Is Montgomery tracheal Safe-T-Tube clinical failure induced by biofilm?

OBJECTIVES: Montgomery Safe-T-Tube deterioration and early biofilm colonization may explain the discomfort claimed by many patients and clinical failures. The aim of the study was to analyze the deterioration of Montgomery Safe-T-Tube morphological and mechanical properties in vivo in 16 patients by using microbiological methods, optical and electron microscopy, and engineering tests. STUDY DESIGN: Prospective controlled study at a single medical center. SETTING: University hospital. SUBJECTS AND METHODS: The study, conducted from April 2007 to February 2012 at the "Sapienza" University of Rome, was designed to collect 2 Montgomery Safe-T-Tubes from each patient. The first was removed 3 to 15 days after insertion (group A) and the second at least 90 days after (group B). Specimens underwent microbiologic assays, electron microscopic analysis, immunocytologic analysis, and mechanical tests. RESULTS: Microorganisms were not isolated in 2 group A cases (12%), whereas they were in all group B cases. Biofilm was identified in 11 of 16 (69%) group A samples and in 16 of 16 (100%) group B samples (P = .0149) using scanning electron microscopy. Immunohistochemistry showed monocyte-granulocyte line cells producing interleukin-1ß on the external surfaces of Montgomery Safe-T-Tubes. The tensile test showed that the wear related to the longer period of use makes Montgomery Safe-T-Tubes more rigid than newer ones. CONCLUSION: Early biofilm colonization takes place in Montgomery Safe-T-Tubes in most cases. The mechanical decay could be justified in part by the destructive biofilm activity and by the release of inflammatory effectors and enzymes.