The Effect of Airway Pressure on the Inspiratory and Expiratory Intracuff Pressure

Abstract

In high volume low pressure cuffs, the elastic forces are very low and when inflated and in contact with the tracheal wall they are not fully distended. Theoretically under these circumstances any increase in volume can cause only a small increase in intracuff pressure1) But, in intensive care unit clinically we have experienced the rising of intracuff pressure when airway pressure went up in the same patients. In this study we attemped to observe the effect of the change of airway pressure (mean airway pressure, peak airway pressure) on the intracuff pressure during inspiration and expiration in 50 intensive care unit patients who were intubated and mechanically ventilated. The results are as follows: 1) The optimum cuff pressure of inspiration(OPE) was 23.48±13.0495~60)cmH2O and optimum cuff pressure of expiration(OPE) was 16.82±11.62(4~2)cmH2O. 2) The peak inspiratory pressure was 32.24±11.49(13.0~64.6)cmH2O and mean airway pressure was 12.23 6.67(3.7~38.0)cmH2O. 3) The optimum cuff pressure of inspiration was highly correlated with peak inspiratory pressure by multiple regression analysis(R²=0.701, p=0.000).