Distance from the skin to the cervical epidural space.

BACKGROUND Cervical epidural blockade provides effective regional analgesia in clinical anesthesia and pain clinics. However, the risk for performing cervical epidural block is higher than lumber epidural anesthesia. We studied the distance from the skin to the cervical epidural space to determine whether there is any relationship between patient age, height, body weight, body mass index (BMI) and the distance from the skin to the epidural space. METHODS The study included 34 patients who underwent cervical epidural analgesic for orthopedic or plastic surgery. Cervical epidural catheterization was performed at C7-T1 intervertebral space by a midline approach with a 18-G Touhy needle. The depth of the epidural space from the skin was measured by a standard ruler. RESULTS The distance from the skin to the cervical epidural space at C7-T1 interspace was 4.81 +/- 0.81 cm (mean +/- SD). Linear regression analysis revealed significant correlation between body weight (r2 = 0.53, p < 0.0001), BMI (r2 = 0.58, p < 0.0001) and the depth of the cervical epidural space. CONCLUSIONS These results indicated that body weight and BMI could be a guideline for identification of epidural space during cervical epidural anesthesia.