Final answer:
Spinal anesthesia, also known as spinal block, is a type of regional anesthesia commonly used for surgeries from the waist down. It involves injecting a local anesthetic into the cerebrospinal fluid to block nerve signals and provide numbness in the lower body.
Step-by-step explanation:
Spinal anesthesia, also known as spinal block, is a type of regional anesthesia that involves injecting a local anesthetic into the cerebrospinal fluid surrounding the spinal cord. It is commonly used for surgical procedures from the waist down, such as lower abdominal, pelvic, or lower limb surgeries.
During spinal anesthesia, a small needle is inserted into the subarachnoid space of the spinal canal, and the local anesthetic is injected. This blocks the transmission of nerve signals, resulting in loss of sensation and muscle weakness in the lower body. Advantages of spinal anesthesia include rapid onset, profound anesthesia, and minimal systemic side effects. However, it may be associated with complications such as low blood pressure, headache, or backache.