Innervator NS 252, a new, constant current and programmable peripheral nerve stimulator.

A peripheral nerve stimulator should be able to deliver a constant current to provide supramaximal nerve stimulation even under conditions of increasing resistance. We tested a new programmable peripheral nerve stimulator, the Innervator NS 252. It was able to maintain a constant current of 80 mA up to a resistance of 3.9 kohm. The pulse appearance was correct and there were only small variations in stimulation time intervals. The different type of double burst stimulation and the lack of synchronization with the previously applied stimulus pattern may be regarded as slight disadvantages.