Background: The insertion depth of tracheal tube differs based on sex, age, position of head and neck, type of surgery, and anatomical consideration. The aim of this study was to determine the airway related distances in Iranian patients with a non-invasive, and accurate method, the computerized reconstruction of High Resolution CT (HRCT); Virtual Bronchoscopy.
Methods: A total of 140 Iranian patients who became candidate for sinus and chest tomography, were enrolled in a cross- sectional study in Imam Khomeini Hospital Complex, Tehran, Iran, from 2006 to 2008. After reconstruction of airway related distances, Incisor- Vocal cord (IVD), Vocal cord- Carina (VCD) and Incisor- Carinal (ICD) Distances were determined.
Results: A total of 140 patients were evaluated, while 70(50%) were male. There was no statistically significant difference between age groups, sex and BMI in study patients. The measured IVD were 145.5±9.7 (males), 127.29±6.3 (females) and 136.43±12.29mm (total). For VCD, the distances were 131±13.99 (males), 122.59±11.7 (females), and 127.09±13.65mm (total). The measures for ICD in males, females, and total of patients were 277.17±16.63, 249.88±11.54, and 263.52±19.66mm respectively.
Conclusion: The insertion depth for fixation of endotracheal tube in Iranian adult patients is the same as that of anesthesia textbooks. There were no statistically significant difference between our study data and previously measured distances using invasive and less accurate methods. Virtual bronchoscopy is a noninvasive and accurate method based on reconstruction of computed tomographic images and the reconstructed images of tomography could be useful in measuring and assessment of airway anatomy.