Determining optimal cuff volume for cuffed endotracheal tubes commonly used in pediatric patients: A prospective observational study.

Objectives: To determine an optimal cuff inflation volume to achieve safe cuff pressure (20-25 cmH2O) in cuffed endotracheal tubes (ETTs) with an inner diameter of 4.5, 5.0, and 5.5 mm, which are commonly used in pediatric anaesthesia clinical practice and to create a formula to determine the optimal cuff volume.

Methods: This study was carried out between February and June 2021 in Ankara City Hospital, Ankara, Turkey. A total of 127 pediatric patients who were intubated with 4.5, 5.0 and 5.5 numbered cuffed ETTs were included in this study. The same brand of cuffed ETT was used for each patient. The diameter of the subglottic transverse airway was measured by ultrasound for selecting the appropriate tube. Cuff pressure was measured with a cuff manometer to ensure optimum cuff pressure (20-25 cmH2O).

Results: We found out that the mean ideal cuff volume inflated for 4.5 size tube was 1.7±0.3 ml, 1.9±0.3 ml for 5.0 size tube, and 2.1±0.3 ml for 5.5 size tube. Additionally we developed the "endotracheal cuff volume (ml) = 1,027 x height (m) + 0,104 x subglottic transverse diameter (mm) - 0,0191" formula to predict the most suitable inflation volume for ETT cuffs.

Conclusion: In this study, we suggested the optimal cuff volume to inflate the cuffs of ETTs 4.5, 5.0, and 5.5, which are frequently used in pediatric anaesthesia practice, in the appropriate cuff pressure range..