| Spinal anaesthesia | |
|---|---|
 Backflow of cerebrospinal fluid through a 25 gauge spinal needle after puncture of the arachnoid mater during initiation of spinal anaesthesia | |
| MeSH | D000775 |
Spinal anaesthesia (or spinal anesthesia), also called spinal block, subarachnoid block, intradural block and intrathecal block,[1] is a form of neuraxial regional anaesthesia involving the injection of a local anaesthetic or opioid into the subarachnoid space, generally through a fine needle, usually 9 cm (3.5 in) long. It is a safe and effective form of anesthesia usually performed by anesthesiologists that can be used as an alternative to general anesthesia commonly in surgeries involving the lower extremities and surgeries below the umbilicus. The local anesthetic with or without an opioid injected into the cerebrospinal fluid provides locoregional anaesthesia: true anaesthesia, motor, sensory and autonomic (sympathetic) blockade. Administering analgesics (opioid, alpha2-adrenoreceptor agonist) in the cerebrospinal fluid without a local anaesthetic produces locoregional analgesia: markedly reduced pain sensation (incomplete analgesia), some autonomic blockade (parasympathetic plexi), but no sensory or motor block. Locoregional analgesia, due to mainly the absence of motor and sympathetic block may be preferred over locoregional anaesthesia in some postoperative care settings. The tip of the spinal needle has a point or small bevel. Recently, pencil point needles have been made available (Whitacre, Sprotte, Gertie Marx and others).[2]
- ^ Bronwen Jean Bryant; Kathleen Mary Knights (2011). Pharmacology for Health Professionals. Elsevier Australia. pp. 273–. ISBN 978-0-7295-3929-6.
- ^ Serpell, M. G.; Fettes, P. D. W.; Wildsmith, J. A. W. (1 November 2002). "Pencil point spinal needles and neurological damage". British Journal of Anaesthesia. 89 (5): 800–801. doi:10.1093/bja/89.5.800. PMID 12393791.