Comparison of Tracheal Diameter Measurements on Radiograph Versus Computed Tomography at a Tertiary Care Hospital in Pune, Central India

Background Variations in tracheal diameter with respect to factors like age and gender are one of the major factors affecting the size of the endotracheal tube (ETT) preferred in a patient. It is important to pre-determine this figure because a tube of a larger size predisposes the patient for tracheal mucosal ischemia, while one of a smaller size may not ensure adequate oxygen saturation in the patient. Purpose We undertook this study to assess the accuracy of radiograph versus computed tomography (CT) and comment on whether a CT should be carried out mandatorily in all patients where intubation is needed. Materials and methods The study was undertaken at Dr DY Patil Medical College, Hospital, and Research Center, a tertiary care institute in Pune, India. A total of 217 patients in whom both chest radiograph and chest CT were performed were enrolled in the study and measurements were performed at suitable landmarks which correspond to the position of endotracheal tubes. Results The males had a mean age of 44.2 years and females of 41.7 years. The mean X-ray transverse diameter was 15.4 ± 3.2 (SD) mm, mean CT axial transverse diameter was 15.3 ± 3.4 (SD) mm, mean CT sagittal diameter was 14.8 ± 3.7 (SD) mm, and the mean CT coronal diameter was 15.2 ± 3.5(SD)mm. Conclusions There was a significant difference in mean X-ray transverse diameter (Low kV), CT axial transverse diameter, CT sagittal diameter, and CT coronal diameter between males and females. Mean values were significantly higher in males as compared to females. There was a significant difference in tracheal diameters for different age groups, irrespective of the modality. Bland-Altman analysis revealed no significant difference between chest radiograph and CT for tracheal diameter measurement.