膜形成是呼吸机相关性肺炎 (VAP) 发展的重要因素。这项工作旨在研究粘菌素 (COL) 对铜绿假单胞菌生物膜形成早期阶段的有效性。使用了两种策略：在生物膜形成之前用 COL 对粘附表面进行预处理，并在其存在下生长生物膜。治疗铜绿假单胞菌的综合作用还评估了在清洁和经 COL 调节的表面上使用环丙沙星 (CIP) 或粘菌素 (COL) 的 24 小时生物膜。COL 残留物的随机沉积改变了粘附表面的物理化学性质并损害了生物膜的形成。此外，由于附着在 COL 条件表面上的生物膜数量减少，粘附的细胞变得更多地暴露于 CIP 或 COL 的后续作用，这表明基于 COL 的预防性和治疗性策略的综合结果。结果强调了使用 COL 来防止在 ETT 上建立生物膜的前景。