Effects of lidocaine concentration on distal capillary blood flow in a rabbit ear model

The laser pulse doppler provides a noninvasive, reproducible method to measure the flux in distal capillary blood flow in a rabbit ear model. The distal capillary blood flow responds proportionally to changes in periarterial lidocaine concentration. The response is biphasic. Flow initially decreased from the baseline in all lidocaine concentrations between 0.5% and 10.0%. Proportional increases in distal blood flow above baseline are noted as the buffered lidocaine concentrations increase from 1.0% to 10.0%. Lidocaine concentration of 0.5% dose not increase distal blood flow above baseline.