Noninvasive Technique to Monitor the Pressure under a Cast: A Mobile Application-Friendly Bluetooth Pressure Sensor

Area of Science:

• Biomedical Engineering
• Medical Device Technology
• Wearable Sensors

Background:

• Casts are essential for immobilizing fractured limbs, but can cause complications due to pressure.
• Monitoring skin-cast contact surface pressure (SCCSP) is crucial for preventing adverse events like compartment syndrome.
• Current methods for assessing cast pressure are often indirect or invasive.

Purpose of the Study:

• To design and validate a novel sensor system for real-time SCCSP monitoring.
• To develop a mobile application for user-friendly data display and alerts.
• To assess the system's ability to detect pressure changes indicative of limb swelling.

Main Methods:

• An experimental setup using an infant sphygmomanometer cuff and a Bluetooth-enabled pressure sensor was employed.
• The sensor was placed on the forearm of 10 volunteers before applying a synthetic short arm plaster cast.
• Measured SCCSP data was transmitted wirelessly to a mobile application for processing and conversion to mmHg.

Main Results:

• The developed sensor system accurately measured SCCSP, with values ranging from 0 to 75 mmHg.
• A high correlation coefficient (0.993) was observed between mean pressure values, indicating high reliability.
• A significant relationship was found between intracompartmental pressure (ICP) and SCCSP, validating the sensor's clinical relevance.

Conclusions:

• The Bluetooth pressure sensor system enables effective monitoring of SCCSP under casts.
• The system can detect limb swelling by identifying increased pressure.
• Real-time alerts via a mobile application enhance patient safety and care.