Antithrombogenic pO2 sensor for continuous intravascular oxygen monitoring.

An antithrombogenic oxygen partial pressure sensor (Anthron pO2 sensor) was produced by coating a hydrophilic heparinized polymer (Anthron) on an etched epoxy composite ultramicroelectrode (microhole electrode). From in vitro tests, both the response time and stability were satisfactory under the conditions of a 20 microns thickness of Anthron coating and a depth up to 100 microns for the microhole. Additionally, results of in vitro tests without systemic heparinization demonstrated that a stable real time measurement of the intravascular oxygen partial pressure value was possible for a long period without thrombus formation or adhesion of blood components on the electrode surface of the Anthron pO2 sensor. Moreover, the measured data agreed with those from the blood gas analyser. Due to the thick thrombus formation on the electrode surface, the control (non-coated) sensor was unable to measure the intravascular oxygen partial pressure even for a short period of time.