Estimate the Cuff Inflation Volume to Maintain Safe Intracuff Pressure of an Endotracheal Tube

ABSTRACT

PURPOSE: The cuff of an endotracheal-tube is used to prevent air leak and pulmonary aspiration. Although high cuff pressure may result in mucosal complications, such as tracheal stenosis, endotracheal-tube cuff pressures are not routinely measured in emergency settings in Korea. We designed this study to estimate the cuff inflation volume (Vcuff) required to maintain appropriate intracuff pressure of the endotracheal tube. METHODS: We measured the cuff pressure for adult patients on whom endotracheal intubation was performed in the emergency department. The cuff pressure was measured by using a VBM(R) control inflator, and a Mallinckrodt Hi-Lo(R) endotracheal tube was used. The maximum and the minimum Vcuff were defined as Vcuff, producing a recommended maximum and minimum cuff pressure of 32 and 22 c m H2O, respectively. We performed multiple regression analysis to estimate the maximum Vcuff from age, gender, tube size, neck circumference, artificial ventilation, and peak inflation pressure. RESULTS: The maximum Vcuff was 7.1+/-1.9 ml, and the minimum Vcuff was 5.5+/-1.8 ml, with a difference of 1.6+/- 0.8 ml. The value of Vcuff in male patients were significantly higher than they were in female patients. The following regression equations for maximum Vcuff were calculated "8.2-2xfemale "for a 7.5-mm tracheal tube and "5.5+0.04 x age-1.7 x female "for a 7.0-mm tube. CONCLUSION: We have proposed equations to calculate the Vcuff for 7.5- and 7.0-mm Mallinckrodt tubes. However, this study suggests that the difference between the maximum and the minimum Vcuff is small, so the routine use of a cuff pressure gauge is required for accurate cuff pressure maintenance.