In epidural anaesthesia drug is injected -
Ans. is 'a' i.e., Outside the dura Epidural (extradural anaesthesia)o Local anaesthetic is injected in epidural space, i.e. outside the duramater with Tuohy's needle.o In extradural space LA acts on the nerve roots.o It is used in thoracic, lumbar and sacral (caudal) regions (in contrast to spinal anaesthesia which is given in lumbar region).o Continuous analgesia is achieved by mixing the LA with an opioid, eg fentanyl.o It is mainly used to control post operative pain (by continuous epidural anaesthesia).o It can also be used for all surgeries which can be performed under spinal anaesthesia.Comparison between spinal and Epidural anaesthesiaSpinal (intradural) anaesthesiaEpidural (extradural) anaesthesiao Faster onset of actiono Slower onset of actiono More reliableo Less reliableo Easier (loss of resistance and presence of CSF from needle can confirm the space)o Difficulto Has limited duration of action - prolonged surgery can not be performedo Duration can be prolonged by repeatedly injecting LA by an epidural catheter.o Used only for surgery of lower part of body - lower abdomen, lower limbs, gynaecological, and obstetrical surgeries, e.g. hystrectomy, caesarean section.o Can be used for upper abdominal, thorasic & neck surgery as well in addition to surgeries performed by spinal anaesthesia.o Post dural puncture headache is commono PDPH is unlikely because dura is not pierced - so, there is no CSF leakage
Outside the dura
Inside the duramater
Inside arachnoidmater
Inside piamater
Spinal, Epidural, & Caudal Blocks