Point-of-Care Wearable Pressure and Temperature Sensor System for Therapeutic Compression Garments and Venous Leg Ulcers

Venous stasis ulcers (VSUs) are the most common ulcerative wounds in the elderly affecting 1.7% of all individuals older than 65. More than 650,000 elderly individuals suffer from VLUs, which cost nearly $10,000 to treat. The overall cost to the medical system is $3 billion USDs yearly. Although there has been significant advances in the science of wound care including the development of novel bioengineer wound products, there remains significant uncertainty over the judicious use of these expensive treatments. Given the inherent differences of aged skin, even less is known in regards to optimal strategies for treating VLUs in the elderly population. In contrast, therapeutic compression garments are widely accepted as the standard of care to speed VSU healing for all age groups. Numerous well-designed, high-quality clinical studies have demonstrated the clinical value, safety, and cost-effectiveness of compression garments when used consistently and with sufficient pressure delivery (>35 mmHg). Currently, there is a lack of clinical tools able to provide clinicians and patients with important diagnostic information regarding the pressure being delivered by compression stockings that is sensitive to limb volume changes over time. Existing pressure sensors are bulky, expensive, and inaccurate. They are not conducive to wearable use given a lack of wireless communication. This has limited these devices to only select research applications. Thus, there is a critical clinical need for a wearable diagnostic tool that is able to provide accurate, and repeatable measurements of pressure and temperature that poses no risk to vulnerable lower extremities. Pressure measurements can be used by both trained clinical staff and the patient to adjust compression garments to ensure adequate pressure delivery. Temperature is useful to ensure patient adherence but also serve as an independent marker of skin inflammation and wound risk. The proposed work addresses this need with a sensor technology breakthrough. The ultra-thin device incorporates an embedded pressure and temperature sensor within a soft, flexible silicone based that is thin, and highly comfortable to wear. There is no rigid surfaces, thus eliminating the risk of skin injury to highly vulnerable lower limbs. By using near field communication with existing smartphones, the technology is batteryless, and wireless enabling a favorable cost profile and disposable use. Activities in Phase I will establish the accuracy of the sensors through systematic testing procedure against gold-standard tools for low-pressure ranges (0-100 mmHg). In addition, the ability of the sensor to accurately report pressure on substrates of varying hardness will also be demonstrated. Pilot testing on elderly individuals ages 65 years or older will ensure tolerability and safety of the device, as well as user adherence