A Clinical Measurement of the Distance from the Skin to the High Thoracic Epidural Space in Women

Chung, Min Gue; Ok, Si Young; Kim, Soon Im; Kim, Sun Chong

Abstract

BACKGROUND: Segmental high thoracic epidural anesthesia and analgesia is now accepted as a popular technique for thoracic and breast surgeries, as well as post operative pain relief. However, a high thoracic epidural puncture is technically difficult, which can cause neurological complications. Having prior knowledge of the distance from the skin to the thoracic epidural space may be helpful for the prevention of complications during this procedure. This study was undertaken to evaluate the distance from the skin to the thoracic epidural space and the insertion angle of the Tuohy needle, as measured using a protractor, and to determine any potential relationship between a patient's height, weight and BMI (body mass index) with the calculated distance on the preoperative chest CT and the distance from the skin to the epidural space in 50 women undergoing a mastectomy.
METHODS
In the sitting position, using a mid-line approach, the T4-5 epidural depth was measured in 50 mastectomy patients after the block had been successfully confirmed. The patient's age, height, weight and BMI, as well as the calculated distance on the preoperative chest CT were then checked.
RESULTS
The distance from the skin to the thoracic epidural space at the T4-5 intervertebral level and insertion angle were 5.59 +/- 1.26 cm and 54.40 +/- 12.12 degrees, respectively. A significant correlation was found between the epidural depth and, the weight, BMI and calculated distance on the preoperative chest CT.
CONCLUSIONS
The distance from the skin to the thoracic epidural space showed significant relationships with the weight, BMI and calculated distance on the preoperative chest CT.