About lidocaine all are true, except: (A) Dose need to altered in renal failure, (B) Loading dose before infusion, (C) It is little effected by heat & pH, (D) Prolongs refractory period
Answer is A. Local anaesthetics are poorly water-soluble and this limits their renal excretion to less than 5%. For treating ventricular arrhythmias initial loading dose is to be followed by infusion. The amides are so stable that they are not effected even by autoclaving. Effective refractory period (of cardiac tissue) is prolonged by local anaesthetics.