Continuous control of tracheal cuff pressure and ventilator-associated pneumonia

Intubation is performed in a large proportion of critically ill patients. Underinflation (< 20 cmH(2)O) and overinflation (> 30 cmH(2)O) of tracheal cuff were identified as risk factors for microaspiration and tracheal ischemic lesions, respectively. Maintaining cuff pressure (Pcuff) around 25 cmH(2)O is recommended to prevent these complications. Periodic adjustment of Pcuff using a manual manometer might be helpful in preventing severe tracheal ischemic lesions. However, despite manual control of Pcuff, patients spend a large amount of time with underinflation of Pcuff. Two randomized controlled studies evaluated the impact of continuous control of Pcuff on microaspiration of gastric contents and ventilation-acquired pneumonia (VAP) incidence. The first study using an electronic device failed to demonstrate any impact of continuous control of Pcuff on VAP rate (15% in the two groups). However, the second one found the pneumatic device to be associated with significantly reduced microaspiration of gastric contents, tracheobronchial colonization, and VAP rate (9.8% vs. 26.2%, p = 0.032, odds ratio [95% confidence interval] 0.30 [0.11-0.84]). Different devices and different patient characteristics might explain the different results found in these studies. Further randomized controlled multicenter trials are needed to determine the impact of continuous control of Pcuff on VAP incidence, and to compare the different available devices.