Transcutaneous Pressure Of Oxygen

CPC leads the industry in the standardization of TcpO2. TcpO2 is a surrogate measure of limb perfusion used in studies of angiogeneis in patients with severe peripheral arterial disease.

It has been reported that the measurement of TcpO₂ is difficult and has a high level of variability. This likely has curbed the use of the endpoint for clinical trials, but it is possible that a valuable measurement has been passed by for the wrong reasons. By utilizing a combination of training and oversight CPC can help control the consistency with which this endpoint is measured.

Factors affecting the variability of the TcpO2 measurement:

• Room temperature
• Electrode placement
• Consumption of caffeine within 30 minutes of the test
• Smoking within 30 minutes of the test
• The frequency of changing membranes and utilizing correct techniques when changing membranes
• Accepting final value without ensuring stability

These, and other factors effecting variability, can be controlled in a clinical research setting with thorough training and oversight.

CPC Interventions:

• Site Endpoint Evaluation Visit, which includes: 1) assessment of the sites’ equipment for appropriateness with the protocol, 2) assessment of the environment in which the test is administered, 3) evaluation of the techniques utilized by each staff member at the site that will administer these tests, 4) source document review to evaluate the site’s adherence to the protocol and CPC’s data collection guidelines, and 5) a detailed report to the site noting all issues at their site and specific recommendations for improving the consistency of the measurements
• A reference tool for sites to utilize during TcpO₂ monitoring
• Hands-on training to the site staff during an Investigator Meeting
• Development of source documents specific to TcpO₂ monitoring
• Weekly review at Endpoint Evaluation Committee meetings of issues identified during SEEVs; recommendations for corrective actions are forthcoming from this meeting
• Receiving phone calls or other inquiries from sites about data collection methods

CPC offers quality assurance of TcpO2 monitoring as described as well as quality assurance for other endpoints utilized in clinical trials. For more information on these services, please Contact Us or call 303.860.9900.