Wireless Small Form Factor Wearable Sensing Patch: Beneficial Use of Electrode & Hydrogel Structure and Composition

Inventor: Srikant Pathak

There is a perceived need of small disposable wireless sensing devices in a small convenient form factor, which allows one to measure several vital parameters such as heart rate, respiration, activity, blood pressure, fluid retention, sleep disorder and numerous other physiological parameters which are useful and relevant to healthy population or a specific segment of patient population. Several such devices have been described in the literature. One key aspect of such devices is the patch form factor that could significantly affect the convenience and usability of such patches. The smaller is the patch the more convenient, usable and highly adaptable such a device becomes. One of the key features of such device is the ability to measure heart function using ECG signals. That can be accomplished in one, two or three electrode configuration- where the number of electrode, distance between the electrodes has a bearing on patch size and quality of ECG signals. Additional parameters that can be deduced from EKG or EKG signals are additional physiological signs such as heart rate, heart rate variation, respiration, fluid retention, sleep functions etc. Numerous health care organizations, physician association, technological and regulatory bodies have stated the underlying benefits of such devices for chronic disease and lifestyle management. However, even after a decade of technical attempts there are no widely available commercial solutions. One of the reasons for that is the difficulty in making such sensing patches cheap with high sensitivity and low signal to noise ratio.

Several concepts are described below which I believe could lead to useful directions. These are thought level concepts and no experiments have been performed. For compositional ideas experiments may be necessary to understand the real benefit they may provide. Based on the business direction one or more of these thoughts could be further developed and tested.

Problem Description: Improve signal to noise in a one lead wearable sensing patch device where the size of the patch is desirably very small.

Solution: Enhanced signal by capturing from a wider signal area by making one of the electrodes very large in two electrode single lead system. Electrode 1 (as shown in the illustration below) could be a conductive hydrogel. Electrode 2 could be realized by conductive hydrogel, conductive pressure sensitive adhesive or other suitable electrically conductive material. The position of Electrode could be in any concentric position from the center and need not be a continuous shape as shown in the illustration below.

(Figure 1)

Problem Description: Improve signal to noise in a small wearable sensing patch device where the size of the patch is desirably very small. Body contours, sexuality, topography, skin condition, presence of hair and ot...