Do pediatric patients undergoing cardiac surgeries require larger-size cuffed endotracheal tubes? A prospective study

Abstract

Background: There is a controversy over using either smaller- or larger-size endotracheal tubes (ETT) in children undergoing cardiac surgery, and some anesthesiologists prefer to use ETT sizes different from the formula-based sizes. The aim of the present study was to compare proper-size cuffed ETT in children undergoing cardiac vs noncardiac surgeries.

Methods: In an observational prospective study, 80 children planned to undergo noncardiac elective surgeries (NCS group) and 80 children scheduled for cardiac surgeries (CS group) were recruited. For intubation, initial cuffed ETT size was calculated based on the following formula: Tube size (mm ID) = age (year)/4 + 3.5. The estimated ETT size for each age group and the size of final utilized tubes for each age range were recorded.

Results: Patients of tube sizes 4.5, 5, and 5.5 in the CS group were of lower age, weight, height, and body surface area compared with the patients of the same tube sizes in the NCS group (P < 0.05). The compatibility of the predicted vs actual required tube sizes was more in the NCS group compared to the CS group (72.5% vs. 56.2%; P = 0.02). Additionally, the cases with underestimated tube sizes were significantly more in the CS group compared with the NCS group (38.8% vs. 18.8%, P = 0.01).

Conclusion: Children undergoing cardiac surgeries in relation to their age and body size do require larger-size ETTs compared with the children scheduled for noncardiac surgeries.