Continuous control of tracheal cuff pressure and ventilator-associated pneumonia

Abstract

Intubation is performed in a large proportion of critically ill patients. Underinflation (< 20 cmH₂O) and overinflation (> 30 cmH₂O) of tracheal cuff were identified as risk factors for microaspiration and tracheal ischemic lesions, respectively. Maintaining cuff pressure (P_cuff) around 25 cmH₂O is recommended to prevent these complications. Periodic adjustment of P_cuff using a manual manometer might be helpful in preventing severe tracheal ischemic lesions. However, despite manual control of P_cuff, patients spend a large amount of time with underinflation of P_cuff. Two randomized controlled studies evaluated the impact of continuous control of P_cuff 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 P_cuff 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 P_cuff on VAP incidence, and to compare the different available devices.