Hemodynamic response of small arteries to topical lignocaine

A unique, high-resolution pulsed ultrasound Doppler velocity meter (PUDVM) was used to measure blood velocity variables in 10 ensheathed rat femoral arteries, a common microsurgical research model. Measured variables included maximum spatial average velocities, temporal mean of the spatial average velocities, and velocity profiles across the lumens. From the measured variables, vessel lumen diameters and blood flow were estimated. With baseline data established, topical 1% lignocaine was applied to the artery. All measured and calculated variables increased to peak values at 3 min, as follows: maximum spatial average velocities, 27%, temporal mean of the spatial average velocities, 21%; diameter 6%; and calculated blood flow, 35%. This study suggests that the PUDVM instrumentation and technique can measure the blood velocity variables needed to derive blood flow estimates in the ensheathed rat femoral artery; and that the effects of topical pharmacologic agents, e.g., lignocaine, can be assessed.