The use of antibiotics and invasive medical devices contributes to the emergence of drug-resistant microorganisms, making treatment difficult. Nosocomial pneumonia, especially that associated with mechanical ventilation, is one of the most frequent health care associated infections (HAI) in the intensive care unit (ICU). HAIs are linked to hospitalization mainly in ICUs, and are an important cause of morbidity and mortality. The microbiota of the airways in patients requiring mechanical ventilation is a serious problem because they rapidly colonize and form biofilms on the orotracheal tubes, where they persist and can contribute to the deterioration of the patient. These communities are composed of microorganisms from the normal flora of the patient as well as cross-contamination with the microbiota of the hospital environment. The most prevalent bacteria are Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumanii among others. Previous study of resistance mechanisms in planktonic state and in biofilm of K. pneumoniae from native isolates of Colombian patients, aware of the importance and the need to generate prevention strategies and alternative or new treatments specifically in infections generated around medical devices commonly used at the hospital level, this project aims to generate new knowledge and provide useful information for the outcome and prognosis of patients from microbial communities in biofilm on the orotracheal tube in two Medical-Surgical ICUs, a topic that Although it has been studied worldwide, in Colombia it would be one of the pioneers specifically in the area of ​​biofilms on invasive medical devices used routinely at the hospital level. In this prospective study, the characterization of the microbial communities of the biofilms formed on the endotracheal tube obtained by culture and by sequencing the V3-V4 region of the 16S rRNA gene was carried out in patients from 2 intensive care units in Bogotá. - Colombia in the period between December 2016 and December 2017, collecting 116 samples of orotracheal tuos, Approximately half of the samples corresponded to microorganisms belonging to the ESKAPE group, K. pneumonia was the most prevalent microorganism in the two care units intensive in the evaluation of biofilm formation and is also the one with the highest capacity for biofilm formation, followed by P. aeruginosa. The evaluation of the minimum biofilm eradication concentration (MBEC) was carried out in 4 strains (2 from each ICU) and in the plantonic state they were sensitive to carbapenemic, however in the biofilm state they increase their resistance up to 8 times. The findings presented here generate an information base on the microbiota in ICU patients that contributes to the scientific community and to future studies aimed at generating improvements in antibiotic therapy that can benefit the patient`s quality of life and reduce the burden of the disease for the health system.