Spinal and epidural
A spinal is a single injection into cerebrospinal fluid below the end of the cord, giving a dense, fast, finite block from a tiny dose. An epidural is a catheter in the epidural space, giving a slower, segmental, titratable and extendable block from a much larger dose. The difference in dose is why a dose meant for an epidural given intrathecally is a total spinal.
Peripheral blocks and ultrasound
Ultrasound turned regional anaesthesia from a landmark technique into an anatomical one. See the nerve, see the needle in plane, see the local spread around the target, and stop if the patient reports pain on injection or if injection pressure is high.
The contraindications that matter
Patient refusal, infection at the site, and uncorrected coagulopathy or anticoagulation within the timed window. Neuraxial block in an anticoagulated patient risks a spinal haematoma, which presents as unexpected weakness or back pain and needs imaging and decompression within hours to be reversible.
Local anaesthetic systemic toxicity
Perioral tingling, metallic taste and tinnitus, then agitation and seizures, then cardiac arrhythmia and arrest. Stop injecting, call for help, manage the airway, treat seizures, and give lipid emulsion. Bupivacaine arrest can require prolonged resuscitation, and prolonged is the operative word.
Watch it done
Spinal anesthesia explained, part 1: crash course with Dr Hadzic
The regional anaesthesia school's teaching on the spinal: landmarks, needle, the level, the block.
Source: NYSORA · Watch on YouTubeWatch for
- Tuffier's line and the interspace
- Free flow of CSF before injecting
- Baricity and the level the block settles at