DISPOSITION OF LIGNOCAINE FOR INTRAVENOUS REGIONAL ANESTHESIA DURING DAY-CASE SURGERY

Lignocaine is a suitable and safe agent for intravenous regional anaes thesia (IVRA) with rapid onset of good surgical anaesthesia. The onset time of the local anaesthetic action of lignocaine was 11.2+/-5.1 min . Satisfactory surgical conditions, evidenced by good sensory blockade were achieved within 20 min, and no additional analgesics were requir ed. There was no trend towards a fixed sequence, radial, median and ul nar in the development of sensory blockade. No patient exhibited objec tive symptoms of toxicity, either local or systemic, after release of the tourniquet, nor were there any subjective complaints. No changes i n blood pressure, heart rate or oxygen saturation were observed at any time during the procedure, or after deflation of the tourniquet. Afte r releasing the tourniquet lignocaine is rapidly and biexponentially e liminated, with a t(1/2a) of 4.3+/-2.1 min and a t(1/2 beta) of 79.1+/ -31.2 min. Total body clearance was 0.86+/-0.39L min(-1). Eight patien ts showed rapid release of lignocaine from the exsanguinated area. in two patients the systemic plasma concentration of lignocaine increased more slowly than in the remaining eight. This can be explained by a g reater degree of lignocaine absorbtion in the tissues of the arm. Phar macokinetic constants after rapid and slow absorption were calculated.