بررسي فاصله پوست تا فضاي ساب آراكنوييد در بي حسي اسپاينال

Evaluatio of the Distance from the skin to the subarachnoid space in spinal anesthesia

Background and purpose: Spinal anesthesia is one of the most common techniques in general surgery. We studied the distance from skin to spine to determine whether there is any relationship between patients age, body mass index (BMI), weight and the distance from the skin to the spine. The measurement of the distance from skin to the spine is not as well preformed as the distance from skin to the epidural. Materials and methods: In this prospective observational study, general and orthopedic surgery in Jun 2001-March 2003 were included. Spinal anesthesia was performed at L3-L4 space in sitting position. The distance from the skin to subarachnoid with theneedle was advanced until free flow of cerebrospinal fluid was observed. The siatance form the skin to the subarachnoid after injection of lidocaine was measured by a standard ruler. Results: The distance from the skin to the subarachnoid space was 45.2 ± 4.8 mm (mean ± SD). Linear regression analysis revealed a significant correlation between the distance from the skin to the subarachnoid space body weight (r=0.389, p=0.000), BMI (r=0.298, p=0.002) but a nonsignificant correlation with height (p-0.09, r-0.098). Conclusion: These results indicated that body weight and BMI could be a guidline for identification of subarachnoid space during spinal anesthesia in sitting position.