<prompt> Concentration of lignocaine used a 2b 4c 5d 10e 1bcdeabcdabceabde  <response>: Lignocaine is used in different concentrations for different regional blocks :- Surface topical anesthesia: 4, Nerve block : 1-2, Spinal anesthesia : 5, Epidural : 1-2, Biers block : 0.5 and infiltration block : 1-2. 