text: The term<unk>  is often short for<unk>  anesthesia, a form of regional anesthesia involving injection of drugs through a catheter placed into the<unk>  space. The<unk>  space (or extradural space or peridural space) is the space inside the spinal canal but outside the membrane called the dura mater (sometimes called the "dura"). In contact with the inner surface of the dura is another membrane called the arachnoid mater ("arachnoid"). The arachnoid encompasses the cerebrospinal fluid that surrounds the spinal cord.<unk>  analgesia (pain relief) is a type of Regional Anesthesia which is commonly used to ease the pain of labor and childbirth but can also be used to provide anesthesia for other types of surgeries. A Spanish surgeon named Fidel Pagés Miravé reported the first single-shot thoracolumbar<unk>  anesthesia in 1921. After a decade, the Italian surgeon Achille M. Dogliotti described a reproducible loss-of-resistance technique to identify the<unk>  space.<unk>  is a technique for perioperative pain management with different applications in anesthesiology and it can be a single shot or a continuous infusion for long term pain relief.<unk>  is excellent analgesic, it decreases the side effect of other anesthetics and analgesics and reducing their side effects. Low blood pressure, fever, nausea, difficulty urinating are complications of<unk>  anesthesia. An<unk>  is a way of anesthetic which is used for pain relief during labor, it stops pain signals traveling from the spine to the brain. During labor, anesthesiologists injecting a small amount of anesthetic into the<unk>  space of the spine. The<unk>  space is filled with fluid and surrounds the spinal cord. Nerves that carry pain signals from the body to the brain (spinal nerves) connect to the spinal cord in certain places. The anesthetic numbs the spinal nerves, blocking the pain signals.
  Spinal anesthesia is a technique whereby a local anesthetic drug is injected into the cerebrospinal fluid. This technique has some similarity to<unk>  anesthesia, and the two techniques may be easily confused with each other.
option_0: Epidural
option_1: Reposal
option_2: Orbit 
option_3: Operon
option_4: Subdural space
option_5: Cervical plexus
option_6: Morrhuate
option_7: Ainhum