Flovent Inhaler

- High-volume, Low-pressure Cuffs (10)

The absolute intracuff pressures reported in this study are estimates and are subject to error; however, the fact that cuff inflation pressure must be increased in order to seal the trachea against high PIPs is clear. Nonetheless, it is not generally appreciated that current high-volume, low-pressure cuff designs cannot effectively seal the trachea with low pressures when the PIP is high. The problem does not revolve around improper cuff inflation techniques but is instead an inherent limitation of cuff design as outlined in the next two sections.
Self-Sealing Action
When sealing the trachea during positive pressure ventilation, the ETT cuff is suspended between atmospheric pressure on one side and airway pressure on the other. The cuff resists leakage of gas from the airway by pressing itself outward into the tracheal mucosa (the CT pressure). Because the CT pressure is equal to the intracuff pressure in large diameter cuffs, a leak can develop whenever airway pressure exceeds intracuff pressure. However, our experiment showed that in such cuffs intracuff pressure begins to rise as the airway pressure exceeds the baseline cuff inflation pressure (Fig 3).

June 17, 2013 Cardiac function
Tags: airway pressure ischemic tracheal complications tracheal stenosis