Concentration of lignocaine used – a) 2%b) 4%c) 5%d) 10%e) 1%

Lignocaine is used in different concentrations for different regional blocks :- Surface (topical) anesthesia: 4%, Nerve block : 1-2%, Spinal anesthesia : 5%, Epidural : 1-2%, Bier's block : 0.5% and infiltration block : 1-2%.