Noninvasive transcutaneous carbon dioxide monitoring

A new method for continuously and noninvasively monitoring carbon dioxide pressure in the skin tissue using an unheated transcutaneous carbon dioxide sensor is presented. The design, calibration, and principle of operation of the sensor are discussed. The transcutaneous PCO2 sensor was tested in vitro for response time, drift, linearity, and interfering anesthetic gases, all of which showed that the sensor is accurate, reliable, and immune to anesthetic gases. Clinical results using the unheated transcutaneous PCO2 sensor with neonatal patients are presented, verifying the clinical usefulness of the device for noninvasively monitoring trends in arterial PCO2.