Prevention of VAP: role of the artificial airway, body position and setting the ventilator

Abstract

Ventilator associated pneumonia (VAP) is associated with increased morbidity, mortality and burden for the healthcare system. Oropharyngeal secretions, pooled above the endotracheal tube (ETT) cuff, are the primary source of pathogens in this iatrogenic infection. Improvements in the ETT cuff design to achieve tracheal sealing and maintaining the internal cuff pressure within the recommended range (25-30 cmH(2)O) have a pivotal role in the prevention of pulmonary aspiration of colonised oropharyngeal secretions and VAP. Additionally, ETTs coated with antimicrobial agents prevent colonisation of their internal lumen and biofilm formation; however, further evidence is necessary to assess the role of biofilm in the pathogenesis of VAP. The semirecumbent position is universally recommended; yet, laboratory studies challenge the benefits of such a position. Finally, during positive pressure ventilation, the ventilatory parameters that influence the inspiratory flow, i.e. the duty cycle, have a significant effect on retention of mucus and, potentially, on risks of lung infections. Further clinical evidence is necessary to assess benefits and limitations of ventilatory settings on VAP prevention.