ELECTRICAL currents have been used to produce unresponsiveness to stimuli for many years. In 19024 Leduc employed unidirectional pulses for general anesthesia in dogs and rabbits using pulses of one millisecond duration at frequencies as high as 200/sec. More recently Anan'ev1 has modified the Leduc technique by adding a direct current bias. Rectangular potentials derived from a low impedance generator at 100/sec were raised above the zero baseline by a direct component and applied across the head. Satisfactory anesthesia was obtained, and undesirable effects such as apnea, limb movements, or convulsions were not observed. Similar experiments were carried out by Smith and Cullen6 with approximately the same results. Other investigators have used sinusoidal currents. Although Knutson3 and associates were able to produce anesthesia in dogs with 700 cycle sinewaves and no supplementary agents, they observed motor activity, hypertension, and increased l-epinephrine and l-norepinephrine blood levels.
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