TRANSCUTANEOUS OXYGEN-TENSION MEASUREMENT IN PATIENTS WITH CHRONIC ARTERIAL OBSTRUCTIVE DISEASE - RELIABILITY AND LONG-TERM VARIABILITY OF THE METHOD

Although transcutaneous oxygen tension (TcpO2) measurement may be usef ul for assessing changes in regional perfusion induced over time by dr ug or surgical treatment in patients with chronic arterial obstructive disease (CAOD), the reliability of the method over a long-term period is not know. To approach this problem, the authors evaluated retrospe ctively the behavior of TcpO2 measurement over time in patients with C AOD. To eliminate confounding influences due to the concomitant vascul ar disease at the limb level, data analysis was performed on TcpO2 mea sured at the right infraclavicular position. The median length of foll ow-up ranged from twenty days in 34 patients to 832 days in 3 patients (n = 2 and n = 1 0 individual sequential replications respectively). Initial and final TcpO2 Values did not differ significantly even at th e longest follow-up term, which indicates that the parameter is consta nt over time. The intrapatient variation coefficient of TcPO2 (calcula ted over at least three individual replications) ranged between an ave rage of 11% to 16.2%. The corresponding interpatient variation fluctua ted between 15.5% and 33.4%, a variability explained to some extent by sex-related influences, but, at least in the range of this sample, no t by age, arterial oxygen levels, or disease status. Thus TcPO2 levels per se are stable, implying that TcPO2 measurement has the potential to record consistent changes caused by specific therapeutic interventi ons or the clinical evolution of patients with CAOD. However, the intr apatient and interpatient variability of the method has to be taken in to account when TcpO2 is used for the follow-up and the physiopatholog ic study of patients with CAOD.