Impedance-Enabled Catheter-Based Real-Time Hematocrit Sensor

Trauma is the leading cause of life years lost, with the majority of deaths resulting from hemorrhage. Commonly, physicians diagnose hemorrhage following a blood draw, delaying the clinical process; therefore, impedance analysis is integrated with a conventional peripheral intravenous catheter for real-time hematocrit sensing of hemorrhage in trauma patients. Variable hematocrit resulted in changes to the permittivity in the near field medium which is perceived in the electrode gap as capacitive change. Herein, we have experimentally demonstrated that spiral configured electrodes on a catheter can be implemented for real-time detection of hemorrhage by means of the changing hematocrit values.