Objective: To evaluate the effect of body mass index and neck length on endotracheal tube movement during neck extension in thyroidectomy.
Methods: A prospective study was conducted of 30 patients undergoing thyroidectomy during an 8-month period. Patient characteristics were recorded and endotracheal tube displacement was determined.
Results: Mean body mass index was 27.8 kg/m2 (range, 17.5-34.7 kg/m2) and mean neck circumference was 43.2 cm (range, 28-56 cm). The mean (± standard deviation) upward displacement of the endotracheal tube during neck extension was 7.17 ± 5.87 mm. Patients with a larger body mass index had a significantly greater amount of tube displacement (R2 = 0.67, p < 0.0001), as did patients with a smaller neck length (R2 = 0.48, p < 0.0001).
Conclusion: Neck extension results in upward displacement of the endotracheal tube. The amount of displacement is significantly higher in patients with a larger body mass index or shorter neck length. This has particular relevance for nerve monitoring in thyroidectomy.
Keywords: Endotracheal Intubation; Recurrent Laryngeal Nerve; Thyroidectomy.