Atraumatic Endotracheal Tube For Mechanical Ventilation [tubo Endotraqueal Atraumático Para Ventilação Mecânica.]

Background and objectives: Patients who need to stay under endotracheal intubation for long periods or when undergoing general anesthesia may develop tracheal lumen injuries due to pressure from distal cuff. In some cases, these injuries may evolve to stenosis or, occasionally, necrosis. The objective of this study was to present a modified endotracheal tube (METT) in which the cuff pressure is variable according to the cycle of mechanical ventilation (MV), which was tested on a lung simulator and animal model. Methods: Two models of endotracheal tubes, a modified (METT) and a conventional (CETT), number 7.5 mm and 8.0 mm, were connected to a lung simulator in a mechanical ventilator adjusted with two tidal volumes (TV) of 10 and 15 mL.kg -1 and a compliance of 60 mL.cmH 2O to evaluate the ventilatory efficiency of METT. Both models were also compared in Large-White pigs under general anesthesia and MV for 48 consecutive hours. Subsequently, animals were sacrificed for histopathological analysis of their tracheas. Results: Both METTs (#7.5 and 8.0) presented air leaks in lung simulator. The smallest air leak (13%) was observed in METT #7.5 with TV = 15 mL.kg -1, while the largest air leak (32%) was observed in METT #8.0 with TV = 10 mL.kg -1. Nevertheless, both METTs showed good efficiency on the lung simulator. In animals, on histopathological analysis of their tracheas, it was found that METT caused less trauma to the epithelium when compared to CETT. Conclusion: The use of a new model of ETT may decrease the risks of tracheal injury without hindering respiratory mechanics. © 2011 Elsevier Editora Ltda.613311319Sole, M.L., Penoyer, D.A., Su, X., Assessment of endotracheal cuff pressure by continuous monitoring: a pilot study (2009) Am J Crit Care, 18, pp. 133-143Bain, J.A., Late complications of tracheostomy and prolonged endotracheal intubation (1972) Int Anesthesiol Clin, 10, pp. 225-244Tornvall, S.S., Jackson, K.H., Oyanedel, E., Tracheal rupture, complication of cuffed endotracheal tube (1971) Chest, 59, pp. 237-239Cooper, J.D., Grillo, H.C., Experimental production and prevention of injury due to cuffed tracheal tubes (1969) Surg Gynecol Obstet, 129, pp. 1235-1241Bishop, M.J., Mechanisms of laryngotracheal injury following prolonged tracheal intubation (1989) Chest, 96, pp. 185-186Yang, K.L., Tracheal stenosis after a brief intubation (1995) Anesth Analg, 80, pp. 625-627McCulloch, T.M., Bishop, M.J., Complications of translaryngeal intubation (1991) Clin Chest Med, 12, pp. 507-521Magovern, G.J., Shively, J.G., Fecht, D., The clinical and experimental evaluation of a controlled-pressure intratracheal cuff (1972) J Thorac Cardiovasc Surg, 64, pp. 747-756Kamen, J.M., Wilkinson, C.J., A new low-pressure cuff for endotracheal tubes (1971) Anesthesiology, 34, pp. 482-485Arola, M.K., Anttinen, J., Post-mortem findings of tracheal injury after cuffed intubation and tracheostomy. A clinical and histopathological study (1979) Acta Anaesthesiol Scand, 23, pp. 57-68Conti, M., Pougeoise, M., Wurtz, A., Management of postintubation tracheobronchial ruptures (2006) Chest, 130, pp. 412-418Lindholm, C.E., Experience with a new orotracheal tube (1973) Acta Otolaryngol (Stockh), 75, pp. 389-390Nordin, U., Lindholm, C.E., Wolgast, M., Blood flow in the rabbit tracheal mucosa under normal conditions and under the influence of tracheal intubation (1977) Acta Anaesthesiol Scand, 21, pp. 81-94Moro, E.T., Prevenção da aspiração pulmonar do conteúdo gástrico (2004) Rev Bras Anestesiol, 54, pp. 261-275AARC (American Association for Respiratory Care) clinical practice guideline. Management of airway emergencies (1995) Respir Care, 40, pp. 749-760. , American Association for Respiratory CareBrichet, A., Verkindre, C., Dupont, J., Multidisciplinary approach to management of postintubation tracheal stenoses (1999) Eur Respir J, 13, pp. 888-893Lindholm, C.E., Prolonged endotracheal intubation (1970) Acta Anaesthesiol Scand, (SUPPL. 33), pp. 1-131Klainer, A.S., Turndorf, H., Wu, W.H., Surface alterations due to endotracheal intubation (1975) Am J Med, 58, pp. 674-683Paegle, R.D., Ayres, S.M., Davis, S., Rapid tracheal injury by cuffed airways and healing with loss of ciliated epithelium (1973) Arch Surg, 106, pp. 31-34Bryant, L.R., Trinkle, J.K., Dubilier, L., Reappraisal of tracheal injury from cuffed tracheostomy tubes. Experiments in dogs (1971) JAMA, 215, pp. 625-628Valles, J., Artigas, A., Rello, J., Continuous aspiration of subglottic secretions in preventing ventilator-associated pneumonia (1995) Ann Intern Med, 122, pp. 179-18