Spinal anaesthesia (or spinal anesthesia), also called spinal analgesia or sub-arachnoid block (SAB), is a form of regional anaesthesia involving injection of a local anaesthetic into the subarachnoid space, generally through a fine needle, usually 9 cm long (3.5 inches). For extremely obese patients, some anaesthesiologists prefer spinal needles which are 12.7 cm long (5 inches). The tip of the spinal needle has a point or small bevel. Recently, pencil point needles have been made available (Whitacre, Sprotte, Gertie Marx & others).
Read more about Spinal Anaesthesia: Difference From Epidural Anesthesia, Injected Substances, Mechanism, Limitations, History, Worldwide Usage, Indications, Contraindications, Operations, Complications