Semi-Implantable Antenna Integrated into a Medical Needle

Peripheral venous/arterial catheters are among the most used devices in hospitals to inoculate fluids or to perform medical tests. These devices are invasive and not immune to risks. Namely, the insertion of a catheter can frequently lead to Catheter-Related Bloodstream Infection. The diagnosis is currently based on qualitative clinical observation of the insertion site and, rarely, by temperature monitoring with expensive infrared thermography. The cannula equipped with temperature-sensing capability and wireless communication connectivity could enable periodic remote monitoring of the insertion site at lower costs. This paper describes a method to equip the polymeric cannula with an antenna and a battery-less RFID IC, that is provided with an integrated temperature sensor. The resulting Smart Cannula is fully biocompatible and leaves unperturbed the lumen of the blood vessel. Numerical simulations and preliminary tests demonstrated a reliable communication link with a hand-held, or fixed reader at the bedside, up to 35− 50 cm.