Hydration sensor development for use on infants in underserved areas

[摘要] ENGLISH ABSTRACT: To treat dehydration in infants a good measure of dehydration level is required. Clinical hydration scales are the standard for assessing hydration upon first examination. These scales rely on the training of the physician and do not perform well when applied in underserved settings where the vast majority of infant mortalities due to dehydration occur. This study proposes three sensors for the non-invasive assessment of dehydration. All three sensors measure proven indicators of hydration (capillary refill time, skin recoil time and skin temperature difference) and the aim is to eventually allow untrained personnel to reliably measure these hydration markers with greater inter-rater reliability. A proof of concept prototype of each sensor was fabricated and the sensors were tested in two separate studies. The skin recoil time and temperature profile sensors seemed to perform fairly well when tested on infants, however, because of the small sample size of the infant study, no realconclusions could be drawn about the link between the measured markers and hydration state. A systematic method of finding a model, that combines the best predictors, was presented, however the model performed only marginally better than the best individual marker, most likely due to wanting orthogonality between the predictors. Skin recoil time, which is the marker that performed best in the clinical study, achieved a sensitivity and specificity of 0.8 and 0.84 respectively for detecting 5% dehydration, which is better than the expected performance of any single commonly accepted hydration marker. Interestingly, this combination of sensitivity and specificity was achieved at a binary threshold of 0.08 seconds. As mentioned previously, the data does not make it possible to draw solid conclusions about the performance of the device, however the presented evidence makes a strong case for continued research into the presented methods.

[发布机构] Stellenbosch University