comparison of prophylactic effects of polyurethane cylindrical or tapered cuff and polyvinyl chloride cuff endotracheal tubes on ventilator-associated pneumonia.

because microaspiration of contaminated supraglottic secretions past the endotracheal tube cuff is considered to be central in the pathogenesis of pneumonia, improved design of tracheal tubes with new cuff material and shape have reduced the size and number of folds, which together with the addition of suction ports above the cuff to drain pooled subglottic secretions leads to reduced aspiration of oropharyngeal secretions. so we conducted a study to compare the prophylactic effects of polyurethane-cylindrical or tapered cuff and polyvinyl chloride cuff endotracheal tubes (ett) on ventilator-associated pneumonia. this randomized clinical trial was carried out in a 12 bed surgical intensive care unit. 96 patients expected to require mechanical ventilation more than 96 hours were randomly allocated to one of three following groups: polyvinyl chloride cuff (pcv) ett, polyurethane (pu) cylindrical sealguard ett and pu taperguard ett. cuff pressure monitored every three hours 3 days in all patients. mean cuff pressure didn't have significant difference between three groups during 72 hours. pneumonia was seen in 11 patients (34%) in group pvc, 8 (25%) in sealguard and 7 (21%) in taperguard group. changes in mean cuff pressure between sealguard and pvc tubes and also between taperguard and pvc tubes did not show any significant difference. there was no significant difference in overinflation between three groups. the use of ett with pu material results in reducing ventilator-associated pneumonia compared to ett with pvc cuff. in pu tubes taperguard has less incidence of ventilator-associated pneumonia compared to sealguard tubes.