Peripheral nerve responses during ischemia in the evaluation of diabetic neuropathy.

The stability of sensory conduction and evoked potentials during ischemia has been used in the evaluation of diabetic neuropathy and diabetic control (Hgb A1C). Six newly diagnosed juvenile diabetics were studied at diagnosis and 3 to 12 months later. In three patients in good control, ischemic "resistance" became normal. In three patients in poor control, resistance remained increased; two of these three experienced a 10%-20% slowing in conduction velocity. Similar relationships between control and ischemic resistance are found in long-term diabetics. These data suggest that abnormal ischemic resistance may herald the onset of an electrical and clinical neuropathic state.