Niranjan Khadka gave a presentation at the Annual Biomedical Engineering Day and Award Ceremony on May 01, 2015

BME Day, May 01, 2015, Department of Biomedical Engineering, CCNY

Wireless Pulse Oximeter (WiPOX): Its Clinical Implications and Challenges

The WiPOX provides a tool for surgeons to objectively and reliably measure tissue viability during surgery rather than rely solely on their subjective visual inspection. Tissue ischemia is a major cause of wound dehiscence or anastomotic leakage resulting in significant morbidity and mortality occuring at a rate of 15 to 25%. Although measurement of systemic blood oxygenation status by finger-tip pulse oximetery is a mandatory requirement for every anesthetized patient, there is no standadrad procedure for intra-operative measurement of internal tissue oxygenation following complex resections and reconstructions.

Based on clinical experience gained in our trials, we present here the design of a second generation WiPOX that includes a reticulated pressure-sensitive head serving two related functions. First, the often-restricted and sensitive environment in which the device is employed constrains both the angle of approach and visibility, necessitating a self- correcting reticulated swiveling head that acts to improve the contact angle between the sensor head and the tissue. Second, because the devices is hand-held, the pressure on the tissue (often a membrane) is determined by the operator; too little pressure produces poor signal to noise ratio (SNR) while too much pressure can occlude blood flow, also reducing SNR and possibly yielding erroneously low oxygenation measurements. To address this, our sensor head includes a novel mounting for multiple “balloon” style pressure sensors that provide feedback on tissue contact pressure and contact angle. The reticulated head and pressure sensor features function in tandem to improve tissue contact and ensure
reliable measurements.

VENUE: Department of Biomedical Engineering, CCNY, ST 402