The effect of pre-operation ultrasonography imagingmethod on success in patients with lower level thoracalepidural procedure

Objective: It is to compare the measurement of skin epidural distance (needle length) with the depths measured by preoperative ultrasonography and computed tomography in patients with epidural anesthesia at the lower thoracic levels for thoracic and urological operations at Adnan Menderes University Practice and Research Hospital. Also to examine the correlation of these depth measurements with anthropometric values. Materials and methods: It was performed in patients who underwent epidural anesthesia in T9-10, T10-11, T11-12 spaces due to urological and thoracic surgery at Adnan Menderes University Practice and Research Hospital. The study included randomized elective surgery patients whose ASA classification between I-III and aged 18-80 years, undergoing epidural anesthesia. The neck and waist circumference of the patients were measured, BMI was calculated. The level of epidural insertion point was determined by the anesthetist and validated with USG and marked.Skin-spinous process and skin-ligamentum flavum depth were measured with USG from the same level. After the procedure, the epidural needle was marked and the value was recorded. The skin-spinous process and skin-lig.flavum distances in thoracic CT in our archive of the same patient were measured. Results: 96 patients were included in the study. The skin-lig.flavum measurement measured by USG was statistically shorter than the skin-lig.flavum measurement measured by CT and the epidural needle length for all levels (p<0,001). The distance between the skin-lig.flavum measured by CT was statistically shorter than the needle length measurement only in the T9-10 group. A correlation was found between needle length and all anthropometric data at all levels, and correlation was found between anthropometric measurements at all levels with USG and CT measurements. Conclusion: With this study, it is shown for the first time in the literature that ultrasonography, CT and anthropometric measurements may be useful to estimate the skin-epidural depth before the epidural procedure at the lower thoracic levels (T9-12).