Accelerated Recovery of DC Blocking Using Repolarization

Direct current (DC) can be applied to a nerve to generate a complete nerve block. However, using conventional platinum electrodes, reactions occur at the nerve interface causing damage to the nerve. The electrode can be separated from the nerve using a biocompatible, ionically conducting medium, which isolates the damaging reactions in a vessel away from the nerve. This electrode has previously been referred to as the Separated Interface Nerve Electrode (SINE). Recent experiments have shown that when a complete block is applied, for a prolonged period of time, there is a delay in the recovery of the response. For many applications it would be advantageous to have instantaneous recovery. To achieve this, the SINE electrode was used to provide a complete, instantaneous nerve block at the block threshold for 10 minutes and then the current was reversed for selected time periods to determine if instantaneous recovery could be achieved. Depending on the length of time of the repolarization, the amount of time for recovery can be reduced by as much as 50%.