Surgery ECG changes can first be observed when level of lignocaine is more than A 5 β 6 ug/ml B 10 β 12 ug/ml C 2 β 4 ug/ml D 1.2 ug/ml π‘ Explanation ECG changes can first be observed when level of lignocaine is more than β Correct Answer: A. 5 β 6 ug/ml