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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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In epidural anaesthesia drug is injected
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The correct answer is  Epidural (extradural anaesthesia)Local anaesthetic is injected in epidural space, i.e., outside the dura mater with Tuohy&;s needleIn extradural space, LA acts on the nerve rootsIt is used in thoracic, lumbar and sacral (caudal) regions (in contrast to spinal anaesthesia which is given in lumbar region)Continuous analgesia is achieved by mixing the LA with an opioid, eg fentanylIt is mainly used to control postoperative pain (by continuous epidural anaesthesia)It can also b used for all surgeries which can be performed under spinal anaesthesia.(Refer: stoelting's pharmacology and physiology in anaesthetic practice, 5th edition, pg no.189)