The spinal block involves placement of a local anesthetic in the subdural or subarachnoid space, which lies inside the dura, the spinal cord covering. This differs from the epidural block, in which the anesthetic is placed outside the spinal cord covering (in the epidural space). Spinal blocks are rarely used during labor because they tend to suppress motor function and only work for a limited period of time. However, they can be used during the second stage of labor, just prior to delivery, in cases where complete anesthesia of the pelvis is needed without delay. This type of spinal block is referred to as a saddle block because it provides anesthesia to only the pelvis and perineum (area between the vagina and anus). In some situations, such as an emergency cesarean section in the second stage of labor, a saddle block may be better than an epidural block because it is quicker and easier to place. Spinal blocks may also be used in patients with planned cesarean sections. Leaking of spinal fluid and subsequent spinal headaches can be avoided by using an extremely small needle (pencil-point needle) to administer the medication into the subdural space.
Spinal Anesthesia During Delivery
Medically Reviewed by Douglas Levine, Gynecology Service/Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY on March 15, 2012 — Written by the Healthline Editorial Team