Epidural Anaesthesia :
Epidural space has Negative pressure.
Lignocaine : 1-2%
Bupivacaine : 0.25 - 0.5%
Drug required is high - 15 - 20ml (Penetrates intervertebral foramina into CSF)
So there are high chances of Total Spinal anaesthesia and LA toxicity.
Also epidural space has large number of veins - Venous plexus of Batson
Needle : Tuohy Needle , Crowford Needle
How to know if we are in the Epidural space ?
1. Loss of resistence (On piercing Ligamentum flavum)
2. Hanging drop technique. ( Gutierrez's sign )
3. Rapid injection in the space causes increase in rate and depth of respiration. ( Duran's Sign )
4. Absence of knee jerk after epidural block. (Westphal sign )
Advantages over Spinal Anaesthesia:
- Less Hypotension
- No headache
- Level block can be done
- Any duration can be performed.
- Patchy block (therefore give fentanyl)
- Chances of Unsuccessful block
- High chance of total spinal
- Effect starts in 15-20mins [ therefore use combine Spinal and Epidural (CSE) ]
Caudal Block = Sacral epidural block : LSCS NOT Possible with this.
Drug injected - Xylocaine 2mg/kg , in Sacral hiatus.
Most commonly used in children
Good for Perineal surgeries and infra-umblical pain relief in children.