New issues and controversies in the prevention of ventilator-associated pneumonia

In the past 2 years, American, Canadian, and European scientific societies have published their new evidence-based guidelines for ventilator-associated pneumonia (VAP) prevention. However, these guidelines did not review some potentially useful strategies, such as the use of an endotracheal tube with an ultrathin cuff membrane, an endotracheal tube with a low-volume/low-pressure cuff, a device for continuous monitoring of the endotracheal tube cuff pressure, a device to remove biofilm from the inner site of the endotracheal tube, and saline instillation before tracheal suctioning. Only a few guidelines analyze the time of tracheostomy, and so no firm recommendations can be made regarding its importance. In addition, the guidelines diverge on the use of heat and moisture exchangers or heated humidifiers and on the use of an endotracheal tube coated with antimicrobial agents. The current review focuses on measures of VAP prevention for which there is no clear recommendation, or the use of which is controversial. A review of the literature suggests that the use of an endotracheal tube with an ultrathin and tapered-shape cuff membrane and coated in antimicrobial agents may reduce the risk of VAP. These features offer an attractive way to optimize the VAP prevention capacity of endotracheal tubes with a lumen for subglottic secretion drainage. We believe that early tracheostomy should be considered, based on the length reduction of mechanical ventilation and intensive care unit stay, reduction of mortality, and on patient comfort, although early tracheostomy has not yet been shown to favorably impact the incidence of VAP. We believed that heat and moisture exchangers should be considered based on the benefits in terms of cost savings. More research is necessary to clarify the role of continuous cuff pressure monitoring, removal of biofilm formation in the endotracheal tubes, and routine saline instillation before tracheal suctioning.