Spinal Anesthesia

Excerpt

The development of regional anesthesia started with the isolation of local anesthetics, the first being cocaine (the only naturally occurring local anesthetic). The first regional anesthetic technique performed was spinal anesthesia, and the first operation under spinal anesthesia was in 1898 in Germany by August Bier. Before this, the only local anesthetic techniques were topical anesthesia of the eye and infiltration anesthesia.

The central nervous system (CNS) comprises the brain and spinal cord. Neuraxial anesthesia refers to the placement of local anesthetic in or around the CNS. Spinal anesthesia is a neuraxial technique where local anesthetic is placed directly in the intrathecal (subarachnoid) space. The subarachnoid space houses sterile cerebrospinal fluid (CSF), the clear fluid that bathes the brain and spinal cord. An adult human has roughly 130 to 140 mL of CSF, which continually cycles throughout the day. Approximately 500 mL of CSF is produced daily.

Other neuraxial techniques include epidural and caudal anesthesia, each having its particular indications. Spinal anesthesia is only performed in the lumbar spine and is used for surgical procedures involving the lower abdomen, pelvis, and lower extremities.