Background and Objectives : High volume, low pressure (HVLP) cuffed tubes have been substituted for low volume, high pressure (LVHP) cuffed tubes in order to reduce complications created by the cuffed endotracheal tubes contact with the tracheal wall. Several physidans, however, prefer to use the LVHP cuff for habitual or economic reasons. Even so, careless cuff Inflation of the HVLP cuff could also induce complications. The purposes of this study were to see whether there are any differences between the usual intracuff pressure (UICP) and the Optimum intracuff pressure (OICP), to compare the OICP of three groups, and to study the correlation between the OICP and the peak inspiratory pressure (PIP) of three kinds of endotracheal tubes under mechanical Ventilation.
Methods : 82 adult patients, upon admission of the ICU, were divided into 3 groups with different cuffed tube types according to the following: Portex Profile group (n=66), HVLP cuffed tube; Portex Regular group (n=11), LVHP cuffed tube; Rusch Red group (n=5), LVHP cuffed tube. We used the Portex cuff pressure manometer for Portex Profile group, the Hewlett-Packard pressure transducer for Portex Regular, and Rusch Red group to measure the intracuff pressure (ICP). The OICP was measured with the minimal leak technique (MLT). Intracuff pressure difference (ICPD) was calculated by subtracting OICP from UICP.
Results : UICP and OICP of Portex Profile group were 33.12±22.25 ㎝H₂O, 22.02±12.5㎝H₂O, Portex Regular group, 70.09±30.88 ㎝H₂O, 69.45±30.41 ㎝H₂O and Rusch Red group, 378.40±38.60 ㎝H₂O, 337.60±74.45 ㎝H₂O. Significant difference was shown among the groups (p < 0.05). The significant difference of the PIP was not seen among the groups. Significant correlation between OICP and PIP (regression = 0.463, p < 0.01) was demonstrated only in Portex Profile group. ICPD of three groups were as high as 84 ㎝H₂O to as low as -56 ㎝H₂O. About 40% of the patients showed the allowable range.
Conclusions : This study suggests that routine check-ups of ICP are needed when the patients are admitted to the ICU. The OICP of the HVLP cuffed tube is 1/3 -1/15 of the LVHP cuffed tube. Therefore, the routine use of the HVLP tube is highiy recommended. The OICP shows positive correlation with the PIP. This suggests to make every effort to reduce the PIP.