A Miniature Skin-Attached Hot Flash Recorder

We are developing an innovative miniature ambulatory hot flash recorder that is precise, accurate, reliable, affordable and aesthetically appropriate. It is a small disposable adhesive patch with two electrodes. A nondisposable, miniaturized, coated circuit board snaps onto the electrodes. The unit records the frequency, timing, and amplitude of hot flashes by measuring skin conductance, using no external wires or telemetry. The recorder contains a hot flash event marker that the subject triggers whenever she experiences a hot flash. Because hot flash skin conductance changes slowly, we measure every 10 s. We use pulsed waveforms to take the data, and sleep mode to conserve battery life. Since electrodes polarize if current always travels in a single direction, we use pulses in alternate directions. Data are downloaded directly from the patch to data acquisition software for computer display. The new recorder will be a valuable tool for researchers.